Modeling and force control of membrane pneumatic actuators

Research and development in the robotics of rehab and power assistance have recently focused on pneumatically driven robots. This is because of their low cost, light weight, and a simple design. We are able to build safe and flexible drives. We took particular note of a Mckibben pneumatic actuator as a drive mechanism for pneumatically driven robots. We developed a low-pressure, low-volume pneumatic actuator in previous studies. However, the generative force of these actuators is small, when you use a equipment like that used for rehab assistance. We originally developed membrane pneumatic actuators to solve this problem. A five-fingered robot hand was developed, that imitated a human´s right hand with membrane pneumatic actuators. First, we present the characteristics of a pneumatic actuator from our experiment. Then, we constructed a model using results from another experiment in a one-link arm with membrane pneumatic actuators. Next, a PI-D control system was constructed, and its gains were determined by simulation. Then, we tried to control the pressing force of a one-link arm with the controllers we constructed. As a result, we could control the pressing force with the constructed PI-D controllers.