Kohei Hori

A direct-drive pneumatic stepping motor for robots: designs for pipe-inspection microrobots and for human-care robots

A direct-drive stepping motor based on a new principle is reported. The features of the motor include: 1) high torque (4-20 times higher than that of the same-sized conventional electric motors); 2) high stepping resolution; 3) light weight; and 4) simple structure. The motors are suitable for robots in new applications such as microrobots and human-care robots. The mechanism and theoretical analysis for the motor are presented. Two models, which are designed for pipe-inspection microrobots and for human-care robots are shown respectively.

A Study of Pneumatic Wobble Motors.

A new type of pneumatic stepping motor, named pneumatic wobble motor was developed. Pneumatic wobble motor consists of a donut-shaped wobble generator, which is made of silicone rubber, a wobble ring, which is made of metal, and a rotor. The rotor is encased in the wobble ring, which is covered by the wobble generator. The wobble generator has six chambers and injecting air into each sequentially exerted on the wobble ring, causing its revolution, which makes the rotor to rotate. In this report, first, the driving principle and design of this motor are presented. Next, its characteristics are analyzed theoretically. Two prototypes with different designs are fabricated and tested. Experimental results are very promising. The features of pneumatic wobble motor are (1) big torque, (2) simple structure, and (3) water-and dust-proof.