Build a sturdy box. Build in the motor.
Add a hand to hold the ball.
A lift arm rotates against the upright.
Gearing down 1 to 5 is needed for strength.
Top
40 tooth gear position is not vertical.
Rubber band springs the arm quickly forward when the lift arm is rotated.
Note: only one direction works. Do not rotate against the bottom
first. It is hard on the motor to stall.
Finished
Bounce
Ball