Patent ID: 7798050

Claim:
A drive mechanism adapted to be mounted on a support for controllably moving a first output shaft about either or both of two orthogonal axes, said drive mechanism having a stationary portion adapted to be mounted on said support and having a movable portion mounted for movement relative to said stationary portion, said drive mechanism comprising: a first power train for controllably rotating a first gear; a second power train for controllably rotating a second gear; and a third gear connected to said first output shaft and meshing with at least one of said first and second gears; and wherein said first, second and third gears form a portion of a differential-like mechanism mechanically coupling said first and second power trains to said first output shaft such that said power trains may be selectively and simultaneously operated so that the rotational movements of said first and second gears may be combined to cause movement of said first output shaft about either or both of said axes; whereby said first output shaft may be moved to a desired position relative to said support.