CE Project: CE Bot [PART TWO]

Wow. . .a whole new thread! Yay!
Like I said, I'll get on those designs very soon. I will be gone later on today, Saturday, and Sunday, so no designs then. I leave at 4:00 PM my time, which is in 3 hours. Sorry I haven't come up with anything lately. . . I've got artists block. It sucks.

Take your time, Kinetic.

CEans, please do post your suggestions or comments in this thread. By posting here, you are part of the project already 😉

Just a real quick note before I forget, as we were chatting about the pros & cons of battery vs. gas power supply, how to provide drive for the bot and solar cells to recharge or linking the brakes into alternators to provide electrical charge. Personally I think awd via chain or tracks is best due to simplicity, weight savings. dwd, direct wheel drive can also be achieved though would add to weight. I'll talk more about then later.

I'm back guys!

gohmJust a real quick note before I forget, as we were chatting about the pros & cons of battery vs. gas power supply, how to provide drive for the bot and solar cells to recharge or linking the brakes into alternators to provide electrical charge. Personally I think awd via chain or tracks is best due to simplicity, weight savings. dwd, direct wheel drive can also be achieved though would add to weight. I'll talk more about then later.

Thanks for that, gohm. Looking forward to see more details later! Could you sketch how you'd implement the awd via chain?

Also, I looked into your .89 nitro idea. They are called "Glow Engines", yes? They seem to be pretty cool, hehe. What are their fuel consumption like? Would you require a large fuel tank? Lets say that the rover will operate for around 1 hr. Max speed will be 4-5 km/h. I'm not too sure of the weight.. 20 kg maybe?

Back to using DC motors, here's some plus points to consider:
1- Runs on electricity. Rover will have one common power source to power all subsystems.
2- relatively small size. Can have multiple motors to implement the "direct wheel drive". If one motor fails, the rest can continue running. Thus, redundancy is assured.
3- Easy to swap DC motors depending on how its mounted.. only need to resolder the wire connections.
4- Very accurate control via programming.
5- When rover is stationary, DC motors will not consume any electricity. Its pretty much "power on demand".

Some bad points
1- even small, a collective weight of 4 DC motors might be heavy.
2- Will consume a lot of electricity if rover is going uphill or struggle over terrain.
3- need to expand battery size and/or amount to accommodate motors.

KINETIC_JOULESI'm back guys!

Welcome back! Ok, now get back to work 😉

<a href="https://sites.google.com/a/crazyengineers.com/ce-lab-projects/CE-Bot/case-studies" target="_blank" rel="nofollow noopener noreferrer">CE-BOT Case Studies</a>

Hands down, I am in for building a rover something that is at least a tad-bit in league with any of the described rovers on the Updated Case studies page on celab.tk website (above). These are robo's from NASA or the Department of Defense.

Take your time to read about each of them. And also watch the videos. We will learn something about tracked system or the AWD and also the awesome system of all terrain wheel types. Pretty good.

I might add more to the list soon.

<a href="https://sites.google.com/a/crazyengineers.com/ce-lab-projects/CE-Bot/case-studies" target="_blank" rel="nofollow noopener noreferrer">CE-BOT Case Studies</a>

xheavenlyx<a href="https://sites.google.com/a/crazyengineers.com/ce-lab-projects/CE-Bot/case-studies" target="_blank" rel="nofollow noopener noreferrer">CE-BOT Case Studies</a>

Hands down, I am in for building a rover something that is at least a tad-bit in league with any of the described rovers on the Updated Case studies page on celab.tk website (above). These are robo's from NASA or the Department of Defense.

Take your time to read about each of them. And also watch the videos. We will learn something about tracked system or the AWD and also the awesome system of all terrain wheel types. Pretty good.

I might add more to them soon.

<a href="https://sites.google.com/a/crazyengineers.com/ce-lab-projects/CE-Bot/case-studies" target="_blank" rel="nofollow noopener noreferrer">CE-BOT Case Studies</a>

All of these with the exception of the autonomous drilling bot, are using the chain. I agree with Gohm on the use of either chains or tracks instead of individual motors for each wheel. His idea of 0.89 nitro is also quite good. It is not very bulky, quite powerful for its size, providing good speeds to RC cars in which it is used.

