Control of a hybrid pneumatic/electric motor

Pneumatic motors have many advantages over electric motors, conventionally used for robotics and automation applications. However, the control performance of pneumatic motors is quite unsatisfactory, mainly due to the compressibility of air. We have recently proposed the development of hybrid pneumatic/electric motors where a small electric motor is used in conjunction with vane-type pneumatic motors, so that the hybrid actuator has better damping and ease of control than the pneumatic motor. In the present work, we consider the switching control of the hybrid actuator system, and, propose control algorithms for position, and trajectory control of the system. The performance improvement of the new actuator is illustrated by results of experimental implementation.