CE Project: CE Bot

This is one of the few ongoing Crazy Engineers projects.

Project Goal (General):

Design and develop a medium sized robot with the given specifications.

Project Objectives (Listed in Priority + Timewise):

1. Discuss the specifications of the bot, physical size and its use. What is the bot for? What functions will it perform? The Why and What. TIME: 1 week.

2. Draft a rough model. List what all modules would you like to see on the bot? Processor? Motors? Motor drive? Power source? Webcam? Ethernet? Parallel com, Serial com, USB com, etc TIME: 1 week

3. Put the modules together, each module must have specific Input Output relation with the main on board processor. TIME 2 weeks.


We will first finish with these steps and then follow through. Anyone who has an idea can take part but remember the format!!

Give your idea, then support it with good reasoning, then point to any sites and/or documentations to further support it. At the end of the 2nd objective, I would like to see the serious contributers make a powerpoint presentation (you can make it on Google Documents) and upload it here or on google docs.

I will add more when I see enthusiastic response to this project.

xhx, hope you don't mind me adding some stuff here. -ash

ANNOUNCEMENT: Celab.tk is no longer accessible. Please go directly to:

#-Link-Snipped-#

for the Project Website, thank you.

Current contributors: xheavenlyx (project leader), ash, bayazidahmed, gohm, sanih, raj87verma88, joe3204

Replies

  • xheavenlyx
    xheavenlyx
    So this is our first step:

    Project Objectives (Listed in Priority + Timewise):

    1. Discuss the specifications of the bot, physical size and its use. What is the bot for? What functions will it perform? The Why and What. TIME: 1 week.

    Must finish in 1 week. Anyone interested can add for now.
  • Ashraf HZ
    Ashraf HZ
    Great work, man. However, maybe we should extend the deadline a little ๐Ÿ˜‰ 1 week is a little to soon given the relatively low activity here. How about 2?

    I've got number of different ideas. But since we MIGHT have some interest with the Google Lunar X challenge, here's my initial draft.

    1.
    The bot will be a rover-like vehicle, able to traverse over rough surfaces to get from point A to B. It'll be able to detect objects with the use of image-processing and other proximity sensors. Cameras will be used to record data and wirelessly transmit data to a computer.

    On the computer, the data can be processed to create some kinda terrain map. 3D perhaps?

    The bot itself can be autonomous or remote control. If autonomous, the bot detects some beacon at point B and goes to it while avoiding obstacles (obstructions, holes, traps?) and taking data.

    The size is relatively small, maybe the footprint would not be larger than a standard magazine.

    So, with that, we have all sorts of engineering disciplines involved. I'll update it once I get more ideas.
  • xheavenlyx
    xheavenlyx
    That is an excellent idea, specially about it transferring the video data to an off board computer for it to be processed into a 3D terrain map.

    I was thinking, we must not concentrate on the moon rover. This other team which will be joining soon will be bringing their own design and they just want us to help. Anyway, moon rover is no easy task, we can talk as much as we like but the reality is very different. I am pissed off too after realizing this...like take off, landing and survival in Xtreme temp -173`C to +100`C! Making a rover is a cake walk compared to the other tasks.

    Anyway, we can make a small rover which can move into small places and need not have a plain ground, it can also "traverse" into a hole vertically. Why this? Firefighters and rescue teams can use it many cases. In India itself we have many incidents of ppl falling into holes, or building collapse, or floods etc.


    I agree with the size too. Has to be small.

    Proposed Ideas:

    1. Time for each task is 2 weeks now.
    2. Possible components under Sensors: Camera, Wireless transmitter (Ethernet, not bluetooth- need range), Temporary storage.

    3. What do you think about most of the process being taken care of an offboard computer? Should it be manual or auto or semi-auto controll?
  • bayazidahmed
    bayazidahmed
    Yup you are right. Moon rover is not an easy job but not impossible.

    It would be a hard time for me to decide what to do with this robot, but if others have a definite plan I can help with tasks 2 and 3.

    Compnents:
    1. Camera: Necessary for self navigation of the robot
    2. Serial/Parallel or USB port - for connecting to the robot
    3. Wireless: Bluetooth has a max range of 100m (Class I) and uses less power (the biggest advantage). Other possible option is WI-Fi.
    4. Processor: A good microcontroller will take car of all the jobs. I could be a very good help while programming this thing.
    5. Temporary Storage: It oculd be anything, from a small memory card (SD/MMC) to a complete hard disk. Nowadays storage is pretty cheap, so we dont have to worry much about the cost factor. When connected vai the ports or wireless, we should be able to acces the temporary data stored here like log files, raw data that is being captured thorught its mic or camera, etc..
    6. Arms: Ateast two arms so that it can pick up things or move objects from its way.
    ....
    .....
    ......
    and let the list grow..


    In btw, why the heck there is very little activity in CE?
  • Ashraf HZ
    Ashraf HZ
    Great contribution bro!

    Yeah, we are not really working on an actual Lunar Bot that will be sent to the moon, but a normal rover that does similar functions (ie navigate over a rough surface, collect data, transmit data etc). xheavenlyx, thats a good point about using it for rescue purposes. If we plan to go vertical, we might look at the use of legs instead of wheels (like a spider). Reminds me of the topic we discussed here:
    #-Link-Snipped-#

    Low power consumption
    We'll try keeping most of the processing offline, so that the bot does not consume much power. That would also include using a wireless transmitter with a good range to power ratio. Low power = small battery supply = reduced weight and size. But remember guys, the transmission channel may not always be perfect! You must consider the fact there is interference, and that the bot is not stationary.

    If we plan to use microcontroller, we must design the circuitry as efficient as possible. Now we need a balance between cost/efficiency like proper voltage regulators, etc.

    For storage, we can use the a flash storage like bayazid suggested. It'll probably act to store robot instructions as well as a buffer for data (since we are transmitting it off later). However, if you want to change the bot's role to collect all data first, then we may need a bigger storage solution.

    We need a rough sketch of the bot. Very hard to visualize with just words. Later, mechanical/mechatronic CEans can draft them on CAD software ๐Ÿ˜€

    In btw, why the heck there is very little activity in CE?
    We need a critical mass of active CEans, I suppose. However, Big K is putting a lot of effort to get more members and encourage participation.. look out for that!
  • xheavenlyx
    xheavenlyx
    Good Ideas! ๐Ÿ˜€ So now we have these components as @bayazid and @ash have pointed:

    Compnents:
    1. Camera: We can see later what kind of a camera, and how it will be connected.

    2. Serial/Parallel or USB port: We can keep all if he make one concideration, see below.

    3. Wireless: Bluetooth or Wi-Fi. But since we need more range we can have Class 1 BT or a Wi-Fi, that will depend on the processor.

    4. Processor: IMPORTANT CHANGE. See below.

    5. Temporary Storage: A hard drive can be used, as a temp storage and as a buffer depending on the time and need of the data! It can also be used as a log when something goes wrong in a rescue operation.

    6. Arms: Very good suggestion! We can have one or two. Lets see how the design proceeds.
    4. Processor: Now this is an important factor. I was thinking, why not use an old laptop, which has all the important things! Parallel port x1, Serial x1, USB x2, A hard drive, an expansion slot for wireless or bluetooth (swappable) and a custom linux backed firmware for operations. All programming can be done in C or Python. Can have more AI then what a normal microcontroller can support. We can remove the screen for power saving or keep it for status of machine, testing etc etc. I have an old acer with me and never found a use for it ๐Ÿ˜€

    7. Motion mechanism: How about something of the likes of this, but not the same:

    #-Link-Snipped-#
    #-Link-Snipped-#

    Ash, programming the legs can take up a lot of processing power! Since even in a vertical drop, a legged robot cannot be more productive then a wheeled, because anyway we will be hoisting it down with a rope! If we design a legged, then we have to concentrate on the mechanism and programming. We can have another project in the future with a snake like moving ability or legged, even I want to do something different than wheels, but for this one we can have a tank type drive. What do you think?

    And as for the outer design and chassis, we will do that after we finalize the components ๐Ÿ˜€
  • bayazidahmed
    bayazidahmed
    Hi CEans! Call me ahmed.

    Coming straight to the point.
    Laptop?? Are you sure? Do you know how much your acer laptop weighs?
    Even if we keep the issue of weight aside, there are some other problems with using a laptop.
    1. The major problem is with ports: Your Laptop has only one parallel port. Parallel ports are a great help in designing things. For instance, take the case of wheels. For wheels we will be using stepper motors, stepper motors require 4 pulses. So two stepper motors for the two sides, that amounts upto 8 pulses or 8 pins from the parallel port. Now, the parallel port on the laptop has only 8 i/p/o/p pins! How will we configure other things like the arm and other components that will be attached to it? Camera can go to the USB. I think we need atleast 32 bits to program this beast.
    2. Weight
    3. Size: Its quite bulky
    4. Customization: another biggest disadvantage, you cant customize it to fit exactly your needs. All ou can play with is programming, and that take half the fun out.
    .....
    ......

    Having said all this, I am not completely disagreeing with the suggestion of xheavenlyx using a laptop. There are many advantages to it as well.
    1. You have everything assembled! All you have to take care of it is programming.
    2. Programming is much easier. With a microcontroller you wil have to go for ASM though there are some compilers available fro microcontrolles hat convert your C program to ASM.
    3. Communication part becomes easier with the LAN/bluetooth/Wi-Fi of the laptop. With the microcontroller we will have to go for a serial port (I call this an advantage, but I am in favour of a serial port, it looks professional ๐Ÿ˜Ž)
    4. Crazy: We are turning a laptop into a robot, and this falls into the category of crazyness!
    .....
    ......
  • Ashraf HZ
    Ashraf HZ
    I'm down with fever, so I can't think of any new ideas to contribute ๐Ÿ˜” laptop sounds good, but remember we are doing most of the data processing offboard.

    In terms of weight, we can just use the motherboard.. no need for the laptop chasis. You'll just have one big ass PIC board then. What else.. um, as ahmed said about the parallel port, I guess we need to multiplex it ๐Ÿ˜€ We can also use other I/Os; the mic input/sound output can be used as a ultrasonic detector, with modifications of course. We can safely rid the screen entirely, as long as you have a VGA output!

    I like the tank track idea. Looks cooler ๐Ÿ˜› We can still use a microcontroller, I guess. Connect it to a serial or USB, hehe.

    However, im still an advocate of using low power. What processor does the Acer laptop have, xhx?
  • xheavenlyx
    xheavenlyx
    Wow! Both of you have raised amazing points!!

    Ahmed, thats a good point. Here are a few things I would like to clear:

    1. Yes, ports can be a problem (Refresh: 1 PP, 1 Serial rs232, 2 USB), but I wanted to include something very vital in the project. Similar to the lines of what ash pointed out. I will talk about it in the end.

    2. You are right about the weight, but we can try our best to strip it down. It uses a P1 processor. 128 MB RAM. Still have to see power consumption. As ash said, we can keep the VGA-outpt and remove the screen. I also think, for some field jobs we need good traction, if its okok light then it can slip off surfaces and be a bit ... flimsy. Dont know, lets see. From robot competetions I have seen on TV. A 200 lb (about 90+kg) can run good on affordable batteries.

    3. Above ๐Ÿ˜€

    4. Customization: Another important factor. But what does the laptop replace? Only the mC. Still we have the motors, sensors and the power management to handle. Well, we have the most flexibility with a powerful processor with "INFINITE" inputs ๐Ÿ˜ This is the fun part, the processor and the inputs! See next post on Processor and Input/Output.
  • xheavenlyx
    xheavenlyx
    CE Project: CE Bot: Processor

    Firstly here is the links for the ACER Extensa 500 laptop.

    #-Link-Snipped-#
    • The Processor is Intel Pentiumร‚ยฎ processor with MMX technology.
    • 166, 200, 233, 266 MHz
    • MMX technology provides 57 new instruction sets to improve processor performance in traditional digital signal processor [DSP] applications, including the graphics, audio and voice processing capabilities now emerging as value-added features in high-performance embedded products. MMX technology can potentially eliminate the requirement for DSP chips in embedded applications such as video kiosks, telecommunications devices and POS terminals.
    Why I support using this processor instead of a PIC? Well, we have huge potential to expand the on-board functionality! I mean, we are doing so many tasks, in a controlled manner, and on the way helping in the manual control even if its not fully automated! Like, motor drives, 1 (or 2) arm(s), camera, IR, sonar (ultrasound), temperature, and optimizing the power usage.

    Ok, now the problems of I/O.