@Ash:- Yes they are called glow engines also as they use glow plugs instead of spark plugs to ignite the fuel. The fuel used is called glow fuel which is either methanol or nitromethane. You can refer this link for more info #-Link-Snipped-#)

From Wiki <a href="https://en.wikipedia.org/wiki/Radio-controlled_model" target="_blank" rel="nofollow noopener noreferrer">Radio Controlled Model</a>:

development of technologies like <a href="https://en.wikipedia.org/wiki/Brushless_motor" target="_blank" rel="nofollow noopener noreferrer">Brushless Motor</a> and <a href="https://en.wikipedia.org/wiki/Lithium_polymer_battery" target="_blank" rel="nofollow noopener noreferrer">Lithium Polymer Battery</a>. These allow electric motors to produce much more power rivaling that of fuel-powered engines. It is also relatively simple to increase the <a href="https://en.wikipedia.org/wiki/Torque" target="_blank" rel="nofollow noopener noreferrer">Torque - Wikipedia</a> of an electric motor at the expense of speed, while it is much less common to do so with a fuel engine, perhaps due to its roughness.

The main reason Glow engines cannot be used is because its practically impossible to control the torque (and speed in large variations). This is possible and efficient in electric motors. Plus we will be running our bots for hours and may also use solar power for longer uses, not 10 or 20 minutes as is possible with a glow engine used in RC cars.

good point XhX. It skipped my mind, so Glows are out of question

Great work, xhx! We were sorely in need of case studies 😛

The 6 wheels is a compromise between tracks and using just 4 wheels. Tracks are not good when turning, in the sense that they require lots of power to overcome turning frictions. The actual "tracks" are an added weight. 4 wheels will not provide enough traction, and can get stuck in certain gaps or humps.

We can make the turning radius pretty tight using the ackerman equation, also keeping in mind that both the front and rear wheels have steering.

One thing I notice that if you are able to control each side of the wheels separately, you can possibly execute a neutral turn like tracked vehicles.

I suppose we can use a chain for each side of the wheels, albeit they'll be inside rather than out. That would reduce the amount of dc motors to 2 😀 Of course, this assumes that we want the front and rear wheels to rotate at the same speed.

ashWelcome back! Ok, now get back to work 😉

*Salutes* Yes sir!

Good points everyone. But you know, everyone should see the videos.

First thing I noticed is the size. We have to know for sure that we are ok with and also finalizing a smaller robot like the Packbot (You should read the link before you ask whats a packbot) or have one as big as SCARAB.

As ash said, we will mostly use the 4/6 wheel config. BUT with good suspenstion system and flexibility. See second video on SCARAB (1:30 min) VERY VERY Important.

xheavenlyxGood points everyone. But you know, everyone should see the videos.

First thing I noticed is the size. We have to know for sure that we are ok with and also finalizing a smaller robot like the Packbot (You should read the link before you ask whats a packbot) or have one as big as SCARAB.

As ash said, we will mostly use the 4/6 wheel config. BUT with good suspenstion system and flexibility. See second video on SCARAB (1:30 min) VERY VERY Important.

Is there supposed to be a link?
Maybe my computer is screwed up. . .

I've got an idea.
I was working on the sketch of the robot, when I was thinking about the wheel base. What If I made the front set and the middle set farther apart than the middle set and the back set of wheels, due to momentum.
I was thinking, since this is going to be all-terrain robot, the front two sets of wheels need to be independent meaning a 4-wheel drive instead of a 6-wheel drive; and the back set will be dependent on the front two. I figured you could increase momentum and decrease power use by making it a 4-wheel drive instead of a 6-wheel drive but increase the momentum so it would go faster.
Do you know what I'm trying to say?

1.) To increase momentum:
Separate the front set and the middle set of wheels farther apart than the middle and the last set.
2.) To decrease power use:
Make the front two wheels independent, meaning only the front two sets are motorized, while the back set is dependent on the front two sets and does not require power use.
3.) To put it all together:
This increases travel while decreasing power use.

Do you get what I'm trying to say?

KINETIC_JOULESI've got an idea.
I was working on the sketch of the robot, when I was thinking about the wheel base. What If I made the front set and the middle set farther apart than the middle set and the back set of wheels, due to momentum.
I was thinking, since this is going to be all-terrain robot, the front two sets of wheels need to be independent meaning a 4-wheel drive instead of a 6-wheel drive; and the back set will be dependent on the front two. I figured you could increase momentum and decrease power use by making it a 4-wheel drive instead of a 6-wheel drive but increase the momentum so it would go faster.
Do you know what I'm trying to say?

