Hi all,

We're working on a project which involves a cart rolling down a hill and then having a limited destance in which it must come to a standstill. After this point, it should accelerate in the opposite direction, back up the hill.

The way I proposed doing this, after looking around the web, would be to construct a time delayed circuit where both the input and output is the motor, once working as a generator and once as a motor. In this case, I think the best approach would be to allow the capacitor to charge until the input voltage is below a certain threshold and afterwards discharge is (i.e. power the motor) until the charge is below a similar threshold. However, my electronics skills aren't that brilliant, so I was wondering if you guys could help me construct a schematic.

Parts should be no problem, however simplicity is appreciated.

 

You will need auxillary power for return trip. Might use a worm gear speed reduction-motor stops- cart stops. Just simple timer, 50 % duty cycle driving DPDT reversing relay.

 

Charging and discharging a cap will work for providing a crude timing function, but not as a source of significant energy. Unless you're using huge and expensive caps. But even then, only a portion of what you need to go UP the hill will have been captured coming DOWN the hill. Sad truth of physics. But maybe that's the purpose of this exercise, to demonstrate the difficulty of efficiently capturing potential energy as electrical energy?