    Two solutions exist, in my head, you can add in too! ๐Ÿ˜€

    1. Using multiplexers. This can get a bit complicated (havent thought on this one) but is possible to get 32 or 64 bits from 8 bit I/O. One disadvantage is that, the mux are non-intelligent devices. How? :

    2. Using simple PIC mCs connected to the PP and Serial: Think of a multinational company. We have the board members (main processor), the managing directors of each division (PIC's connected to the Proc.), the workers (modules, sensors connected to PIC's). This way we can have more ADC's (Analog to Digital Converters), more Inputs and more outputs. PIC's have interupts to stop a processes in emergencies. They can either do their own calculations and take an action or simply report to the processor.

    Software wise we can have C functions specifically written to program the PIC's whenever needed through the Serial port!

    Now the tough part is sitting down and designing the protocol and methods. I am willing to help on that.

    What do you guys think? Of this looooong and tiring post ๐Ÿ˜€

    ***
    *EDIT*
    ***

    Oh, yea, and another method is using a network of PIC's connected to each other and forming an intelligent network. Each one can take own modules to control, using their own head, or talking to each other to know the status and take actions.
  • bayazidahmed
    bayazidahmed
    Multiplexers is not an option

    Connecting teo PICs, one to PP and one to SP will solve the problem but make the complete thing quite bulky. One Pic can control the basic functions of the robot like wheels, arms, cameras, etc... and the other can be used to mointor the various sensors and for any additional functions apart from the basic ones.

    A network of PICs is a very good idea, it will be a bit complicated. Lets not concentrate on this for the time being and keep this feature for version 2.0.
  • gohm
    gohm
    I was thinking treads for locomotion as well. Oversized so it can still run if it gets flipped over.

    What about a gas detector? Can detect the threat of carbon monoxide, natural gas leaks, etc. that could be a risk to people entering area afterwards (scientists, rescue workers). The vehicle itself would need to be spark proof.

    temp. probe or camera using IR.

    A bulldozer type front blade to push objects out of the way to the side? That way you only need one grab arm. Arms would be more likely to break in a fall or tight places.

    Do you want a speaker/mic/sound card for basic speech communication?

    What degree of water resistance would this require? none, resistant or proof? I would vote for resistant.
  • bayazidahmed
    bayazidahmed
    there must be some hooks as well, fro it to carr oxygen pipe, etc...

    yes, there should be a speaker and a mic on it.
  • xheavenlyx
    xheavenlyx
    Oh my god, I just typed a huge reply and it got erased on a refresh!

    i will go now, look for a gun and load it and then point it in my mouth and shoot................SH!!!!T
  • xheavenlyx
    xheavenlyx
    all I can say is Gohm, good ideas, great!@!!!

    And ahmed, we either use Processor plus 2 PIC's on PP or Serial OR a PIC network. Nothing else will work in this highly complicated project. Weight is not an issue. How can 2 PIC's make it bulky?

    Power is important, 266 MHz is a LOT better than a PIC32's 40 or 80 MHz for controlling:
    (Note: ive put in comments for the ideas by Gohm and ahmed too)
    We have to handle the following AND send it wirelessly.


    1. Motors
    2. IR cam/normal cam (Video of my IR cam I made sometime ago: - YouTube)
    3. Speakers : Use laptops or make independent FM trans/reciv.
    4. Temperature
    5. One arm (DOF-Degree of freedom unknown at present)
    6. Gas detector is not cheap but good idea if we can afford em:
    Combustible gas detctr.: <$200
    Multiple:$1000+
    #-Link-Snipped-#

    7. waterproofing: Good.
    8. Compressed Oxygen tank small for supply:
    Theory ๐Ÿ˜€ : #-Link-Snipped-#
    Buy it? :#-Link-Snipped-#

    Sorry, my original reply got deleted and its 3 am here ๐Ÿ˜”
  • bayazidahmed
    bayazidahmed
    Hmmm...
    Lets leave the issue of bulkiness and weight behind for the time being.

    I was thinking about the wireless part...
    Bluetooth Class I range is 100m and Wi-Fi is 35m or so. Both are insufficient. I dont know how we, specially I got dragged into thinking that we could use bluetooth or wi-fi. May be because we just hear it everyday in our daily life and that made my mind think in one direction. anway you all must be knowing that communication simple and effecient communication is best possible ony through radio. There are many examples of radio controlling, the simple one of a remote controlled toy car.
    I think we'll have to use only radio for controlling the bot, and the data we get fom the bot should be in AM or FM (preferred). Simple transcievers would do fine on both ends, we only have to define which signal means what (in simple words, protocol).

    Think on it.. Details Later...
  • xheavenlyx
    xheavenlyx
    Thats a good thinking. i have though of that sometime ago. However, I think we have to include both, WiFi and FM transmission. Here is why:

    1. FM communication is excellent at long range, but the problem is bandwidth. The data transmission rates is hell for the amount we need to transfer at high risk situations.

    for example: The bot is working fine with FM communications for command to move x distance with x speed in x direction, and we are receiving the temperature, location of the bot etc.

    Now we find something, we need the video transfer, we have to send audio, receive audio, need robot data, position, alignment, temperature, send motion commands and maybe move the arm. This much data is impossible to send by a few FM transmitters.

    BUT, we CAN use a FM transmitter like 477 MHz, which has a good range and good transfer rate, but we might have to use a few of them.

    Initially the reason we thought of Wi-Fi or BT was the fact it was easy to connect it to the PC and program it for communication. But yes we can add in a 477 MHz for emergency or critical tests and communication.
  • bayazidahmed
    bayazidahmed
    What should I discuss next?
  • bayazidahmed
    bayazidahmed
    Only 3 were active here and now of these 3, 1 is missing... How is your fever ash?
  • xheavenlyx
    xheavenlyx
    Ahmed, you have really contributed a lot! Now, in the next 3 days I will make a document writing down the things we discussed, and making a rough plan of what components will be present. Ofcourse, we can change it in time, we have to, there are always changes.

    I want to know if you are familiar with gmail and Google documents? If not then I recommend taking a look. I will keep one file open for changes and the other un-editable for sharing.

    Our next goal would be to design the chassis and the body. But before that we would have to research or know a bit about previous similar bots around. It would be nice if you find some links, i will too.

    ===============================================
    OBJECTIVE 1.1

    Research similar bots and collect useful data. This can either be done in one week or two.

    OBJECTIVE 2

    To design the body and consider things like motors and track drives etc. (later)

    ========================================================
    (I never noticed we can change color. Good for showing important points)
  • bayazidahmed
    bayazidahmed
    Thank you! And you have contributed a lot too. Where is the other member?

    Heard of google documents, burt dont worry, i learn things b looking at them. Almost all my knowledge of electronics and computers (including programming) has been gained onl by looking!

    I am sorry to say I wont be able to do research because, hold your breath, I use dial up connection!

    For body and chassis design, we'll have to rope in mechanical people, or are we doing it ourselves?

    For the time being I'll work on the block diagram for this thing. What say?
  • xheavenlyx
    xheavenlyx
    Excellent we can have the rough block diagram starte rite now itself. I dont know where the other 9,519 members are, but anyway this is ok for now. We can go slow for a while because I got my thesis deadlines coming up too ๐Ÿ˜

    I am going to college tomorrow, so I will know my time table.

    Its ok, I will be doing the research side by side, and whatever I find Ill post it here, or email them to you. Till then carry on with the block diagram.
  • Ashraf HZ
    Ashraf HZ
    *comes from behind bush*
    Boo!

    Great progress ๐Ÿ˜€ My apologies.. my fever is slowly subsiding, but I'm in the midst of my end of semester exams. My brain hurts!
  • xheavenlyx
    xheavenlyx
    Its ok, concentrate on the sem, I know how it is ๐Ÿ˜€ My thesis is slowing down these days. We can contribute little whenever we can.
  • xheavenlyx
    xheavenlyx
    We will keep this alive. I am still working on something. will post on it soon.
  • Ashraf HZ
    Ashraf HZ
    try to post up the Google Document thing.. I'll add stuff to that too if needed ๐Ÿ˜€
  • xheavenlyx
    xheavenlyx
    Ash you can add stuff here. Because the Google doc will take some time. Dedicating time to this project can get difficult sometimes. I will soon, condense all the info and post it soon, as a pdf or in a Gdoc.
  • xheavenlyx
    xheavenlyx
    I just came across an excellent storage problem. Considering the fact that we will be using the onboard hardrive for log files, AI programming, and possibly video, I have found a good solution for a heavy drive.

    This is what a normal laptop drive looks like:

    [โ€‹IMG]
    And this is what the Seagate S1 5GB Microdrive looks like:

    [โ€‹IMG]

    Why this instead of a flash drive? Well, 1. Flash drive will take up USB space, and 2. We do not want to waste the IDE slot on the motherboard.

    This Microdrive can be connected to a standard IDE slot using tha ATA protocol.
  • xheavenlyx
    xheavenlyx
    UPDATE: Objective 1.1 has been completed. We now know what the robot will constitute. Now something important:

    Something thats been irritating me for sometime is, are we sure we need to build a rescue robot? What other ideas do we have? Like something dedicated to Video processing? like a security bot, with plastic pellet guns, and siren etc etc? I am having doubts for the rescue thing. Its just too redundant, people do better work when it comes to rescue task.


    Suggestions are welcome.
  • Ashraf HZ
    Ashraf HZ
    Interesting find on the Microdrive! Technically its also a "flash" storage though.. *grin*

    Looks like we have a dilemma on the robot's function. How about we make the robot modular? Meaning.. you can use it for different purposes by changing the output transducers modularly (by switching the arms for the pellet gun). And remember, the rescue robot doesnt have to be used for dragging people from fires or whatnot; it can be used to gain information in hard to reach places. Plus, Gohm mentioned:
    What about a gas detector? Can detect the threat of carbon monoxide, natural gas leaks, etc. that could be a risk to people entering area afterwards (scientists, rescue workers).
    Thus, it still has a valid function as a rescue robot ๐Ÿ˜€

    What we have to make sure is that the robot is highly maneuverable, runs for a long time on batteries, that it is able to send and receive information efficiently. Once we figure that out, the robot can be used for multiple functions and roles ๐Ÿ˜€
  • Ashraf HZ
    Ashraf HZ
    A word of warning about the Google Docs. I was checking it out.. apparently, if we create a google doc using the CE Mail, we can only invite collaborators and viewers from those having CE Mail. In this light, I tested with a normal gmail address.. and turned out we can't invite people from CE Mail ๐Ÿ˜‰ Kinda weird though.

    Also, I checked out the google sites thing, made a CE Lab page @ CE Labs Projects

    I put it has public view. However, I think it has the same problem of same domain collaborators only. Shucks.. lol.
  • Ashraf HZ
    Ashraf HZ
    Eek, sorry for the triple posting. I checked out the laptop service manual Acer Extensa 5xx Service Guide - Service Manual Free Download

    Some possible things of interest include the I/O address map and other channels ๐Ÿ˜€ (and a guide for disassembling the thing).

    I think this is what the motherboard layout would be like, along with the connectors.

    Top View:

    #-Link-Snipped-#

    JK1 AC Adapter Connector
    BT1 RTC Battery
    CN20 Keyboard Connector
    CN19 Touchpad Connector
    CN18 HDD Connector
    CN17 Fan Connector (reserved)
    CN16 CD-ROM Connector
    CN15 FDD Connector
    CN14 CPU Connectors
    CN13 PCMCIA Socket
    CN12 Golden Finger for Debug Board
    CN11 Power Switch
    CN10 LED Board Connector
    CN9 LCD Connector
    CN8 Internal Microphone Connector
    CN7 LCD Cover Switch Connector
    CN6 Port Replicator
    CN5 USB Port
    CN4 Video Port
    CN3 PS/2 Port
    CN2 Serial Port
    CN1 Parallel Port

    SW1 Settings
    Switch 1, Switch 2 Default at OFF setting, un-configurable.

    SW2 Settings
    Switch 1 ON: OEM BIOS
    OFF: Acer BIOS
    Switch 2 ON: Bypass password
    OFF: Check password
    Switch 3, Switch 4 OFF, OFF: US keyboard
    OFF, ON: European keyboard
    ON, OFF: Japanese keyboard

    Bottom View
    #-Link-Snipped-#

    SM1 Modem Socket
    CN23, CN24 Charger Connector
    CN22 DIMM Socket 1
    CN21 DIMM Socket 2

    Lots of connectors is always good *grin* xhx, when you have time to take the laptop apart, can you give us some live pics of the system board? Also, is there any way to use the Port Replicator connection for other uses? Thats like a docking thing right.