1.) To increase momentum:
Separate the front set and the middle set of wheels farther apart than the middle and the last set.
2.) To decrease power use:
Make the front two wheels independent, meaning only the front two sets are motorized, while the back set is dependent on the front two sets and does not require power use.
3.) To put it all together:
This increases travel while decreasing power use.

Do you get what I'm trying to say?

No, I do not get it. Explain your points.

KINETIC_JOULESI've got an idea.
I was working on the sketch of the robot, when I was thinking about the wheel base. What If I made the front set and the middle set farther apart than the middle set and the back set of wheels, due to momentum.
I was thinking, since this is going to be all-terrain robot, the front two sets of wheels need to be independent meaning a 4-wheel drive instead of a 6-wheel drive; and the back set will be dependent on the front two. I figured you could increase momentum and decrease power use by making it a 4-wheel drive instead of a 6-wheel drive but increase the momentum so it would go faster.
Do you know what I'm trying to say?

1.) To increase momentum:
Separate the front set and the middle set of wheels farther apart than the middle and the last set.
2.) To decrease power use:
Make the front two wheels independent, meaning only the front two sets are motorized, while the back set is dependent on the front two sets and does not require power use.
3.) To put it all together:
This increases travel while decreasing power use.

Do you get what I'm trying to say?

Ah, you're thinking like 6 wheeled trucks yea? Actually, remember, the rear wheels can be steered too 😀

It may be 6 wheel, but we may choose to drive only the front and rear wheels. Its the middle set that is not powered (for now). It provides support for the middle section of the chassis, to avoid it from sagging in the middle, as well as some traction.

Also, its important to keep the distances equal to provide stability, stable steering (using the ackerman diagram here: #-Link-Snipped-# ), as well as the ability to drive forward and backward with the same performance.. as the rover will tend to be biased towards one direction.

The link to the Scarab video is on the #-Link-Snipped-# website 😀 Gosh, its much bigger than I thought! Simply cool.

xhx, we might need to reconsider the design a little if you want that kind of flexibility. The wheels would have to be attached separately from the chassis or something.

This is another robot we can also look at. It has 6 wheels, and a super flexible frame:
#-Link-Snipped-#

Nevermind, you guys. The thought was good in my head. I should just stick to the designing, for I am not smart enough to contribute any knowledgeable information.
So just pretend I didn't say that, and continue with the ideas.

Nevermind, you guys. The thought was good in my head. I should just stick to the designing, for I am not smart enough to contribute any knowledgeable information.
So just pretend I didn't say that, and continue with the ideas.

1. Shut up. Never say that. "I am not smart enough to contribute any knowledgeable information."

2. I read your idea. You know, Ash gave a reply. So if you still believe thats a good idea, make a design report. Try some calculations as I think you can have a point there (thats how we will move in the design process, facts from calculations), but yes we NEED to have front AND back powered. If the front two wheels are above the ground the remaining wheels have to run the BOT.

3. The link was in my earlier post: <a href="https://sites.google.com/a/crazyengineers.com/ce-lab-projects/CE-Bot/case-studies" target="_blank" rel="nofollow noopener noreferrer">CE-BOT Case Studies</a>

4. @Ash: Yea exactly! I think we should have that kind of flex. We need it. Away from the chesis and with flexible links, something like the mars rover too. A mix. We have to design it properly.

5. Ash, Raj, KINETIC. We are reaching a state where the project is going pretty fast 😀 Now we can go a bit more mathematical. For every major design suggestion we must do a math study and write a small report (if possible).

xheavenlyx1. Shut up. Never say that. "I am not smart enough to contribute any knowledgeable information."

2. I read your idea. You know, Ash gave a reply. So if you still believe thats a good idea, make a design report. Try some calculations as I think you can have a point there (thats how we will move in the design process, facts from calculations), but yes we NEED to have front AND back powered. If the front two wheels are above the ground the remaining wheels have to run the BOT.

3. The link was in my earlier post: <a href="https://sites.google.com/a/crazyengineers.com/ce-lab-projects/CE-Bot/case-studies" target="_blank" rel="nofollow noopener noreferrer">CE-BOT Case Studies</a>

4. @Ash: Yea exactly! I think we should have that kind of flex. We need it. Away from the chesis and with flexible links, something like the mars rover too. A mix. We have to design it properly.

5. Ash, Raj, KINETIC. We are reaching a state where the project is going pretty fast 😀 Now we can go a bit more mathematical. For every major design suggestion we must do a math study and write a small report (if possible).

