Patent ID: 7722494

Claim:
A method for providing a compact rotary actuation torque within a larger system, comprising the steps of: operating a cross-roller bearing as a structural joint in the larger system; rigidly interfacing the larger system using an outer attachment shell and generating a controllable elector magnetic field using a motor stator while interfacing said cross-roller bearing using an internal bull gear and providing stiffness using said outer attachment shell; containing an internal ring gear and supporting a plurality of drive shaft bearings within an output attachment plate, rigidly interfacing said output attachment plate using said internal ring gear, positioning said output attachment plate within said outer attachment shell using said cross-roller bearing; holding a prime mover rotor and an eccentric using a drive shaft and associating with said output attachment plate via said plurality of drive shaft bearings, and further rotating said prime mover rotor in response to said controllable electromagnetic field; associating said eccentric with a gear train comprising a meshing gear, wherein said meshing gear further comprises a plurality of external gear teeth comprising circular arc surface and meshing said internal bull gear and said internal ring gear along said circular arc surfaces and walking a minimal number of said plurality of external gear teeth for each rotation of said prime mover rotor, and further providing a self-contained integrated actuation torque from said prime mover rotor through said gear train along a shortest-possible transmission path including said cross-roller bearing, said outer attachment shell, said drive shaft, and said meshing gear train cooperating.