Self balancing Botguy

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Botsmaker
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The CBC v2 computer has PID motor control and accelerometer. Has anyone tried building a self- balancing robot that drives on only two wheels, just like Botguy?

Bill Sherman

Adam
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That would be very difficult.

Botsmaker
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Its been done using the RCX and light sensors. Substitute the light sensors with the accelerometer. Here is a link to Legway: http://www.generation5.org/content/2004/legway.asp

Bill Sherman

PiPeep
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Calling the accelerometer and setting motor speed (which are both on/controlled by the CBOB) each take a few milliseconds, so I doubt you could get the refresh rate needed for something like that.

Jake_Hall
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I actually designed one a few years back using the XBC and a few Tophat sensors. It worked pretty well. Also got it to almost work with sonce Ultrasonic sensors.

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brendan
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I think a bot like this would be too unstable and therefore too unpredictable so although it might be possible, it is unlikely there is a practical situation for such a robot.

hh

Jeremy Rand
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I don't know that the accelerometer would work for this... I imagine that the tilt readings would get pretty noisy due to the vibration inherent in self-balancing. If you have gyros it might be doable. It would be a quite cool topic for a GCER paper.

Also, a CBOB operation takes 6ms. So since you want to read sensors and write motor speeds, you would get 12ms per operation, or 83Hz. The bigger problem is that the Linux kernel might pause your program for much longer than that. I wouldn't attempt self-balancing with a Linux kernel. If you loaded a custom CBOB firmware, these delays would be eliminated. Again, this would be a very good topic for a GCER paper.

-Jeremy Rand
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mmedvede
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We have built a self-balancing robot using CBC controller, but had to use an additional gyro. We used LPR510AL (http://www.pololu.com/catalog/product/1266)