What I'm saying is:
What I posted earlier didn't make any sense. I realize now what I said.
The sketch I'm working on now, the wheel base it basically what I have. I'm still trying to figure out everything. It's really complicated.

Oops, sorry if the post came off as rude. lol, I was being sarcastic in the point #1. After that it was just other points 😀

It's okay. No biggie! ^_^ I just got google sketch up, and as soon as I figure out how to use it, I'll be working on the digital sketch of the bot.

KINETIC_JOULESIt's okay. No biggie! ^_^ I just got google sketch up, and as soon as I figure out how to use it, I'll be working on the digital sketch of the bot.

Kinetic, don't worry about sharing ideas. To be an engineer, you have to be confident in voicing out your ideas and thoughts. We are not here to criticize your ideas with malice: rather, we are here to discuss the points!

Doesn't matter if you are right or wrong.. whatever we discuss will be valuable to all. I've typed posts that seem a little silly (even when I was sure I was right), but understood better after discussions! Thats the problem we have in college classes.. most are scared or shy to ask the lecturer questions, in case he/she makes a fool out of themselves. This is the wrong mentality 😀

So be sure to read and analyze the replies you have, and understand the different perspectives if it differs from your original ideas. I'm still an "aspiring" engineer like you (albeit with a year left), and I learn quite a lot from Crazy Engineers thanks to the rest of the CEans who contribute to the discussions 😀

Good luck with the Google SketchUp. There should be lots of tutorials online available!

xheavenlyx4. @Ash: Yea exactly! I think we should have that kind of flex. We need it. Away from the chesis and with flexible links, something like the mars rover too. A mix. We have to design it properly.

5. Ash, Raj, KINETIC. We are reaching a state where the project is going pretty fast 😀 Now we can go a bit more mathematical. For every major design suggestion we must do a math study and write a small report (if possible).

If we could embed the motors inside the wheel hubs (like the Shrimp robot), we will only need to worry about the steering mechanism. Thats the only thing thats troubling me at the moment.. because if you want the wheel to be super flexible, the motor shafts would also need to be flexible. I believe the only way to do that is to use multiple universal joints or something. Gohm and patty, can you confirm this?

Also, is the ackerman equation valid for the rover? We should start running calculations with it soon, like xheavenlyx said. I've never really fabricated it before, even with lego.. (not enough pieces).

Im sorry for my lack of wireless testing 😔 I'm actually involved in another project at uni (CANSAT). The good thing is, it has a wireless aspect using radio modems and gps.. so I can indirectly source the research from that into CE Bot. 😎

I'll try doing something with the WiFi this weekend *prays*

Thanks, ash
As for my sketching progress. . . it's basically a pile of mess.
here's the ideas so far:

#-Link-Snipped-#

#-Link-Snipped-#

#-Link-Snipped-#

KINETIC_JOULESThanks, ash
As for my sketching progress. . . it's basically a pile of mess.
here's the ideas so far:

#-Link-Snipped-#

#-Link-Snipped-#

#-Link-Snipped-#

Good work, Kinetic! Much better than my first attempt in Google SketchUp 😛

Can you this time make the axle angular like a triangle. Something like this, from the front view:

   
   _
  / \
 0   0

Where the "0"'s are the wheels. Hope you understand! Check out the Shrimp robot link to see what I'm hinting at. It'll be interesting to see what it'll look like!

Like. . .I'm not getting it. The axle is supposed to be shaped like that?

Its an additional idea, a modification of the original lego design. You know when you stand up with your feet far apart? You legs are sorta angled. Imagine your shoes as the wheels.. something like that, haha.

Kinda like what I've already got?

Yes, you are correct on the joint idea ASh.

ashKinetic, don't worry about sharing ideas. To be an engineer, you have to be confident in voicing out your ideas and thoughts. We are not here to criticize your ideas with malice: rather, we are here to discuss the points!

Doesn't matter if you are right or wrong.. whatever we discuss will be valuable to all. I've typed posts that seem a little silly (even when I was sure I was right), but understood better after discussions! Thats the problem we have in college classes.. most are scared or shy to ask the lecturer questions, in case he/she makes a fool out of themselves. This is the wrong mentality 😀

So be sure to read and analyze the replies you have, and understand the different perspectives if it differs from your original ideas. I'm still an "aspiring" engineer like you (albeit with a year left), and I learn quite a lot from Crazy Engineers thanks to the rest of the CEans who contribute to the discussions 😀

Good luck with the Google SketchUp. There should be lots of tutorials online available!