    My last exam paper is on sunday. After that, I plan to do some possible rough designs of the CE Bot (on mspaint, of course ๐Ÿ˜‰ ) CEans, now that the CE shirt contest is over, start designing the CE Bot! Winner gets a.. um.. will leave that to biggie ๐Ÿ˜‰
  • xheavenlyx
    xheavenlyx
    1. You are a fuk!ng genius! lol, good work on the mother board pinout and layout, and all other outs. This diagram can be useful for reference.

    You know, I have just 2 minutes to reply. So ill be fast and will read in detail a bit later.

    You are spot on with the modulerarity (fish spellings)!! I had forgotten that. good idea, we will keep it HIGHLY modular, and customizable. Recently there was a product, which was a small processor in a box, and u can attach anything to it. LCD, GPS, sensors, blah, and other blahs. And make it do anything with symbol programming or direct coding. Its actually an electronic device, commercial and hackable. Ok so now we know that.


    And yea, the hard drive, Microdrive is actually a miniature hard drive, its not exactly flash, it looks like one though. Here is an extract from the datasheet:

    These drives provide the following key features:
    โ€ข3,600-RPM spindle speed and 2-Mbyte buffer combine for superior performance.
    โ€ขQuiet operation. Fluid Dynamic Bearing (FDB) motor.
    โ€ขGiant magnetoresistive (GMR) recording heads and EPRML technology, which provide the drives with increased areal density.
    โ€ขState-of-the-art cache and on-the-fly error-correction algorithms.
    โ€ข1.5K Gs nonoperating shock, and 200 Gs operating shock.
    โ€ขSeaToolsโ„ข diagnostic software performs a drive self-test that eliminates unnecessary drive returns.
    โ€ขThe 3D Defense Systemโ„ข, which includes Drive Defense, Data Defense, and Diagnostic Defense, offers the industryโ€™s most comprehensive protection for disc drives.
    Anyway, ill be checking out the labs page rite now and reply a bit later.

    Again good work!!!! Realy.
  • Ashraf HZ
    Ashraf HZ
    But xhx, according to Wikipedia, Microdrive has quite a number of disadvantages ๐Ÿ˜”

    Disadvantages of Microdrives
    • As of 2006, Microdrive's capacity advantages were exceeded by CompactFlash cardsMicrodrive - Wikipedia, and USB flash drives.Microdrive - Wikipedia
    • Being mechanical devices they are more sensitive to physical shock and temperature changes than flash memory, though in practice they are very robust and manufacturers have added several features to the more recent models to improve reliability.
    • A microdrive will generally not survive a 4 foot (1.2 metres) drop onto a hard surface where CF cards can be thrown off high-rise buildings and still function. Using a soft packaging (e.g. Polystyrene - Wikipedia foam) can allow survival from a longer drop.
    • Newer Microdrives have a mechanism to hold the heads off the platter while the device is not in use. Early IBM models do not have this - when one gently shakes such a drive one can hear the heads click from side to side.
    • Microdrives are not as fast as the high-end CompactFlash cards; they generally operate at around 4-6 megabytes per second while high-end CF cards can operate at 20 megabytes per second. This may cause problems for photographers who shoot sequences of large images in rapid succession.
    • Not designed to operate at high altitudes (over 10000 feet), but can be safely used on most commercial aircraft as cabins are generally pressurized.
    • Only high capacity models are manufactured, as it is not profitable to make low-capacity Microdrives. At the end of 2005 only capacities above 2 gigabytes are manufactured while 256mb and 512mb CompactFlash cards were still in production. Lower capacities are still readily available second hand on eBay - Wikipedia but these are usually the same price as CF cards of the same size.
    • Unlike flash memory, microdrives require power even when no data is being transferred to them to keep the disc spinning. As a result many devices such as the iPod mini leave the drive switched off for most of the time while periodically starting it up to fetch data from it to fill the device's buffer. Microdrives will switch off after idling for more than a few seconds to counter this problem however this means that more time is lost constantly spinning the drive up. This effect would be particularly problematic if an operating system is being run from the drive. However the drive can be forced to stay running if the host device is programmed to write random bits of data to it.
    • Certain bus-powered CF card readers lack the power needed to run a microdrive although they do take CF II cards, when using such a device it will usually be detected by the host but errors will occur once the user attempts to access the drive.
    • Microdrives also require some time to spin up, this is very low when compared to regular hard drives but not as fast as flash memory.
    • Since Microdrives are often integrated in another device this can cause trouble if the drive breaks, it is usually the most fragile component of the device and if the device is out of warranty it can be very difficult to replace the drive
    From Microdrive - Wikipedia

    In light of the fact we what the robot to be robust, will the Microdrive still be ok after rough treatment?

    On more thing; can we use the PCMCIA slot for the wireless transmission? Perhaps a pre 802.11n card. Funny you mentioned GPS.. I was thinking of the feasilibility of adding that feature on the robot last night. just2rock, if you are reading this, can GPS be implemented in robot effectively?
  • xheavenlyx
    xheavenlyx
    Excellent. Thanks for clearing that up. We will be using compact flash, if possible, sandisk 8/16 GB or higher NOR type can be used, connected to the normal IDE drive (if possible to connect, we might as well use the slot rather than keeping it unused.

    Bythway, check the Labs Page. It was also an awesome job you did. Better than the GoogleDocs. I tihnk why others (non CE members) are not allowed is because Google wants that space for Teams and Groups to share among themselves, Its just a guess. Cuz if everyone starts visinting, bandwidth can be overloaded.

    Again, thanks for the CE Labs!!! CE Labs Projects
  • Ashraf HZ
    Ashraf HZ
    No prob ๐Ÿ˜‰ Good work on adding more content to it!

    But remember, only those with CE Mail can edit. Not all CEans have it (since accounts on Crazy Engineers are not linked with CE Mail, I believe). Plus, I set it to public so everyone in the world can view. So lets assume CE Labs is a temporary place until Biggie can add a projects module to the vBulletin system here ๐Ÿ˜€ Once we can do that, we can easily set permission settings so only those members involved with projects can edit files ๐Ÿ˜€

    On a related note, assuming more CE Teams are created (eg editors, mods, promoters), you can have private/public sections in Google Sites using the CE Mail system.. if they all have that in the first place ๐Ÿ˜€ Though ideally we'd want everything integrated within Crazy Engineers website. That can be done later in the future I guess!
  • sanih
    sanih
    can i help you?
    i have knowledge about image and video processing with matlab.
  • xheavenlyx
    xheavenlyx
    Your idea for individual places for each CE Team is good. But we can keep it private only on the global level. All CE Team can see eachothers pages since many CE's have more then one task. I think thats what you meant.

    Anyway, I will check if one portion of CE Site remains private (Editorial) and the other public (Labs).

    Bytheway, if you get time Ash, add something about the project.

    @Sanih, You can help, and when we get to the point of discussing the OS then you can add in. Anyway, you can contribute at anytime you like, though I think you should read some previous posts on the topic.
  • Ashraf HZ
    Ashraf HZ
    Welcome aboard, sanih ๐Ÿ˜‰

    Ok, I just finish exams! Now can spend lots of time on Crazy Engineers, hehe. Will add stuff on the project soon, xhx. Btw, theres this nice article I came across. One of my engineering buddies suggested taking a look at soccer bots. They have similar objectives with ours in term of wireless communication system from robot to main computer (and other bots), image processing with cameras, etc. I think one of the models have laptops in them too. In fact, its quite scary that the ideas there are darn similar (like using the PCMCIA wireless card). Its a good read.. hopefully it can guide us in our own project.

    oh, and ahmed.. it also has flowcharts ๐Ÿ˜€ check them out!

    #-Link-Snipped-#

    I'll try to find links to robots that utilize the tracked locomotion system. Anywayz, I'm kinda afraid we make this project too complicated, hehe. What I suggest is we work on the very simple stuff first. Future versions can have the advanced features ๐Ÿ˜€ However, does not stop from getting thoughts from everyone... so post your crazy ideas!

    [EDIT]
    Has anyone used the wings3D software before? #-Link-Snipped-#
    Might be good for modelling our robot, just to show some concepts. I planned on trying something with the Alibre CAD software to kick start the design process. It was free the last time I used it ๐Ÿ˜‰ I believe there are CEans here who are experienced with CAD too.

    [EDIT 2]
    Wow, check this Google Site out. Its designed specifically for team projects:
    #-Link-Snipped-#

    Looks like our CE Labs page still has a long way to go, haha.
  • xheavenlyx
    xheavenlyx
    Excellent, and yea, I PMed you about the RTOS, you know about it already ๐Ÿ˜€

    Anyway, I agree its getting complicated, so we can concentrate on something small plus and make it modular, like we can add anything else later if we want to.

    So there are two very important things now.

    1. Designing the body, and choosing minimum of neccessary hardware. rite?

    2. Designing the software part. What should be processed onboard what sould be processed offboard.

    Is it right?


    ======

    Take a look at this:
    https://demo.projects.zoho.com/login.do (username and password at bottom)
  • Ashraf HZ
    Ashraf HZ
    Ok, Ive created a CE Projects thing at Zoho. Using the Free package, I can only do one project. Other limitations include the 100mb space limit, which I think is high enough already!

    xhx, can you pm me an e-mail add you'd like to use to access the projects page? I'll add you as a member. I'll invite biggie too! We can test it out together and see what its like. The place is here:
    #-Link-Snipped-#

    Heres the list of different plans available:
    #-Link-Snipped-#

    I think we can aim for the Basic package if we finally choose Zoho. I certainly wont mind chipping in for the $8 monthly charge ๐Ÿ˜€ When we get more active projects, we can aim for the Express package ๐Ÿ˜‰

    But anywayz, back to topic. Sanih pm'd me about the use of the I2C bus.. that should be no problem, I believe. Won't really conflict with anything else ๐Ÿ˜‰

    So there are two very important things now.

    1. Designing the body, and choosing minimum of neccessary hardware. rite?

    2. Designing the software part. What should be processed onboard what sould be processed offboard.
    Yep ๐Ÿ˜€ That should form the nucleus of the whole project.
  • Ashraf HZ
    Ashraf HZ
    If CEans are wondering about the status of this project, me and xhx are still doing on going testing at both Google Sites and Zoho Projects. Hopefully we will be done in a couple of weeks ๐Ÿ˜‰

    In the meantime, feel free to contribute to the discussion. Perhaps you can draft a rough design of the bot? Remember to look through the posts in this thread!

    here is the Google Site link: CE Labs Projects
  • Ashraf HZ
    Ashraf HZ
    #-Link-Snipped-#

    ^ A sample CE bot model using #-Link-Snipped-#. It took a lot of fiddling just to extrude the shapes properly. I suppose this program can only be used to draft ideas without the need of accuracy, cause it's pretty hard to get used to the views. I'll try out Blender next, and finally Alibre (which is a true CAD software). I really miss using Catia V5 ๐Ÿ˜” Oh, did you guys know V6 is coming out soon? I hope that'll drive the price of V5 down substantially!

    If your wondering why there is a hockey stick at the top, it was supposed to be a flag pole. But I dragged some kinda node and it bent the shape. I'll just let it be.. haha. Maybe you guys can try it out? I bet you'll have better luck than me ๐Ÿ˜€
  • Ashraf HZ
    Ashraf HZ
    #-Link-Snipped-#

    Okay, I skipped the Blender software.. too complicated to learn quickly ๐Ÿ˜› Above is part of the tracked wheel system designed in Alibre, didn't take me long to do it. If you have learnt CAD software before, Alibre is relatively easy to understand. You can download it for free #-Link-Snipped-#, but you'll need to register first. Its a 30 day trial of the full software before it disables some features (like assembly). I think theres a register-free edition #-Link-Snipped-#.. am downloading it now to check it out.

    I think I need some more time to learn the Blender software.. its not really a CAD software, rather a modeller and animator of some kinda. But you can get really awesome looking outputs with it!
  • raj87verma88
    raj87verma88
    Nice design ash. you can also add one more set of wheels and chain at an inclination of 45 degrees with one end. This will be free to move and in case the bot falls in a pit, it will make the bot do a somersault and get out. This will increase the reach.
  • raj87verma88
    raj87verma88
    Using of WiFi will be suitable. The IEEE 802.11y is estimated for a release in June this year. It's range(radius outdoors is 5000 m), 3.7Ghz, throughput (typ) 24 Mbits/s, data rate (max) 54Mbits/s.
    The long range WiFi my be better option for this project though.
  • Ashraf HZ
    Ashraf HZ
    Thanks for the input, bro! The 802.11y is an interesting choice, though I kind of worry about it's power consumptions. We will compile all the possible technologies soon and see their pros and cons.

