I am an MA sculpture student. i want to put motion into a piece i am working on. It involves a 7x7x60 cm solid wooden curve thats made of pine and wood glue in a ply-like style. Its curve means that either ends are aprox 40cm from the ground. I would idealy like to display the peice on the studio floor. I want to cause a rocking motion in it, but make it so the locomotive is unseen, inside the curved beam, perhaps in a dug out hollow. Therefor it needs to be battery powered. My tutor has surgested to me to use a small motor to power an egg shapped disc to rotate, tipping the beam into a rocking motion every time the tip of the egg shape touches the ground. Is this a good solution, and what componants would i need to create such a circuit? Any help on the subject would be hugely appriciated, i'm currently studying in Paris and dont speak french well enough to relay my concept to anyone helpfull. I just added photos of the peice so for, hope this helps.