If we could embed the motors inside the wheel hubs (like the Shrimp robot), we will only need to worry about the steering mechanism. Thats the only thing thats troubling me at the moment.. because if you want the wheel to be super flexible, the motor shafts would also need to be flexible. I believe the only way to do that is to use multiple universal joints or something. Gohm and patty, can you confirm thi

Also, is the ackerman equation valid for the rover? We should start running calculations with it soon, like xheavenlyx said. I've never really fabricated it before, even with lego.. (not enough pieces).

Im sorry for my lack of wireless testing 😔 I'm actually involved in another project at uni (CANSAT). The good thing is, it has a wireless aspect using radio modems and gps.. so I can indirectly source the research from that into CE Bot. 😎

I'll try doing something with the WiFi this weekend *prays*

Here's more mess:
#-Link-Snipped-#
#-Link-Snipped-#
#-Link-Snipped-#
#-Link-Snipped-#
#-Link-Snipped-#

Excellent work KINETIC! I loved the last design (#8) But I think dont spend a lot of time on that rite now, keep doing it side by side. There is something important that you will have to do in some time.

I will post what it is soon. And its very important 😀

Thanks! It's basically how I progressed. They're in order. I'm glad you like it! And so, what you're saying is just wait and don't work on the design right now? You have something in mind?

READ THIS POST CAREFULLY. IMPORTANT!




Ok, I have a proposal.

Before we start finalizing the chassis design, we need to know what the chassis will be holding. Its like building a foundation without knowing if the building is a high-rise or a storeroom!

Plus we will also know the power requirment and the total weight of payload.

===========================================

So our next task is SENSORS:

1. Find the properties for each sensor type. Main points like Input method and Output method. (see example at end)

2. Find various alternatives or vendor specific devices.

3. Datasheet for each sensor or specifications from website.

4. Lastly, why you think we should use the specified sensor (optional).

===EXAMPLE===

1. Video Camera: "Various properties..." then Input: HW:USB, SW:<instructions>. Output: HW: USB, SW: ideodata, <instructions>

2. There are many cameras so we can see the cheapest and most flexible one, like with more range of operating resolution 300x600 to 1270x700). (This is just an example).

3. Find datasheet or if not then specifications from product website.

4. "This perticular model has ... this ... and thats why we should use it...blah blah".

===END EXAMPLE===

So tell me who wants to take which sensors. If there is an overlap we will look at that and deside by tommorow.

The research must finish within a week. 😀 The final report will be after that.

I'm still concerned about the body design. . . and do you mind if I experiment with the sensors later?

Xhx, a week? 😛

Thats a great diagram you drew. Things are more organized now!

I'll take the camera. I've already done some research on it for my CANSAT project. We have two options.. either we hack an existing webcam, or we fabricate our own camera using CCD imagers. At the moment, a webcam hack is doable because you'll connect it directly to the laptop through USB. No need to worry about decoding the USB signals 😉

I propose this webcam:
Philips SPC900NC
CCD sensor: Sony ICX098BQ
Resolution: 640X 480
Pixels: 300K
Pixel size: 5.6 micron

We can mount a better lens on the existing one for better image quality, as well as put it on servos so it can rotate in the x-y axi. If possible, we can also make a mechanism to automatically change the image filters, so we could switch from normal to infrared views 😉

I'll upload other webcams and the datasheets of their CCD sensors on CE Lab tomorrow or the day after.

I might as well take the light sensors as well, unless someone else wants its.

@ Kinetic
Keep up the good work! By the way, the word "censor" is almost an antonym of "sensor" if you think about it 😉 Don't confuse the two!

What are the expected weights and sizes of the equipments that will be fit on the robot. I mean other than the drive train and chases.

ash@ Kinetic
Keep up the good work! By the way, the word "censor" is almost an antonym of "sensor" if you think about it 😉 Don't confuse the two!

Sorry. That was an accident!

I gave an estimation of 20Kg before, but that was a number I pulled out of thin air (sorta). Sensors are quite negligible in size and weight compared to other subsystems. The heaviest stuff would probably be the batteries, motors, wheels, laptop as well as additional actuators such as grippers.

At the beginning, the max footprint that I proposed was the size of a standard magazine. Perhaps we should extend that to around A3 size (just the body).. it looks enough for our purposes.