    Raj, which CAD software do you use at your uni? Can you try out your wheel and chain idea and post it here? ๐Ÿ˜€ Me still a rookie when it comes to CAD, hehe. Today I was testing out different softwares that are freely available on the net, so we can easily share the data files.. wasn't really aiming to design possible ideas yet. You know any other good free CAD software? I might try BRL-CAD out.
  • raj87verma88
    raj87verma88
    We use AutoCAD and ProE but i will learn Solid Works Catia and Ansys(an analysis software) in my holidays.
    Yeah sure i will but it may take some time as my end sem exams are starting. They will be over on 17th of the next month.
  • Ashraf HZ
    Ashraf HZ
    Oh, best of luck bro! ๐Ÿ˜€
  • xheavenlyx
    xheavenlyx
    Ash, did I tell you before those designs are reallllyy good. you must have worked hard on it in Google sketch, since making a grove is a little difficult for me still. and on my Vista crap, Google Sk does not work, have to find out why.

    I can work mainly on AutoCad for drawings.

    Raj, Catia, is one hell of a bomb. And Ansys!? wow both are crazy softwares. Ash you know, Catia is used by Boing to design their 747/777's ! ๐Ÿ˜€ sadly it's kindof not free: Catia MD2 (Basic?) costs about $14,000 ^_^ plus 14% every year for renewals. But if we are not using it for commercial design then its a different matter (I guess).
  • joe3204
    joe3204
    if the bot is fitted with tracks (or something on those lines) won't it consume more power as compared to wheels? tracks will have more surface area in contact with the ground and hence friction will be more. how about using independently suspended wheels? they'll be more suitable for rough/uneven surfaces...
  • xheavenlyx
    xheavenlyx
    As for 802.11y. Its seems like a good choice until it comes to implementation which is very very new and what IC's? Programing it will be new?

    And as Ash pointed, we will compile pros/cons soon, moreover, we shoild also get info on what modules are available in the market which impliment WLAN and compare them too.

    Till then here is the wiki on 802.11a/b/g/n/y : IEEE 802.11 - Wikipedia

    EDIT:

    I tried looking for some info on this, but mainly the wiki gives info on ranges. Power consumption may vary a bit between different vendors and implementation IC's.
  • xheavenlyx
    xheavenlyx
    Jow, thats a valid point. Yea, we didn't think of it. I think everyone should read this for an idea:

    #-Link-Snipped-#

    What do you think guys?
  • Ashraf HZ
    Ashraf HZ
    Catia V6 is coming out soon ๐Ÿ˜› Ah, I didn't do the grooves in Google Sketch. Used Alibre for that. Though, I'll try working on G.Sketch more.

    Ah shucks, I was looking forward for the threads.. better looking ๐Ÿ˜€ Besides, what steering method are we using? differential or rack & pinion?
  • raj87verma88
    raj87verma88
    Rack and Pinion will be better
  • raj87verma88
    raj87verma88
    Never heard of differential as a steering method. Rack an pinion is the most common steering design. You can get more detail on #-Link-Snipped-#
  • joe3204
    joe3204
    found a link for differential steering..seems wheel chairs use the same system

    A Tutorial and Elementary Trajectory Model for The Differential Steering System
  • raj87verma88
    raj87verma88
    Thanks for the link joe.
    @ash and xhx. It seems the project now progressing rapidly. I have some designs in my mind, but won't be able to put them to paper till the end of next month. I am going to join a Robotics course with Appin and will be paying the registration fee tomorrow. This is the link to their site and the course that I will join. Just go through it and tell me if my joining it will be any help to you.
    #-Link-Snipped-#
  • Ashraf HZ
    Ashraf HZ
    Well, tanks essentially use differential steering ๐Ÿ˜‰

    We could technically compromise with the tracks and wheels. How about using 6 wheels? (3 on each side). That'll still give us traction and avoid getting stuck over large bumps. Steering both the first pair and the last pair of wheels can give us awesome maneuverability too! I've seen some modern APC's designed like that. Oh btw guys, the robot doesnt have to go SO fast. Just less than walking speed is sufficient. Yes?

    By the way, can you guys understand this stuff?
    #-Link-Snipped-#

    It got too complicated as I scrolled down =P
  • Ashraf HZ
    Ashraf HZ
    raj87verma88
    Thanks for the link joe.
    @ash and xhx. It seems the project now progressing rapidly. I have some designs in my mind, but won't be able to put them to paper till the end of next month. I am going to join a Robotics course with Appin and will be paying the registration fee tomorrow. This is the link to their site and the course that I will join. Just go through it and tell me if my joining it will be any help to you.
    #-Link-Snipped-#
    Dude, its an excellent course. Hopefully you'll gain a lot of experience from this =) And it'll help the CE Bot for sure!
  • Ashraf HZ
    Ashraf HZ
    Sorry for the triple posting!
    I initially thought of suggesting a hexapod type of locomotion, but I realise we'll be carrying a lot of equipment on board. I guess we'll be sticking to wheels and/or tracks.

    On to power supplies. I think the best bet is to use Lead Acid, like the ones in cars and motorbikes. In fact, using the the latter is quite suitable. Should be powerful enough to power the DC motors.

    As an alternative, Nickel metal hydride can be used too. It'll work in high current situations (with low internal resistance), and can be recharged a lot.

    There are other types.. zinc, alkaline, lithium-ion.. but I think their cons outweigh their benefits when we want to apply them to our robot. Regardless, I'll update these info on the celab.tk website.
  • joe3204
    joe3204
    found this link on batteries for robots. it has the dirt on all the batteries How to Build a Robot Tutorials - Society of Robots
  • Ashraf HZ
    Ashraf HZ
    Thanks for the link, joe! It confirms the benefits of Lead Acid & NiMH. I'll be sure to check out the energy calculators too!

    Updating on the 6 wheels idea (kinda like the Mars rover):

    The first pair and the last pair of wheels will have a DC motor each. These two pairs will be steered using rack & pinion. If possible, a single servo motor can accomplish this (by steering both at the same time, albiet at opposite directions). By steering the first and last pair simultainiously, we can have a much greater turning radius.. possibly having neutral turns as well.

    One question would be: wont the middle pair impede on the turning efficiency?

    Well, a good buddy of mine (eccentronix) suggested we allow the middle pair of wheels to freely move laterally (side to side). Doing that will align the wheels in the radius of the turn automatically, reducing any friction from sliding and skidding =) Each wheel will also have some sorta suspension (perhaps just springs) so it can go over bumps easily.

    This is a compromise between using tracked locomotion and wheels, I suppose. Got the advantages of both!

    I'll draw these ideas out, so it'll be more clear. Remember to keep checking out #-Link-Snipped-# for continous updates. Also, everything we discuss here will be added to that site, so chip in any ideas you have! =)

    What I suggest is to follow a format like this.. you have have ideas for a sepecific module, put a heading and place the ideas:

    Locomotive:
    I think blah blah blah..

    Power Supply:
    Blah blee Bloo

    Design:
    etc etc..

    What do you guys think? It'll make it easy for people skimming through the thread, as well as me and xheavenlyx to compile the ideas to put on the CE Lab page.
  • ice111
    ice111
    xheavenlyx
    Raj, Catia, is one hell of a bomb. And Ansys!? wow both are crazy softwares. Ash you know, Catia is used by Boing to design their 747/777's ! ๐Ÿ˜€ sadly it's kindof not free: Catia MD2 (Basic?) costs about $14,000 ^_^ plus 14% every year for renewals. But if we are not using it for commercial design then its a different matter (I guess).
    Hi xheavenlyx,

    I wan to know Catia is the same software as given on 3ds.com. I saw that soft at company where I went before for internship.

    Well I want to know, what is the planing for the CEbot building, I know anywhere can be designed on computer but what on building actual working prototype.

    - Ice
  • Ashraf HZ
    Ashraf HZ
    Indeed, it probably could be design on a computer anywhere, but we're at the "ideas" stage at the moment, which may take a while.

    Regarding prototyping, some of us could probably fabricate a small scale model to test out ideas. An actual assembly of the robot would probably done somewhere in India (see #-Link-Snipped-# for the draft project goals).

    Lets not impede the good progress we are having by worrying about offline collaborations yet. If we managed to complete the initial goals, the momentum can carry us to achieve the rest of the goals ๐Ÿ˜€
  • joe3204
    joe3204
    working on a design for the bot...will post it here when its complete....
  • Ashraf HZ
    Ashraf HZ
    joe3204
    working on a design for the bot...will post it here when its complete....
    Awesome! Can't wait to see ๐Ÿ˜€
  • xheavenlyx
    xheavenlyx
    Ash, to let you know, I am reading this place now a days everyday. And its going prettty well. Really well. This is getting good contribution, and I wish I could spend some more time here. I will do that soon after some college stuff is handled.

    And yes Catia is from 3ds.com, Dessault systems (spelllings?).
  • Ashraf HZ
    Ashraf HZ
    Dassault Systemes rocks ๐Ÿ˜€

    Anyways, bombs away! Take time to read below ๐Ÿ˜‰

    Communications
    I've been thinking quite a while regarding this aspect. The problem we have of choosing the right type of transceiver lies on how clear our requirements for the CE Bot are. What exactly do we want to transfer between the bot and the host computer? How long/far/fast will the bot be operating? What is the maximum amount of power can we allocate to the communication module? While all of us mull over this, I'll just list down the proposed parameters:

    Data outputs from Bot to Host
    - Video feed from Camera
    - Data from basic sensors
    - Proximity sensors
    - Sound
    - Telemetry
    --- Speed of Bot
    --- Distance Travelled
    --- Direction / Compass heading
    --- Acceleration

    Okay, here is where there will be two modes: Live Mode and Low Mode.
    In Live Mode, all these data will first be inputted directly in the system board, with some initial processing. It will then be transmitted to the host computer via a wireless communication module. What would appear on the host screen will be a HUD like display with a full colour video feed, will all the telemetry and sensor data. These data can be further processed to display useful information. For example, a terrain map can be derived from data collected by ultrasonic sensors.

    In Low Mode, minimal data will be transmitted to the Host, reducing the power needed. Minimal data may include a low quality video feed (perhaps monochrome), position of Bot, etc. The rest of the data from sensors will be stored on board the Bot for later collection.

    Data outputs from Host to Bot
    - Remote control of Bot
    --- speed and direction
    --- controlling of other actuators on Bot
    - Sound

    The basic model will be remote controlled from the host computer. We can introduce autonomous control in later iterations of CE Bot ๐Ÿ˜€

    Environment, Velocity & Distance
    I guess this is something we barely touched on. Being a tough, data collecting rover, the mission time would probably be extended (1 hour?). However, the total displacement from the host computer may not really exceed 100m. Further distances may be needed for future versions of CE Bot. I mentioned previously that the maximum velocity of the Bot would be less than walking speed. 1 m/s would do, yes? Mobility of the Bot will factor in on which communication module we can choose. There may be possible obstacles and obstructions in between the Bot and Host, including elevated land.

    Power Requirements
    Lets assume we choose the Ni-HM battery to power the main module. This includes the system board, the camera(s), and basic sensors. The system board on average may need around 18V @ 5 A (xheavenlyx, can you please verify the Acer? i'm using my old Compaq as reference, haha), which may require up to 8 cells of the battery (a guess).
    In this light, the communication module must not consume too much power, lest it may decrease the mission time somewhat. This can be remedied by adding more batteries, but we have to factor in the weight as well.

    From all this, we can safely conclude the following:
    - Data transferred is delay-sensitive, require a significant proportion of bandwidth, and must not be corrupted by attenuation.
    - Maximum effective range is 100m.
    - Effective signal propogation around obstacles and elevated terrain.
    - Balance between battery weight and power consumption (Low Mode can be used to conserve power).

    So far, Im preferring the use of WLAN, more so the 802.11 protocol.
    - To simplify its use, an Ad Hoc connection can be set up between the Bot and Host.
    - Digital modulation would optimize the efficiency of transmission, as well as the use of spread spectrum technology which reduces the effect of noise from interference, jamming and especially multipath fading (distortion of signals due to solid objects).
    - Data rates are also quite good; at minimum 1Mb/s.
    - However, the power requirements are still bugging me a little.
    - Range can be extended using smart antenna design. Size of antenna is not really limited.. maybe a maximum of 5cm radius on the Bot should be modest enough. Perhaps we can use some sorta of motion tracking/omnidirectional antenna?
    - 802.11 modules are easy to get and implement with the system board.

