1) The input shaft rotates an eccentric. 2) The eccentric moves the cycloidal disc in an orbit. 3) The disc's cycloidal profile successively engages the ring pins, causing the disc to rotate slowly in the opposite direction. 4) This slow rotation is picked up by the output pins/rollers and transferred to the output shaft. The ratio depends on the number of pins relative to the disc's lobes.
The need for compact, stiff and durable high-ratio, high-torque reducers that tolerate shock loads — critical in the joints of robots that carry heavy loads.
Patenting of the cycloidal drive design.
Cycloidal (RV) reducers become common in industrial robot joints.
Proprietary cycloidal actuators used in the legs of the Agility Digit 5 humanoid.