We could certainly find out these weights in our research stuff, if one takes the time to do it though 😔

Did you happen to see that I made a place for the lap top in my design. That's just where it's supposed to sit. ^_^ what do ya think?

I was just thinking, that we need to have an approximate idea of the total weight that the chases and wheels will support. It would help in the designing and fabrication of these parts. It would also help in the stress calculation and other equivalent stuff.

@Raj

I was just thinking, that we need to have an approximate idea of the total weight that the chases and wheels will support. It would help in the designing and fabrication of these parts. It would also help in the stress calculation and other equivalent stuff.

Thats what I said we have to do. Its the most important thing, and it IS NOT EASY!

@Kinetic

Ok, I will need some time to think of this. If you are interested to do the chasis rite now. Then I want you to read about the rocker-bogie design and incorporate in your present idea. Here are links:

WIKI: <a href="https://en.wikipedia.org/wiki/Rocker-bogie" target="_blank" rel="nofollow noopener noreferrer">Rocker Bogie</a>
PDF: #-Link-Snipped-#

@Ash.

Ash, please, I am going crazy here. I need to know what the robot will be used for and in which environment. Again, its like building a house without knowing if we need a slant roof for snow or a cement house for tropics.

IF robot is used to mapping in deserts THEN it has to be a bit bigger, more than 20 KG and that will depend on Sensors, environment and abilities.

IF Robot is used in forest areas for trespassing violations (Border security, airport security) then it has to be long lasting, sturdy and weather proof. Everything changes.

And so on...

Ash, you know I was confused before too. So are we SURE we will be going with Remote Sensing, Mapping robot? For laaaaarge areas and weather intensive, can survive for days using solar power and GPS (I have a GPS module that can be sacrificed)? Wont that be a good project? We already have 15 year old's building useless sensor bots...too comon. We need a something that can SURVIVE! 😀 What do you think of this idea?

Hi guys!

After a long time, huh? I remember promising to do the block diagram and then left, couldnt help it.

I was going through all the posts of CE:Bot and this CE:Bot 2. And whoa you people have done a load of good job (and I feel that everyone here is smitten by the drive system 😉).

Anyways, going into the topic, my knowledge(the areas where I can help) includes Sensors, Processor(s), Drive System, Power Supply Unit(s) and Communications.
But of these I personall dislike the last two(Power Supply Unit(s) and Communications), which leaves me with three topics.

1. Sensors - I dont have practical access to any of the sensors mentioned, but I do have a good knowledge and a very good googling capability. Which means I will not be able to provide the exact details of how each thing works, but can help you guys in searching for the datasheets, and any other information you want.

2. Ah, I feel at home when discussing them. My true love, programming *blush*. I remember reading somewhere in the discussion regarding the language to be used, Python (and was Ruby also discussed?). Why? Firstly, Do they have compilers for RTOS, linux and PIC/ATMEL? I dont think so. Secondly, Do they support assembly langauge instructions. Again, I dont think so. Third, Do they support low level instructions? Again, I dont think so. Then why python? The only language that can be effectively used in this case is C/C++. And regarding the use of either PIC or ATMEL, both are good, anyone of them can be used. I think ATMEL is easier and powerful to work with. My suggestion is to use each PIC/ATMEL for each module (like for the drive sstem, one powerful micro-controller, for each sensor, smaller micro-controllers for which the requirement of RAM, ports, etc... is not much).
I'll divulge in detail when the turn comes (Maybe xhx will get angry at me for discusing processors when the current turn was for sensors).

3. I think ash's idea of indepently powered wheels is very good, which gives u an excellent control, flexiblity, durability, and easy to program.

I think its enough for now, the post size is getting longer and I am getting sleepier :sleepy:.

Waiting for comments...

xheavenlyx@Ash.

Ash, please, I am going crazy here. I need to know what the robot will be used for and in which environment. Again, its like building a house without knowing if we need a slant roof for snow or a cement house for tropics.

IF robot is used to mapping in deserts THEN it has to be a bit bigger, more than 20 KG and that will depend on Sensors, environment and abilities.

IF Robot is used in forest areas for trespassing violations (Border security, airport security) then it has to be long lasting, sturdy and weather proof. Everything changes.

And so on...

Ash, you know I was confused before too. So are we SURE we will be going with Remote Sensing, Mapping robot? For laaaaarge areas and weather intensive, can survive for days using solar power and GPS (I have a GPS module that can be sacrificed)? Wont that be a good project? We already have 15 year old's building useless sensor bots...too comon. We need a something that can SURVIVE! 😀 What do you think of this idea?

