6 DOF Parallel Manipulator Driven by Pneumatics

摘要

The paper presents the design of a pneumatic-driven 6 degree of freedom parallel manipulator (Stewart platform), which focuses on the differences in mechanical structure parameters and control strategy design between pneumatic-driven and hydraulic-driven Stewart platforms.To meet the demands of remote control, a distributed computer control system based on CAN bus is built. The friction model and its parameters are obtained experimentally and the external disturbance force is achieved by a disturbance observer. The control algorithm combines a PD controller with the disturbance feedback and friction feedforward compensations in order to overcome the weakness of pneumatic-driven system and achieve better dynamic characteristics. Experiments verify the better trajectory performances of the parallel manipulator.