I need somebody who knows something about electronics, specifically model radio control and automotive starter motors (and the like) to chime in.
We're thinking of building something as a moving target for our local shooting range. It would mimic the motion of a person but not move any faster than about walking speed.
What we have in mind is a couple of car batteries driving a starter motor, driving two wheels (say, the fronts off a riding mower--12" diameter max) on a small (roughly 2' x 2' square) frame. The other two wheels (the rear ones) would be the steering and probably smaller in diameter. The whole thing would be controlled by radio control (possibly something from a R/C car) with only steering and throttle. It would have to be relatively heavy (say, 100 lb max) including the batteries to remain stable and have a fairly heavy steel plate in the front and sides to protect from handgun bullet strikes, but we don't want the thing to be so heavy you can't pick it up to put it in the back of the truck. We'd use light wooden supports from which to hang cardboard targets. Optimally we'd like the ability to hook up a "disconnect" to the power if the shooter hits a critical steel plate target (center of mass, etc.)
The only wrinkle that's giving me pause is having a servo motor strong enough to steer it. Windshield wiper motor, perhaps?
Thoughts?