My good friend, we have to realise that this is our first prototype! Haha.. for sure, no robot design is perfect on the first try. We need to start small, then scale up. Remember, our robot is designed to be modular, so we can always enlarge the size later. We need to focus on the functionality first, rather on reliability and survivability. Once we score on the sensors, communications and movement over rough terrain, we would have completed our first objectives. So indeed, we are still doing a remote sensing and mapping robot, but we dont need highly sophisticated robot to do that yet.

After we know they work, we can start focusing on secondary objectives. We never really discussed about long term survivability until recently. I gave an estimate of 1 hr when we first started, which is long enough to collect some sort of data. If we manage that, then we can move on to install solar panels and other added enchancements. The fact that we are using your laptop means it provides is with flexibility on configurations. At least we do not have to fabricate that many new PCB's 😀

bayazidahmed1. Sensors - I dont have practical access to any of the sensors mentioned, but I do have a good knowledge and a very good googling capability. Which means I will not be able to provide the exact details of how each thing works, but can help you guys in searching for the datasheets, and any other information you want.

2. Ah, I feel at home when discussing them. My true love, programming *blush*. I remember reading somewhere in the discussion regarding the language to be used, Python (and was Ruby also discussed?). Why? Firstly, Do they have compilers for RTOS, linux and PIC/ATMEL? I dont think so. Secondly, Do they support assembly langauge instructions. Again, I dont think so. Third, Do they support low level instructions? Again, I dont think so. Then why python? The only language that can be effectively used in this case is C/C++. And regarding the use of either PIC or ATMEL, both are good, anyone of them can be used. I think ATMEL is easier and powerful to work with. My suggestion is to use each PIC/ATMEL for each module (like for the drive sstem, one powerful micro-controller, for each sensor, smaller micro-controllers for which the requirement of RAM, ports, etc... is not much).
I'll divulge in detail when the turn comes (Maybe xhx will get angry at me for discusing processors when the current turn was for sensors).

Welcome back, again 😛 Actually, we will still be using other languages. The beauty of Python is that it can work well with C/C++, or other langs. We use Python for high level non-critical tasks in the laptop itself. Python gives us a lot of ease and flexibility, and allows us to change code faster if we need to. It is also portable.. works in any platform (yes, it can run in Linux!). For critical processes, we will stick to ASM and C/C++. Though, xhx knows more about its application in CE Bot than I do 😛

Have you given Python a try? its quite awesome..
<a href="https://www.python.org/" target="_blank" rel="nofollow noopener noreferrer">Welcome to Python.org</a>

Heres a link to applications of python in robotics:
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For sure we will use a uC for each module. Its just that they are all interfaced together to the laptop (along with data & image processing stuff). The laptop also acts as the interface between the modules and the computer host (since we may choose to use remote control).

3. I think ash's idea of indepently powered wheels is very good, which gives u an excellent control, flexiblity, durability, and easy to program.

I think its enough for now, the post size is getting longer and I am getting sleepier :sleepy:.

Waiting for comments...

Yeah, xhx's Rocker-bogie idea works well with the independent motors. Though, we'll have a nightmarish time figuring out how to supply enough power to them 😛

xheavenlyxWe already have 15 year old's building useless sensor bots...too comon. We need a something that can SURVIVE! 😀

I was just going by what y'all were saying. Not like it's entirely my fault. I'm designing what you say to design. And they were just experiments anyway. I could always do something different. That's all you have to say. I'm not going to be immature and say I quit the team, because that doesn't solve anything, but I want to feel like I'm doing something important and productive, and not do something in vein for you to just laugh at. If it's useless. . . why didn't you tell me that to begin with? Why didn't you say do something different? If what I'm trying to contribute is useless. . . what's the point of having me around?

KINETIC_JOULESI was just going by what y'all were saying. Not like it's entirely my fault. I'm designing what you say to design. And they were just experiments anyway. I could always do something different. That's all you have to say. I'm not going to be immature and say I quit the team, because that doesn't solve anything, but I want to feel like I'm doing something important and productive, and not do something in vein for you to just laugh at. If it's useless. . . why didn't you tell me that to begin with? Why didn't you say do something different? If what I'm trying to contribute is useless. . . what's the point of having me around?

You know, that was an innocent mistake. I dont think xhx knew you are 15.. what a horrible coincidence.