    Thinking long term, we can use the Host as an Access Point, and have many robots connected to it as a network. Complementing that, we can use multihop networks too.

    I'm still analyzing other communication methods though ๐Ÿ˜‰ Need to solve the power consumption problem. Please feel free to comment on the post. Be as critical as you can, so we can fix the needed design issues for the CE Bot as soon as possible!
  • Ashraf HZ
    Ashraf HZ
    Come to think of it.. am I fussing too much over the power consumption? I probably always think of that if I deal with portable devices. But CE Bot will be quite large and pack a lot of power in comparison, so does it matter for the first version of the Bot? If everyone agrees, we can just focus on range, delay sensitive propogation and transmission efficiency.

    In the mean time, we can look at the image processing aspect. Has anyone used this free Robot vision software called RoboRealm? (Robotic Machine Vision Software) Looks pretty cool.

    oh, I was just browsing through the forum here (RoboRealm - Roborealm and MATLAB) xhx, looks like you've been there already ๐Ÿ˜‰

    I really hope we can implement some sort of terrain mapping using ultrasonic sensors for this first prototype.

    [EDIT]
    We seem to be lacking some control flowcharts. Visual representations are always a good thing! I'll work on that this weekend. I'll try finishing off the basic work on celab.tk too.
  • xheavenlyx
    xheavenlyx
    Yea, lol, i as on that blog a while ago. 11 months. And programming can be a *****. I have to brush up on my c. Dont know how it will go.

    As for the flow chart. Its is a good idea if we make one.

    Which areas will you concentrate on?
  • Ashraf HZ
    Ashraf HZ
    I'm just gonna finish creating pages for all the research first, and add some details to each so everyone can read through them. I was hoping ahmed can post in the block diagrams, but he's been missing in action for quite a long time ๐Ÿ˜›

    I would really want to do some real life performance testing of a 802.11a/b/g Ad Hoc connection. I could probably test it between two laptops as a start. Can you suggest a methodology? Is a simple file transfer enough? Is there a way to have video streaming or conferencing between devices?

    [EDIT]
    For those who'd like to try out with the flowcharts and control flows, check out Dia:
    #-Link-Snipped-# (windows)
    #-Link-Snipped-# (other platforms)

    Seems good so far. You can export the diagrams in png, svg, etc.

    I also came across whats called a Unified Modelling Language software. It is used to create an abstract model of a system, graphically. It seems to be aimed towards software development. Might be useful for our CE: IM project ๐Ÿ˜‰ Heres a free UML software: #-Link-Snipped-#

    I'm thinking should also list all the software we will use for the CE Bot. Preferably they should be free, so that everyone can try it out if they dont have access to a specific software license ๐Ÿ˜› I've listed some at celab.tk already.. (eg Google SketchUp, EAGLE).
  • xheavenlyx
    xheavenlyx
    Good, eagle andsketch are fine. Can you possibly find something on the lines of Autocad?

    And ad hoc between two computers might not be enough. We might not get actual data on transfer speeds or power consumption. BUT yes for programming tests it can be used, as a really good test.

    I am also working on the flow diagram between sensors and processor.

    1. Sonar
    2.Video
    3. Motion encoder from the wheels to know exact possition.

    Arethere any more to include?
  • xheavenlyx
    xheavenlyx
    Ok, I have come across something really GOOD.

    I hope we agree on the fact that we would need an encoder attached to the wheel or motor to calculate how far the robot has gone and also for some small error calculations, this is called "dead reckoning" which means to estimate position of a bot without using external references. It has another huge advantage, that we can also use that data to map out the area roughly.

    Now the problem would come in when we have to encode the "turning" of the bot. How do we map that out? Sonar? That can be VERY challenging even if we use SLAM (Simultaneous localization and mapping - Wikipedia). So I just came up with something that would REALLY help to get a good idea of the bots movement.


    =========================================================
    Note that I am basing this idea on previous experiments I have done. Idea goes like this:

    We have 4 wheels (or 6-doesnt matter initially).

    One of the wheels will have an "Optical Sensor" mounted ON it, above the wheel. This can be from any optical mouse (preferably IC ADNS-20xx).

    What does the optical sensor do?

    Briefly, in a mouse it gives clear digital data on how much the mouse has moved on a surface and then translates that to pixel per inch for our computer screens.

    How will we use it on CE Bot?

    We will be using the same tech to measure how much our wheel has moved by placing the sensor just above the wheel.

    How do we get the direction??

    Simple, we have 2 ways to turn basically.

    1. One set of wheels pivot on their axis like a car. Here we mount it on ONE wheel, above its axis of turn. When the wheel is moving straight (Bot going straight) the optical sensor will give motion only on y-axis in dots per second. as the wheel turns, we get readings on x-y (north-west, north east). Just like a mouse moving on a mousepad! Only difference is mousepad is the wheel! ๐Ÿ˜€ You can try it urself by moving a toy car wheels in different directions on your mouse at home!



    2. As for differential steering (one moves slower than other). We would have to mount 2 of these and calculate using the data from both. I dont know if differential can be used effectively at all for 4 wheeled bot. As Ash has said we might be considering 6 wheeled rack pinion.



    For more accuracy, two should be used. The calculation behind getting the position accurately and mapping out is different problem and isnt very difficult.
  • Ashraf HZ
    Ashraf HZ
    Locomotion system
    Awesome stuff, xhx! We may need to modify the optical sensor positioning over the wheel, since the wheels' pivot point is sorta offset (not dead centre on itself).

    Can we also add shaft encoders too, via a optical tachometer attached to the shaft of the wheels (just like the normal mouse with the ball)?

    I suppose is indeed hard to use sonar to calculate it's position. I think its better used to sense the surroundings and draw a obstacle radar instead. Does not have to be too complicated for the first version.

    Regarding the 6 wheeled system, we still might need to implement a little bit of differential to the wheels that are steered just to make the steering more efficient (its possible since we have a motor for each wheel). Of course, one has to test this out to be sure ๐Ÿ˜›

    We can also make use of accelerometers to measure the turning force, and also some sort of gyroscope? Or is that a little too much ๐Ÿ˜›

    Software
    Regarding CAD, Alibre (the free version) is probably the closest one resembling the commercial CADs like Catia, Autocad, etc. There are free CADs that require you to program in C, but the learning curve might be a little too steep!

    However, theres one called MLCAD (Mike's Lego Pages). I only just tried it today. You can use lego parts (including the technics range) to create your own models. Damn nifty.. I have always used my old technic components to test out concepts for my projects. I initially planned to assemble together the 6 wheel with the rack & pinion steering with Lego technic, but I dont have enough of the crucial parts (they are either broken or lost over a span of 15 years ๐Ÿ˜›)

    I'll try drawing the 6 wheel idea, complete with the rack and pinion system. Its much easier that way, since the lego parts are already created! Don't need to bother with drawing your own gears, etc. Like Google SketchUp, its a great way to show concepts.

    Communications
    To solve the range problem for 802.11, we can either use omnidirectional or steered parabolic antennas. The latter can be steer to point to the direction of the host computer automatically using the data we got from xheavenlyx's optical sensor idea.
  • xheavenlyx
    xheavenlyx
    We may need to modify the optical sensor positioning over the wheel, since the wheels' pivot point is sorta offset (not dead centre on itself).

    Can we also add shaft encoders too, via a optical tachometer attached to the shaft of the wheels (just like the normal mouse with the ball)?
    Yes, thats rite, we would have to place the sensor just above the axis, not dead center.

    And why would we need a shaft encoder (the mouse tachometer is a clever idea but still the resolution is less than optical (about 10-20 points vs. 800 to 1200 dots per inch~!!!))? Optical are used for the same purpose, and tachometer easily would not give the turning of wheels too. Optical encoders give speed and direction when placed above the wheel. How exactly? I cannot write the explanation more than previous post, but will explain in detail when I start drawing the figure to demo it.

    And yea, using a gyroscope or an accelerometer (6 axis) will be VERY helpful. And they are also simple to implement (hackaday, or google the uses, interesting stuff). You know, implementing digital is always better, I have done the optical test myself, it might seem complicated here, but these functions are easy to implement and pretty useful ๐Ÿ˜€


    Please carry on with the drive system drafts. And I think Alibre complete is not free (? saw the website). Anyhow, we can use the demo if it isnt. Or might get a good sponsor and pay for AutoCAD plus for mechanical and hardwware stuff (I am praying for it ๐Ÿ˜€ )
  • Ashraf HZ
    Ashraf HZ
    Ah, you are right about the accuracy, haha. Resolution is indeed important!

    Theres a free version for Alibre. The functions in it are good enough for basic designing, except the "assembly" function.. which I think is broken.

    Here's what I cooked up using MLCAD. I've only used the basic lego technics components.. there were more advanced ones which I havent used before, so i'll leave that once I understand their functions.

    #-Link-Snipped-#
    #-Link-Snipped-#


    This is the 6 wheel idea, with a basic rack & pinion system (lego style!) at both ends

    *yawns* thats it for tonight!
  • xheavenlyx
    xheavenlyx
    Excellent. We will mostly use 6 wheel design. I think we should in time also look at how the middle set of wheels be used efficiently.

    Really good man, lol, you are working hard here. I think for the steering mechanism, we might need to use a strong torque high power servo motor.

    OR if we want to use differential turning method then each wheel can have an independent motor. These 2 have to be calculated for power consumption and other pro;s and con's. I still have to reead those links you sent me on steering mechanisms.
  • Ashraf HZ
    Ashraf HZ
    Locomotion- Steering
    Something we got to realise is that when a car steers, the turning angle for the left and right sides are different. If we want to steer to the right, the right wheel has to turn more than the left one, since the steering radius is different. Using the "simple" rack and pinion, the steering angles for both will be the same. It might not matter for small robots, but with turning accuracy important for CE Bot, it might! Modifying it to suit the above condition (for the robot) might take a while to figure out.. I'll leave that to the Mechanical engineers here ๐Ÿ˜‰

    I'm working out a different solution now. Instead of using rack and pinion, we use one servo for each turning wheel (4 in total). Thus, all wheels are independent of each other. The servo doesnt have to be very powerful.. we can use some simple gear trains to achieve the torque we need.

    Advantages of this:
    - Flexibility. We can program the turning angle on any wheel independently
    - Upgradability. We can add another servo to have a y-axis steer. Good for traction purposes ๐Ÿ˜‰
    - Weight & space savings. If you refer to the lego diagram, there are two racks as well as a long axle. They have to be made out of some kinda metal for strength. Removing them can save considerable weight, as well as allowing for something to be placed in the middle (batteries, perhaps?)


    To link the DC motors to the wheels, I propose we place the motors just above the wheel itself, so the shafts are in opposite directions. The shafts can either be linked by gears or a metal chain (like the bicycle ones). When the wheel is steered, the motor on top will be steered as well. I think using this approach will allow us to bring the turning axis quite close to the wheel itself. That should be a good thing, right? ๐Ÿ˜›

    It may seem like we are adding a LOT of weight with many motors.. but we dont have to use big and powerful ones. Using multiple small ones (with appropriate gear trains) will be equivalent to be using large ones, at the fraction of the weight.

    Of course, its possible a lot of power can be consumed this way ๐Ÿ˜‰

    I'll draw a sketch maybe later this weekend.

    Communications
    My dad just got a new Acer laptop (with Vista on it). I'll try installing XP on it so it'll match with my laptop, so we can do some wireless testing. Still working out the methodology though. The Netstumbler software might be useful to measure signal strength. I'm using a Wireless USB for my laptop.. that means I can at least fabricate an antenna for it ๐Ÿ˜›

    Tomorrow I'll try going to the components market to check out some small motors and sensors as well. They also have 2nd hand "white" & "brown" goods.. could probably salvage some rare components from them too.

    Speaking of which, if you'd like to donate your old VCRs or radios to the CE Bot project, please do so ๐Ÿ˜€ In fact, its possible to build a fully functioning robot only from the components in a VCR. Cool eh? ๐Ÿ˜‰ Robotics as a hobby is amazing indeed.
  • $..Aj..Rules..$
    $..Aj..Rules..$
    Ithink this is the link I was searching for..........!!!!
    Thanks to big K....!!!!
    can any1 temme....in brief wats the main part i need to start wit.....?
    I mean wat shud I do to be a part of this amzing link......?
  • Ashraf HZ
    Ashraf HZ
    Hey AJ! Nice to have you here, haha.
    For a description on what the CE Bot is, check here: #-Link-Snipped-#

    So far we are just discussing ideas. Please do take your time in reading the posts in this thread. I know you have a lot to catch up.. theres about 70 posts!

