Let's Make Robots!


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I built this robot to test some different ideas that I had. One of them were the CD wheels and other was the free wheel tilted by a servo.

It ended up to be a crazy (maluco) robot. In full speed it could do massive drifts but was very unstable...

I decided to reduce the voltage given to the motors so it could behave how you can see on the video.

The front wheel is attached to the servo using polymorph:

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Interesting. It looks like the front wheel steers like a motorcycle. The servo seems to be oriented so that the wheel changes angle in the vertical plane, rather than rotating on the horizontal.

Are both rear wheels driven at a constant speed, or do you need to adjust the left and right motor speeds to turn? I'm assuming you run them at the same speed and allow the low friction CD wheels to slide on the nice hard floor surface.

Yes, the idea was taken from a little toy I helped my 7 years old cousin building:


I found the way it could move interesting and tried to replicate that on this robot :)


The back motors are always rotating in the same direction and speed, like if they where connected directly to the 5V and GND.

Cool. This would be a good application for one of the Tamiya gear sets that has a single motor and a shaft on each side. Seems a waste of the dual gearbox, but I'm guessing it is what you had around.

Though, I suppose having two separate motors and gear trains allows a bit more slip than if they were both on one fixed axle.

Anyway, very cool robot.

Yes, this was the only gearbox I had ready to use.