Hello Guys, I'm building a vertical wave machine. I have a big bearing  (more like an eccentric) which is rotating by an electric motor with a constant speed of 0.359 rad/sec. When 3/4 of the bearing touches bearing  it supposed to rotate it a 1/4 turn, which as a result the ladder with the rods should rotate 1/4 turn. Once they are not touching each other (passing the green diameter), bearing  returns to its place a due to the spring resistance force and creates wave movement in the statue. I know the following parameters: In order to to remove the rods from equilibrium I need torque of 30 Nm. The motor output is 110 Nm and it rotate bearing  in constant speed of 0.359 rad/sec. The spring have resistance force of 10N Diameter of bearing  is 100 mm. I need help in calculating the green line = the contact line= the big diameter of bearing . If necessary I will be happy to provide additional data and info. Thanks to all helpers.