Chill, Tyler. He meant amateur robots that have no real objectives and profound benefits to society, thats all. Your designs have nothing to do with his statements. I'll bet you that the next time he logs in, he'll be apologizing his heart out for the misunderstanding 😉

Carry on with it. Seriously.. your designs are kick ass. Here's a lego design with some changes made. The red objects are the DC motors, and the blue the suspension. I have no idea what steering method works with this configuration.. maybe independent servos? Thats pushing our luck, though.
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ashYou know, that was an innocent mistake. I dont think xhx knew you are 15.. what a horrible coincidence.

Chill, Tyler. He meant amateur robots that have no real objectives and profound benefits to society, thats all. Your designs have nothing to do with his statements. I'll bet you that the next time he logs in, he'll be apologizing his heart out for the misunderstanding 😉

I'm sorry. . . I'm just stressed. *tears* I didn't mean to sound like that. Forgive me?
And the design is GREAT! Really good job! That's what I thought you were talking about with the axles. . . but it was too late to change it in sketch up.

*thumbs up* its cool

I want to try doing the Rocker-bogie design that xhx suggested on MLCAD. The good thing is I can colour-code lego components, so its easy to see which subsystems is what. If someone has enough lego pieces (as well as the electric stuff), they can construct a mini model of CE Bot in real life!

ash*thumbs up* its cool

I want to try doing the Rocker-bogie design that xhx suggested on MLCAD. The good thing is I can colour-code lego components, so its easy to see which subsystems is what. If someone has enough lego pieces (as well as the electric stuff), they can construct a mini model of CE Bot in real life!

That would be cool! I don't own any legos anymore. . . I lost them years ago. *thinks for a minute* wait! Yes I do!

Ash, I would only share a servo for both sets of steering. Simple, more reliable and less weight. You'll only need to trim one servo that way.

@ Ash: A good design buddy. Let me see, You have a rack and pinion on both sides. Just wondering, why the middle set of wheels do not have those spring shockers. From your designs it seems that you want the bot chases in the lines of a Baja or dune buggy. That is a good idea, but we can try others too and settle for the one which is best.

@ Tyler: Wow, quite a big misunderstanding between two team members. I know that Ash has already calmed you but I have to say something. Tell me has anyone ever said that you are unimportant to the team or to CE in general. Have we not encouraged you in your designs. We know you are not an engineer and at the age of 15 we don not expect you to have the knowledge and experience of one. That is why you were given the job of designing. Frankly speaking, your designs are good but when we start fabricating the bot we will have to make a few or more modifications on your designs because we will have to consider the forces and calculate stuff and other things. And as the bot completes you will gain a lot of knowledge and experience. You are so lucky that you will gain such an experience at 15 while we in our 20s. I wish I was your age. In the end I apologize on behalf of CE and all its members if in any way you have been wronged. You are going to join an engineering school in the future and it is our duty to answer your queries so that when you join a univ. you will be ahead of your mates. This is the idea of CE, to help and support each other and have co-operation among ourselves.

gohmAsh, I would only share a servo for both sets of steering. Simple, more reliable and less weight. You'll only need to trim one servo that way.

You are right, gohm. Other than the points you mentioned, we also wouldn't need to worry about the steering synchronizing with each other properly if they share the same servo. The biggest problem I see is that we need a long shaft down the middle of the bot:

0-----0
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0-----0
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It'll take up valuable space. Either we rid of it entirely and use 2 servos.. or, perhaps we can offset it to the side, and use some gears to mesh the shaft with the pinions at both ends:

0-----0
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0-----0
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0-----0

I hope the "text art" is understandable. A little lazy to open a graphics program 😛

raj87verma88@ Ash: A good design buddy. Let me see, You have a rack and pinion on both sides. Just wondering, why the middle set of wheels do not have those spring shockers. From your designs it seems that you want the bot chases in the lines of a Baja or dune buggy. That is a good idea, but we can try others too and settle for the one which is best.

Thanks! Ah yes, I should have put the springs in the middle too! Haha. Still need to work on it. The support will surely disintegrate easily due to the mass of the motors too. Try out MLCAD, Patty. Its pretty fun! Just takes a while getting used to positioning the lego components. The "springs" are generated.. you'll only need to input some parameters.

Theres some interesting Lego buggy designs we can take a look at, along with their construction guide so we could see their "insides". Will try to find them later.

And Yep, we'll certainly try other designs. We sorely need a "tracked" version for comparison.