    If you post something here, you are automatically part of the project ๐Ÿ˜‰ Please do share your ideas!

    Locomotion
    Just to update on my previous post, the steering thing where two wheels turn with different angles is called Ackerman Steering:
    Ackermann steering geometry - Wikipedia

    Okay, its not as complicated as I thought! ๐Ÿ˜› Looks like we can reduce the number of servos after all. But I do wonder if we can still implement this system in the CE Bot..

    Got some books on Robot sensors.. will spend some time reading it tonight.

    [EDIT]
    Here's a pretty good link on RC model car handling:
    #-Link-Snipped-#

    I don't understand half of it, but it has nice diagrams ๐Ÿ˜‰ Theres stuff on Camber angling.. could probably achieve that on the CE Bot with extra servos (if we really need it).
  • xheavenlyx
    xheavenlyx
    The ideas you gave here are really good. But you know, we are making these assumptions by common sense, not excperience.

    I would like us to actually have a look at previous rescue/fighter bots which have to be rugged, and powerful to at least maneuver on a rocky terrain.


    For a start and to be fun I want you to see this video on Robot Wars. NOT SAYING WE FOLLOW THIS, but just to get an idea of the "size" when they look about 30 cm and 40kg, but in reality are BIg and about 100kg!! ๐Ÿ˜€

    Constrictor (Robot Wars Battles) - YouTube (Will blow you away!)
    Extreme 2 All Star Championship Grand Final - YouTube (Will ... i have no words!)
    Robot Wars Extreme 1 Annihilator 2 - Round 1 - YouTube (If you want to know the actual size @_@... unbelievable, it can eat a man....also see the house bot Sir Killalot! 216kg; petrol engine; lol )

    This is just the start we will have more info here to study present designs. Ash, the steering mechanism is a good idea, but we will need atleast a 1/2 HP DC motor for each wheel (not sooo big), so for this to work we need good calculations which we will surely do. I will post more info here AND on celabs.tk under a new subpage "Case Studies" ๐Ÿ˜€ Dude, watch that video above (as an example:: one robot consumes 700+ watts, 100kg)
  • xheavenlyx
    xheavenlyx
    The Lord of Distruction bot for me: RAZER!

    The World Championship semi Final of Robot Wars: The Second World Championship Semi Final 2 - YouTube

    Razor vs. "someone I forgot after watching the video"

    We have a LOT to learn from this guy! Control, Power of the weapon and speed.


    Presenting the best one yet when Razer KILLS (tearing apart and burnt - RIP) a house bot, house bots are supposed to be the arena gaurds and distroy the loser bots at the end or when they get cornered, Razer KILLS poor Matilda ๐Ÿ˜ (Invincible and unforgiving!) :

    Robotwars Uk - R I P Matilda - YouTube

    (Forgive me if I am going off topic for a day but this is HELLISHLY exciting stuff!)
  • Ashraf HZ
    Ashraf HZ
    Great links! I missed watching that show, haha

    I'll try getting links to safety/rescue/recon robots. I came across some before.. even those that have very similar objectives to ours, eg university student research, etc..

    Locomotion
    Regarding the motor.. I think a 1/2 HP motor is too powerful for a single wheel! ๐Ÿ˜› Probably a standard 12VDC (with gearing) is good enough. We don't want to carry too many batteries for the robot. The lead acid ones are quite heavy. Your getting too influenced by those combat robots ๐Ÿ˜‰

    For some calcuations, one can use this:
    How to Build a Robot Tutorials - Society of Robots

    Communications
    I found these links for a potential antenna designs for a 802.11 (2.4GHz) wireless modules:

    1) #-Link-Snipped-#
    2) #-Link-Snipped-#
    3) #-Link-Snipped-#
    4) #-Link-Snipped-# (practical implementation of spider-omni directional).

    I'll try getting polar charts for them. These designs are quite easy to fabricate. Probably the hardest thing is to integrate the N-type connectors to the WLAN modules (eg USB type). Thats what "hacking" is for! ๐Ÿ˜‰ If we choose a directional type, we'd have to figure out a way to rotate it to point towards the other wireless module automatically. As I mentioned in previous post, we can implement xhx's optical sensor idea as a compass.

    The reason I'm staying away from Low powered RF Modems for data (note: not remote control) transfer is their steep costs... perhaps $200-$300 a piece. Maybe when we get sponsors, we can purchase them (their baud rates are quite good) ๐Ÿ˜‰ Besides, I want to do the testing soon. I can probably build an 2.4Ghz antenna next month or so after I do some initial testing between two computers. Thats probably the only part of the robot subsystem I can test at the moment.. the locomotion system is probably out of my grasp (unless I borrow some wheels, DC motors and a drive chain from the Robotics lab at uni, and fabricate the ackerman steering column. Fat chance! ๐Ÿ˜› ).

    CEans, please do try out any ideas here if you have access to tools and materials. We need to get as many experimental data as possible ๐Ÿ˜€

    Flowcharts
    I'll draw a simple block diagram for the whole CE Bot later on Thursday night. That should give us an idea about why modular designs are useful ๐Ÿ˜€
  • Ashraf HZ
    Ashraf HZ
    Great links! I missed watching that show, haha

    I'll try getting links to safety/rescue/recon robots. I came across some before.. even those that have very similar objectives to ours, eg university student research, etc..

    Locomotion
    Regarding the motor.. I think a 1/2 HP motor is too powerful for a single wheel! ๐Ÿ˜› Probably a standard 12VDC (with gearing) is good enough. We don't want to carry too many batteries for the robot. The lead acid ones are quite heavy. Your getting too influenced by those combat robots ๐Ÿ˜‰

    For some calcuations, one can use this:
    How to Build a Robot Tutorials - Society of Robots

    Communications
    I found these links for a potential antenna designs for a 802.11 (2.4GHz) wireless modules:

    1) #-Link-Snipped-#
    2) #-Link-Snipped-#
    3) #-Link-Snipped-#
    4) #-Link-Snipped-# (practical implementation of spider-omni directional).

    I'll try getting polar charts for them. These designs are quite easy to fabricate. Probably the hardest thing is to integrate the N-type connectors to the WLAN modules (eg USB type). Thats what "hacking" is for! ๐Ÿ˜‰ If we choose a directional type, we'd have to figure out a way to rotate it to point towards the other wireless module automatically. As I mentioned in previous post, we can implement xhx's optical sensor idea as a compass.

    The reason I'm staying away from Low powered RF Modems for data (note: not remote control) transfer is their steep costs... perhaps $200-$300 a piece. Maybe when we get sponsors, we can purchase them (their baud rates are quite good) ๐Ÿ˜‰ Besides, I want to do the testing soon. I can probably build an 2.4Ghz antenna next month or so after I do some initial testing between two computers. Thats probably the only part of the robot subsystem I can test at the moment.. the locomotion system is probably out of my grasp (unless I borrow some wheels, DC motors and a drive chain from the Robotics lab at uni, and fabricate the ackerman steering column. Fat chance! ๐Ÿ˜› ).

    CEans, please do try out any ideas here if you have access to tools and materials. We need to get as many experimental data as possible ๐Ÿ˜€

    Flowcharts
    I'll draw a simple block diagram for the whole CE Bot later on Thursday night. That should give us an idea about why modular designs are useful ๐Ÿ˜€
  • Ashraf HZ
    Ashraf HZ
    All words and no pics makes Ash a dull boy ๐Ÿ˜Ž Hence..

    #-Link-Snipped-#

    Just playing around with that Dia software. You can choose from many flow sheets. The Cisco set is quite interesting, as well as the isometric one.

    Will add more pics soon.. ๐Ÿ˜€
  • Ashraf HZ
    Ashraf HZ
    Here's a bit of vehicle dynamics, drawn by the Inkscape software (nothing wrong with promoting free software!). The steering geometry and other dimensions for CE Bot can be roughly guessed here using the Ackerman Equation, where x is the centerpoint of rotation:

    #-Link-Snipped-#

    Using that equation, we can also set the dimensions of the CE Bot itself in relation to a targetted steering angle. I think this equation applies for low speed maneuvers.. it should be ok for CE Bot ๐Ÿ˜€ Any mechanical CEans want to give input on this?

    You'll notice that steering the front and rear wheels gives a very tight turn. As I've mentioned in my earlier posts, the middle set of wheels can be moved freely laterally. I'll draw a more detailed diagram next time.

    Hopefully this info helpful for those who plan to draft a CE Bot design with 6 wheels on CAD ๐Ÿ˜€
  • xheavenlyx
    xheavenlyx
    Ash, you gave the design on LEGO blocks a few posts earlier. That was really good, as the steering mechanism is implementable. On the design we will also look at how to form the outer chassis and structure on which we can place all the components. One thing I will do later (later meaning after college, only one week left! ๐Ÿ˜€ ) is to write down "which perticular sensors we will be using like Model number and collect their datasheets for dimensions, then we can start planning fitting this stuff in the CE bot and accordingly by wight choose the motor and wheel size AND the batteries!! ๐Ÿ˜€

    And Ash, thanks a lot for introducing the Ackerman Steering technique. That will be awesome for calculations! For more on Wireless (BT and/or WiFi) How to Build a Robot Tutorials - Society of Robots

    I am noting down the main checkpoints in Random below for a rough idea. Please do revise them when you can:

    =====================================================
    Ash - Test communication protocol. Donno if N- is finalized by FCC, but Latest Acer has N (One of my friend also told about it) So you check this. Please try to learn TCPIP communication basics if possible (1 day/week?)

    XHX - We might have to program our Bot on C or Python (Python can be an awesome choice too, I learnt basics in 1 hr! and EXTREMELY Powerful: LINK: #-Link-Snipped-# for Python used in Robots (OSS-Open Source Software)) VERY USEFUL! Full Robot simulation! See if you CAN.

    Ash - Further improve Steering design and description for final use.

    XHX/Ash - Write on celabs.tk about Sensors that will/can be used finally (common and good and cost effective). This will take long so we can do this side by side. Dont forget Datasheets for each.

    XHX/Ash - The motor calculation can come after sensors using that link you sent from Society of Robots. and then Power calculations. We will try to keep it minimum at first.

    Dont forget, if you can see the Pyro Robot Sim, if not Ill anyway tell you how it goes. I am leaving for Saudi after 1 week, so there I have time (no fast net connection, only forum and celab.tk)
    ========================================================
  • Ashraf HZ
    Ashraf HZ
    Nice work bro!
    I'm checking out Python, looks neat! Love the efficiency and portability. But it might take me a while to learn it.. I'm still studying advanced C functions in my free time ๐Ÿ˜›

    Maybe we can get some Pyro experts from that site to assist with our CE Bot?

    Me trying to get hold of an extra 802.11g USB module, and still searching for the schematics for my Aztech WL230 USB so I can "hack" it safely, haha. I've got two laptops (one with an in built webcam), and plan to take the latter in a drive around once the spider-omni antennas are finally fabricated. My final exams will end by 23rd June. Gosh.. arent engineering examinations perpetual or what?

    Im hoping for some input from the mechanical engineers here about the steering thing!
  • xheavenlyx
    xheavenlyx
    Yea, I have installed Python and Pyro, and started a bit, when I am in Saudi (Thursday), I will start it there. Today I am going to submit my Thesis draft, Just one more week to go, HECTIICC!!!

    And you will more people who have heard of MATLAB than Pyro... like the only person who came to know about RoboRealm was you ๐Ÿ˜€ I wish all CE were like you here.

    I would really want to do some real life performance testing of a 802.11a/b/g Ad Hoc connection. I could probably test it between two laptops as a start. Can you suggest a methodology? Is a simple file transfer enough? Is there a way to have video streaming or conferencing between devices?
    And yea, What "Hacking" are you talking about? Antenna? That is fine. I was thinking about converting the 802.11g to 802.11N lol. Anyway, Keep trying. If possible go to local comp shop and ask if they have junk hubs/switchers wireless, to salvage this connector from somewhere. College, computer shops, friends...anything ๐Ÿ˜€

    I will start Pyro and Python and let you. The most exciting part about these two is that they are completely modular!! ๐Ÿ˜€ And we can use C/C++ functions for tight timing applications, or even ASM (Assembly lang - learnt some in college and know it to control parallel port)
  • Ashraf HZ
    Ashraf HZ
    Haha, that thesis work seemed like forever eh? Good luck with it!

    Yep, I'm just gonna try soldering in the antenna cable connection. Also need to remove the PCB track that connects the existing embedded antenna. I've got some progress on researching how to do it, so should be no problem. My friend also has an extra wireless USB. So far so good!

