This performance is achieved in a compact design using a patented “S” tooth harmonic drive gear coupled to a DC brushless pancake motor with integral electronic commutation and a high resolution encoder. Max torque up to 7300 in-lb and positional accuracy better than 1 arc-minute can be achieved. The FHA Series is available in four frame sizes, ranging from 128 to 230mm in diameter, and 78 to 127mm length.