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Q8uwait
Q8uwait • Apr 6, 2008

how to slow down an electrical rc car motor ??

Hello,

i am doing a voice activated voice control.

i have an rc car .. i would like to know how can i decrease the speed on the motor ,, cause the response i have with the voice circuit is slow.. and the car is way fast..

thanks
Hi!!,buddy you better use a gear system,or set the speed such that it will increase/decrease in synchronisation with ur voice
eccentronix
eccentronix • Apr 13, 2008
how are you controlling the wheels? PWM?
desijays
desijays • Apr 18, 2008
Q8uwait
Hello,

i am doing a voice activated voice control.

i have an rc car .. i would like to know how can i decrease the speed on the motor ,, cause the response i have with the voice circuit is slow.. and the car is way fast..

thanks
Let me get this straight. You're trying to control the speed of you're motor using you're voice.

I take it that you are try to give english commands to the voice detecting circuit which will pass that info to the controller which in turn controls the motor. Well, Im not sure what kind of voice commands you are using.

But if you want to control a motor, PWM is the way to go as the poster above has mentioned.
sanih
sanih • May 2, 2008
pwm is better.
you can slow down it with pulses for example :
2/3 high 1/3 down.
xheavenlyx
xheavenlyx • May 6, 2008
can you control a normal DC motor with PWM? can u post a rough crkt idea here?

555? or a dedicated PWM generator has to be used?

I am soo weak on the motor front and its so important as a hobby!
Ashraf HZ
Ashraf HZ • May 6, 2008
I believe a 555 timer can be used, but an easy way would be using a microcontroller with a PWM output, via a motor driver 😀 Response time is pretty good.

Of course, if you want to decrease the motor speed indefinitely, using gears (plastic, for an RC car) would suffice 😉 Its a bad idea to decrease voltage to the motor directly as they have a minimum operating voltage.
arunbasillal
arunbasillal • Jul 6, 2008
add a pot to the circuit and adjust the speed to your wish.
Its that simple..
xheavenlyx
xheavenlyx • Jul 7, 2008
Yea but a Pot reduces the Voltage which reduces the speed (and also reducing the current) and then the torque gets screwed; also, you loose a LOT of power which is hell if you are on a battery. I had read somewhere about the H-bridge but never got around implementing it (and forgot if it has variable speed).

till now, on forums, H-bridge is the most used, but dont know much about it. Anyone?
arunbasillal
arunbasillal • Jul 8, 2008
Yep. Pot is a simple approach. it just creates wastage of power, but the thing gets done.
can anyone tell me what a H-Bridge is..?
Ashraf HZ
Ashraf HZ • Jul 8, 2008
I believe the waste of power might factor in too much, because the RC car runs on batteries 😉

H bridges are effectively used to control the direction of the motor rotation. There is no "fixed" design, though.

I recommend you use motor drivers (like the simple L293), and use the PWM (Pulse Width Modulation) as the input to control the speed. The PWM can be generated by a microcontroller.
gohm
gohm • Jul 8, 2008
Does your RC car currently have an esc?
arunkumarr
arunkumarr • Jun 26, 2009
Check this site for details description of DC Motor control

Arunkumar R - DC Motors
adam402
adam402 • Sep 27, 2012
is sanih said that you can slow down it with pulses for example :
2/3 high 1/3 down. where from you get it . now i am using Ghost 1/18 Scale Electric RC Truggy 2.4GHz. this Ghost
rc bilr
is a lot of fun and an excellent choice for both beginners to the RC hobby and also to experienced racers to add to their collection. but i am interested in yours. can you share where from you get it. .
grsalvi
grsalvi • Sep 29, 2012
using h-bridge of semiconductor switches which switch efficiently.
You can control how much power goes to motor by controlling switching on-off of semiconductor switches,which is done by controlling their firing pulses.(done by microcontroller)

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