Let's Make Robots!

Differential Drive

Differencial Drive using one PWM and 4 GPIO

I want to make a differencial drive using only one PWM and 4 GPIO pins, because the motors always move in the same speed irrespective of their direction. So I have designed this H-Bridge Motor Driver, I want to make sure it works, before trying it out practically.

 

 

R1

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Wild Thumper Controller Left/Right speed way off

Hi,

i'm using a Wild Thumper controller on a DFRobot 4wd chassis and motors.
I noticed if I set a certain speed, there's a lot of difference between the left and right wheels.

But it is not consistent. The speed tends to equal out after a few seconds.

And it is dependent on the direction. e.g.: going forward starts with left going faster than right, and with going backwards it starts with right going faster than left... weird....

 The effect is worse with higher speeds...

Any ideas?

Thanks,
Patrick 

Navigate around in a room very bad,
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Ok after a loooong time not being active on this page I figured that I had to post another NXT robot. Ok, this is my first robot with a differential, so don't … Read more
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