    By the way, ASM isnt portable much right? Even if they are a little similar, different architectures use different type of ASM yea? I've only covered the Intel syntax. At most, we'd probably use assembly language in uC's, since their memory is very limited. The assembly language in PIC's seem easy to learn (I suppose because of the limited number of registers ๐Ÿ˜›)
  • xheavenlyx
    xheavenlyx
    Exactly, PIC's has a reduced instruction set than lets say 8051 uP or Pentium 4. P4 has grapix and mouse instructions too in ASM. As you said because of less registers and processing power.

    ATMELS ATMEGA8 has a good set and they are kinda precise than PIC as they solve 1 instruction per clock cycle. PIC does one instruction in 4 clocks. Moreover, I have read a firmware for a new ATMEL uC which also has a USB function, which is pretty ok (not THAT tough). (NOTE: some new PIC also has USB).

    We might (most probly?) be using a PIC or ATMEL uC with the ACER. Right? and yeaaa, ASM isnt very very different, we can know all the functions by reading their datasheets ๐Ÿ˜€
  • bayazidahmed
    bayazidahmed
    Sorry for the delay guys. I got real busy with my new job.

    Excellent development and good work from both of you.

    I'll see what I can do now. Though I am an electronics and communication engineer but I am good in electronics and computers so I will be able to help with the coding part easily. And the bad news I am not so good in mehcanical and I really dont care which steering we use.
    I havent read about the type of steering links given in the forum and in my opinion, I would prefer four independent dc motors which can be programmed individually, whatever type of steering you call it.
    For turning we simply dont give power to one side of motors and rotate the other side. This is highly flexible, trackable (especially for antenna to track the source, I dont know how can we track the height) and easily programmable.

    in btw, xheavenlyx, which city are u going to come in saudi?
  • bayazidahmed
    bayazidahmed
    There is something called dynamic C, Jackrabbit uC uses it.

    We write the program in C, this compiler converts it into ASM for the uC.

    The good thing about jackrabbit is, it has multi-tasking features, good memory and the main thing is, it has more number of ports and all ports are programmable as I/O (This is pretty good. We can control all the 4 motors using one uC and use this same uC for some different functions also like antenna tracking or in broader terms we can say anything related to movement can be controlled by this one uC, be it speed, direction, distance, antenna tracking, ...)
  • Ashraf HZ
    Ashraf HZ
    Welcome back bro! We've missed your inputs, haha.

    Interesting stuff about Jackrabbit. Are you referring to the BL1800? Quite difficult to find references to "jackrabbit" on the Rabbit website ๐Ÿ˜› I found the local distributor for Rabbit products in my area.. unfortunately they don't seem to give out a free sample ๐Ÿ˜” Cost wise.. BL1800 is around $50 I think.

    Regarding steering, the differential method wont really work well for 4 or more wheels, unless it has threaded tracks (like tanks). Threaded or not, it'll still face lots of friction, which makes the motors work harder than necessary. As a compromise, we have two "rack and pinion" steering systems at both ends. We may not achieve neutral turns, but the turning radius should be good enough to serve our purposes! We do intend to have a motor for each turning wheel.. but we still need to decide on its positioning (keeping in mind about the turning axis of the wheel, whether or how many gears we'll use, using universal joints, etc).

    Hopefully we don't need to worry about tracking the antenna if we are using omni directional ones. We'll see if the latter has a good enough gain.
  • joe3204
    joe3204
    Been out of circulation for a while, semester exams going on!! you guys have made quite some progress.
  • bayazidahmed
    bayazidahmed
    Yup I was referring to the BL1800
  • Ashraf HZ
    Ashraf HZ
    Here's some designs from the myPIC32 design contest (#-Link-Snipped-#) that can be useful for our purposes:

    Holonomic Mobile Robot for Under Vehicle Inspection
    #-Link-Snipped-#

    Model radio control system
    #-Link-Snipped-#

    PIC32 SunBot
    #-Link-Snipped-#

    We'll put them under the "Case Study" section of CE Bot at the CE Labs website. Thanks to Muffy for the original find ๐Ÿ˜€
  • xheavenlyx
    xheavenlyx
    I will be updating the website mostly, instead of posting the activity here. you know, it can get irritating posting the same material twice ๐Ÿ˜€. That is #-Link-Snipped-#

    So do read up the updated pages there, and Ash, thanks for keeping the mechanical side up and also the wireless communication. The tests would be awesomely helpful for communications.

    One last thing, Our most basic rule at the start will be using it to map out a random terrain and secondly to follow a person/object arround. After we concentrate on this we CAN expand it to the rescue part. (NOTEEEE i wrote this in 2 minutes, i will expand later, have to leave for something...)

    ==EDIT==

    Yea, I was telling that our main initial aim would be to finish the robot that can perform two very important tasks:

    0. Be completely modular. Meaning we can add/remove any sensor or actuator without facing (much) difficulties on software and hardware side!! (Very important as this can be a very good learning tool).

    1. Roam around an unknown terrain and build a map from all (most) of the sensor data. This map building can take place either on-board CEB (CE Bot) or off-board after relaying the data to the mother computer (wireless transmission).

    2. Be able to follow a specified 'object'. The 'properties' of this object is fed into the 'follow_it()' module. Like color, shape etc. All the while specifying what distance to keep between the object and CEB.


    Later on we can build on this to make it do other things which might be related to rescue stuff. Ultimately we are building it to learn so many things from this! (plus have a CE Bot that might be useful at places)
  • Kaustubh Katdare
    Kaustubh Katdare
    [Just a suggestion]

    With close to 100 posts, this thread is really big enough for newbies to follow. So, ash & xHx, can you continue this discussion in a new thread with the first one or two posts containing summary of this thread?

    [/Just a suggestion]
  • xheavenlyx
    xheavenlyx
    Oh, we actually realized it a bit but didnt think it was THAT big, now looking at the number of pages, and as you said 100 (!!) posts, I think we should make a new thread.
    In the new thread (Part 2) we can have:

    - A summary of what we did in a way that will only contain points not explanations. Because most of the important stuff is posted on #-Link-Snipped-#

    - What all (aprox) is left to do and will be doing.

    - Encourage them to go through #-Link-Snipped-#

    Ash, and others please add on to these points.
  • Ashraf HZ
    Ashraf HZ
    Yep, I guess those points are enough!

    We'll utilize the forum purely for discussions, I suppose. You are right, its tedious to post the same thing here and at celab.tk ๐Ÿ˜›

    Okay, so the CE Bot can be both autonomous and remote controlled, yes?

    Oh btw xhx, thanks for updating the site ๐Ÿ˜€ Regarding the tables.. I must confess I merely did the formatting in MS Word, because I was typing the info offline, from a book. I just copy-paste the whole thing ๐Ÿ˜› Is it possible to put CSS in the HTML there? That'll make things easier (and look more nicer).
  • xheavenlyx
    xheavenlyx
    Okay, so the CE Bot can be both autonomous and remote controlled, yes?
    Yea, it will be. As much as we can make it so. It will be tough, but atleast we will try and learn in the process!

    And, yea, lol, I think I have to make my tables in MS Word then ๐Ÿ˜



    As for creating a new thread. That might take a bit. I am taking a break from rigorous CE Bot discussion/planing, I had dreams last week...

    We gotta read the threads again and form it properly in one page. Hopefully we get other members involved again after the summery 2nd Thread.
  • Ashraf HZ
    Ashraf HZ
    Ok! My 2 week break has officially started. Starting from tomorrow, I'll try dedicating more time on the CE Bot ๐Ÿ˜€

    xhx, if you want, I can do the summarizing and start a new thread, since I'll be free ๐Ÿ˜‰
  • raj87verma88
    raj87verma88
    Ok, I finished with the Robotics course that I had mentioned earlier in this thread. All things are fine, except, that I am not good in programming.
  • xheavenlyx
    xheavenlyx
    Dude!! Raj, its ok! ๐Ÿ˜€ You can be active on the mechanical side itself. And please if possible (it will be) make a thread on your robotics course and your experience. We would gain a lot from it!

    And ash, if you can then please summarize, if you need help on certain pages, mail me or post it here. I will do my best.

    I was busy with doing something with CEcode (just realized we might not actually need the new google site, we can do with celab.) and if we need a wiki page for tuts and stuff, we can have it attached to CE. As for putting valuable Crazy Engineers code/software distributions we should have a Sourceforge/Google Code page, to keep track of things (its the usual method for Open Source software distribution). Ash your programming guide and my python docs will be moved to celab tutorials page or something under Programming (donno lets see).

    I just finished a Installer and creating .exe with Python will upload it as soon as i get back to dubai (connection is shit here).

    Next step will be to show you guys an awesome progie to apply our CE bot algorithms!

    Ash, as for the Ce bot after summarizing we will finalize steering methods from what you have researched. And when i get back to dubai i can install linux on my ACER laptop and start experimenting with Pyro (Its realllyyyy sucha cool tool).

    and Ash, thanks for sticking with the project! ๐Ÿ˜€
  • Ashraf HZ
    Ashraf HZ
    I wouldnt dream of neglecting CE Bot! ๐Ÿ˜›

    I'm quite stumped on how to summarize 100 posts of the thread. I'm thinking of just posting the stuff we have on the front page of CE Bot at CE Labs (the objectives, etc), as well as the things that we still need to discuss.

    Perhaps I could categorize the posts under things like "Programming", "Design ideas" etc, and put the permalinks of the posts. That way, those interested in a certain category would only need to read the posts that contain them. Nevertheless, this will still take some time, haha.

    Can't wait to see your progress with CE Code and Pyro, xhx!

    btw Patty, don't worry. Programming in robotics is easy to pick up. You just need to understand the logic needed!
  • sauravgoswami
    sauravgoswami
    Well why dont we ask Ashimo,how he would like to programme humans????
  • xheavenlyx
    xheavenlyx
    Yea ash! Your first point is ...to the point!! ๐Ÿ˜€

    You can give the same content as the main page of celab.tk (with links). and also your own interpretation of the content. Its ok if its short. The MAIN thing is on celab.tk. So in the end of the thread post the link ๐Ÿ˜€

    As for:

    Perhaps I could categorize the posts under things like "Programming", "Design ideas" etc, and put the permalinks of the posts. That way, those interested in a certain category would only need to read the posts that contain them. Nevertheless, this will still take some time, haha.
    And yes, we can have sub cat...Programming and Sensor etc BUT better give one line explaination and just the link to celab.tk/... (their appropriate categories.) BUT BUT you can do one thing with this thread:

    There are 6 pages....each page will have something important (dont read all...just skim thorough) and then just tell people what there is in each page (brief)...you know, I will try doing that too. For now just summarize and post links from our celab.tk sub pages.

    ---(For the programing stuff, keep an eye on "CEcode launched" thread...I am thinking of removing cecode from Google sites and putting it in Google Code proper so we can upload software with software control and bug tracking...just like coders use sourceforge....and Google code uses Wiki for describing code!!! ๐Ÿ˜๐Ÿ˜ as for the wiki you were talking about for articles and all, we can have that included with ce website)
  • KINETIC_JOULES
    KINETIC_JOULES
    I would like to be part of this CE Bot team. Is it too late?
  • xheavenlyx
    xheavenlyx
    No buddy its ok, its never late ๐Ÿ˜€

    But one thing you gotta do is try to read through the thread BUT only the longer posts from Ash and me. Gohm and a few more people have contributed as important as anyones, so read the first TWO pages. you will get an idea. ๐Ÿ˜€ It will take atleast 10-15 mins.


    Oh yea, and dont forget to visit: #-Link-Snipped-# for detailed info on each related topic.
  • KINETIC_JOULES
    KINETIC_JOULES
    xheavenlyx
    No buddy its ok, its never late ๐Ÿ˜€

    But one thing you gotta do is try to read through the thread BUT only the longer posts from Ash and me. Gohm and a few more people have contributed as important as anyones, so read the first TWO pages. you will get an idea. ๐Ÿ˜€ It will take atleast 10-15 mins.


    Oh yea, and dont forget to visit: #-Link-Snipped-# for detailed info on each related topic.
    Thanks, love! ^_^ I'll start reading. I was aware that I had to do some reading before I started to contribute to this project anyway. You must be aware that I'm no expert. . . but I will try!
  • KINETIC_JOULES
    KINETIC_JOULES
    *Still reading through* I'm aware that this will require A LOT of PCB design and a lot of computer science/computer programing. I'm still reading and from what I can tell, this is WAY out of my league, but I still want to contribute what I can.
  • Ashraf HZ
    Ashraf HZ
    Hi Kinetic, welcome to the team!

