Kevin A. Benedict wrote:
>
> Hi Everyone,
> I am trying to hack a Radio Control Truck to use as a robot platform.
> The truck is the Hacksaw from RadioShack, part # 60-4291.
> The front steering is done by a DC motor (FC-130RA-1224), it is in a gearbox,
>
> that turns the front wheels left or right, when the control is pushed left
> or right. It holds the wheels left or right until the control is released.
> !!!It then re-centers the wheels.!!! I am not sure how the re-centering is controlled.
> The motor has a pwr and grnd and four other wires that DO NOT
> CONNECT to the motor. The four wires go to a disk in the gear casing. Is anyone
> familiar with how this is done or what kind of controls signals it would take
> to emulate this function with a pic. I can not find a schematic of the circuit
> anywhere, to me it looks like an H-Bridge, but it is definately not a uni-polar

The centreing is probably controlled by a simple
wiper/track rotary switch. You should just be able
to a \dd a couple of h-bridges and connect the
rotary switch to some PIC inputs. :o)
-Roman

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