    The PCB design and programming is just a small part of it. We need some designs on what the robot might look like ๐Ÿ˜‰ Also, I remember reading your post about your headphone-in-hoodie project, which I think is quite cool! Its nice to see you've already mastered "soldering" ๐Ÿ˜€ We could sure use your creativity in this project!

    I'm really sorry, I'm supposed to summarize the posts so its easier to browse through. Like xheavenlyx suggested, check out #-Link-Snipped-#. Its a little more organized, haha.
  • raj87verma88
    raj87verma88
    I am not an expert on computer languages so will leave it to Ash XhX and others. I will like to summarize some details of this project that I have in mind.
    The Bot would be powered by a DC Geared motor ora servo motor
    Differential Steering
    We can fit Articulated hands on the bot and one SCARA in front which may act as the head(fitted with a video)
    The bot could be automated with various sensors for temperature, balance, height, sound, surface etc fitted to it. I will right the details about the sensors in a few days. But for this we would have to create a strong AI.
    If we want a part with motions in steps like walking then we will have to use stepper motor.
  • raj87verma88
    raj87verma88
    For sensors
    The IR Sensors
    advantages: cheapest and have an easy circuit
    disadvantage: line of sight problem

    same for laser only difference it is costlier than IR

    other sensors include TSOP(Thin Small Offset Packaging) and Photo diode (needs a high intensity source like hydrogen lamp or nitrogen lamp)

    If using the IR Sensor then we may use Op Amp 741C or LM324
    LM324:-
    # Quadruple Op Amp
    # 14 pin DIP(dual inallign packing) IC
    # Capable of interfacing 4 IR circuits to the micro controller

    for attaching motors we may use ULN2803
    it can accommodate 2 stepper or 8 DC motors.

    We may also use transducers as bot inputs in some places.

    For newbies "tranducer converts physical quantity into equivalent electrical or electronics signal" and "Sensors detect anything in their environment for a particular range"

    Here is a link to a thread which may be useful
    #-Link-Snipped-#
  • raj87verma88
    raj87verma88
    for making the bot autonomous we may use ideas from AIBO

    or a link for ideas about some sensors
    Autonomous robot - Wikipedia
  • KINETIC_JOULES
    KINETIC_JOULES
    ash
    Hi Kinetic, welcome to the team!

    The PCB design and programming is just a small part of it. We need some designs on what the robot might look like ๐Ÿ˜‰ Also, I remember reading your post about your headphone-in-hoodie project, which I think is quite cool! Its nice to see you've already mastered "soldering" ๐Ÿ˜€ We could sure use your creativity in this project!

    I'm really sorry, I'm supposed to summarize the posts so its easier to browse through. Like xheavenlyx suggested, check out #-Link-Snipped-#. Its a little more organized, haha.
    Soldering is quite easy. . . a 6 year old could do it! But, I don't know if I can contribute too much to this project, for I don't have the knowledge yet. I've looked at the link you gave me, and yes, it is easier to understand. As we progress, I may be able to figure out a digital rough draft or something. Hell, I might even have to break out my iMac in the other room. So. . . basically, tell me what I can help with and I'll do what I can. M-kay?
  • raj87verma88
    raj87verma88
    Hi Kinetic
    Let us hear your ideas on how the bot should work, what it should do and its look. Begin overworking your creative side. You will gain knowledge as the bot progresses provided you keep checking the thread regularly.
    P.S.. As Ash said, welcome to the CE Bot Team
  • KINETIC_JOULES
    KINETIC_JOULES
    raj87verma88
    Hi Kinetic
    Let us hear your ideas on how the bot should work, what it should do and its look. Begin overworking your creative side. You will gain knowledge as the bot progresses provided you keep checking the thread regularly.
    P.S.. As Ash said, welcome to the CE Bot Team
    Thanks, raj!
    I'll begin working on the design momentarily. I'm not sure when I will have it, cause I'll be busy today, but it shouldn't take me more than a couple of hours to do. I'll look back at what was previously discussed, and will work from there.
  • xheavenlyx
    xheavenlyx
    Yea, good you are reading the forums too, we dont want anyone to re post stuff that has already been discussed.

    You can also read about several already built robotic projects by people online, you can get a good idea. Specially this site is pretty good: How to Build a Robot Tutorials - Society of Robots

    @Raj

    for attaching motors we may use ULN2803
    it can accommodate 2 stepper or 8 DC motors.
    Yea, thanks for pointing this out. We need to look into good Motor Controllers IC's/Circuits.

    And Raj, write your post into sections with heading so its easy to integrate later on to our reports on #-Link-Snipped-#, like:
    Communications
    Sensors
    Operating System
    Motors Control System
    etc...
  • KINETIC_JOULES
    KINETIC_JOULES
    Thanks! I'll read that too. Is there any certain part that you would definitely like me to contribute to?
  • Ashraf HZ
    Ashraf HZ
    KINETIC_JOULES
    Thanks! I'll read that too. Is there any certain part that you would definitely like me to contribute to?
    We are deprived of chasis designs. Can you work on that aspect?

    At the moment, the robot will have 6 wheels (3 on both sides). The main bulk of components will be in the middle. We don't want the robot to be too large.. the exact size calculations will depend on the ackerman steering equation (which we havent done yet, but soon will). Maybe you can add a small (but tall) antenna, a camera, and a gripper thingy. Some sort of concept designs I guess ๐Ÿ˜€

    I've done a bare lego design here:
    #-Link-Snipped-#

    You don't need to use a CAD program. Any graphics program is ok. Even sketching on paper and scanning it is alright ๐Ÿ˜‰ If you have used Google SketchUp, that would be useful though.
  • KINETIC_JOULES
    KINETIC_JOULES
    Well. . . I would scan it, but my windows is being weird atm, and won't recognize my scanner device. I'll work on it. Can I use what you've already got designed?
    [EDIT]
    What I meant was, can I sketch on what you have?
  • raj87verma88
    raj87verma88
    Thats a good design buddy. Let me see. On Linux, ProE, Catia, Solidworks don,t work. Tried installing BRLCAD but could not. Now I will try MLCAD.
    By the way we can use these designs for the project report(google lunar).
  • KINETIC_JOULES
    KINETIC_JOULES
    ^_^ It is a great design. . . I just wish I had a decent program to design on.
  • Ashraf HZ
    Ashraf HZ
    @ Kinetic
    Yes, you can use it as a base. It looks a little too "ugly" and bare to be called a concept design at the moment. Hopefully you can beautify it ๐Ÿ˜‰ If your scanner can't be fixed, just take a digital shot of it. Anything works as long as we can see it clearly ๐Ÿ˜€

    @ Patty
    Don't be too concerned with those advanced CAD programs yet. We'll go into that later when we finalize the design. Its too time consuming to make multiple designs on CAD at this stage ๐Ÿ˜€ MLCAD or Google SketchUp should suffice. What problems did you get with BRLCAD?

    For the Google Lunar bot, it'll need some modification. Remember, CE Bot is was derived from the GLXP idea, but for earth-based applications. The ideas are similar (ie rough terrain, data communications, remote/autonomous functions, etc), but for lunar applications we'd need to consider the space environment. Things like very long range communications, ultra-efficient power supplies and electronics, special chasis design, extreme environment protection.. as well as how to land the darn thing in the first place. We may need to discuss these aspects for a while before putting in report ๐Ÿ˜€
  • KINETIC_JOULES
    KINETIC_JOULES
    I can't take photos of it either. . . screwy hp printer. . . my camera has a card, and the only way to read the card is through my printer/scanner.
    I thought we weren't going to make a lunar bot. . . or is it THAT modular?
  • xheavenlyx
    xheavenlyx
    but for lunar applications we'd need to consider the space environment. Things like very long range communications, ultra-efficient power supplies and electronics, special chasis design, extreme environment protection.. as well as how to land the darn thing in the first place. We may need to discuss these aspects for a while before putting in report
    wow, elequently(avoid my sp.) put!

    As for a lunar bot. Man, I wish it was that easy to make it a Modular system to include all the above aspects Ash pointed out. But no, we cant, working in high radiation/vacuum environment is difficult and costly. Actually really very very costly.

    But atleast we can concentrate on something, it can be a good learning process.

    Plus, we still have to seriously define a solid use of our Bot. At the least(and most importantly) it can be a bot which learns about the environment and relays the data back to the mother PC and deduces a map and path, and we continue from there on to define more purposes ๐Ÿ˜€
  • KINETIC_JOULES
    KINETIC_JOULES
    xheavenlyx
    Plus, we still have to seriously define a solid use of our Bot. At the least(and most importantly) it can be a bot which learns about the environment and relays the data back to the mother PC and deduces a map and path, and we continue from there on to define more purposes ๐Ÿ˜€
    Didn't you say it was going to be like a rover? Six wheels, 3 on each side? I've got the digital sketch that ash made, but what are we agreeing that the rest of it has. Like HOW modular is this thing going to be? What attachments is this thing going to have?
  • Ashraf HZ
    Ashraf HZ
    KINETIC_JOULES
    Didn't you say it was going to be like a rover? Six wheels, 3 on each side? I've got the digital sketch that ash made, but what are we agreeing that the rest of it has. Like HOW modular is this thing going to be? What attachments is this thing going to have?
    Yes, the rover will be doing the data collecting ๐Ÿ˜€ Its going to have sensors on board, and sends it wirelessly to the main computer some distance away. The modules are simply parts that can be replaced and are compatible with other parts. You can say that the base with the 6 wheels is also a "module".. we can replace it with a stationary stand, or even a float to traverse across water.

    The CE Bot rover is just a cut down version of a lunar robot. When Big K first announced the Google Lunar X Prize, we all got pretty excited, and thought that we can design our own lunar robot. However, it will be a more realistic project if we made a normal rover that has real life applications, such as search and rescue, as well as recon. Its very fortunate that Xheavenlyx has an old laptop that we can use as the brain.

    If CE Bot is successful, it will be a great contribution to the society ๐Ÿ˜€ We aim to make the process of creating the Bot as open as possible, so others can duplicate it for their research purposes.
  • KINETIC_JOULES
    KINETIC_JOULES
    ash
    Yes, the rover will be doing the data collecting ๐Ÿ˜€ Its going to have sensors on board, and sends it wirelessly to the main computer some distance away. The modules are simply parts that can be replaced and are compatible with other parts. You can say that the base with the 6 wheels is also a "module".. we can replace it with a stationary stand, or even a float to traverse across water.

    The CE Bot rover is just a cut down version of a lunar robot. When Big K first announced the Google Lunar X Prize, we all got pretty excited, and thought that we can design our own lunar robot. However, it will be a more realistic project if we made a normal rover that has real life applications, such as search and rescue, as well as recon. Its very fortunate that Xheavenlyx has an old laptop that we can use as the brain.

    If CE Bot is successful, it will be a great contribution to the society ๐Ÿ˜€ We aim to make the process of creating the Bot as open as possible, so others can duplicate it for their research purposes.
    ^_^ Yes, I'm aware of what modular means. Didn't you say it would have a camera? Like, maybe for detecting objects in the way. I liked the idea of the virtual map.
    I'm sorry if I'm being annoying about this. I'm just trying to get this straight about how I should sketch this out.
    (Lmao. Time to break out the compass. . . protractor. . . )
  • Ashraf HZ
    Ashraf HZ
    Yep, the camera will be the sensor for image collection. Its the most important sensor on CE Bot, since we will transmit the video (pre- or post- processed) to another computer across a wireless connection.

    Annoying? Nah, its good to keep asking questions to clarify ๐Ÿ˜€

    Have you seen the previews of the movie WALL-E? Its something like that robot, except a little more simpler, smaller and has wheels.
  • KINETIC_JOULES
    KINETIC_JOULES
    Yes. . . I saw the previews. I wanted to go see the movie.
    And ok. . . I've got so many designs to work on right now, it's not even funny.
  • raj87verma88
    raj87verma88
    You are in no pressure Tyler, just don't forget to do it or take so much time that we forget you were to do something....take your own sweet time. I know that sometimes the ideas don't come and the mind becomes blank or sometimes so many ideas come that you are unable to decide which is the best.
  • Ashraf HZ
    Ashraf HZ
    Oki doki folks, this thread will be closed. Good to see CE Bot progressing at a relatively quick pace. Thank you all for your valuable contributions ๐Ÿ˜€

    Please continue the discussions here:
    #-Link-Snipped-#

You are reading an archived discussion.

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