This thesis has presented kinematics, hardware construction, and control architecture for the planar parallel 3-RPR manipulator built at Ohio University. This three-dof manipulator is actuated by three active pneumatic cylinder prismatic joints. The revolute joints are all passive. The workspace computation and analysis have also been presented in chapter 2.
In a limited workspace the robot can reach general planar poses (translation and rotation). Applications for this type of robot include manufacturing and assembly where high speed and accuracy are required in a relatively small workspace. Other applications are planar motion simulators and haptic interfaces. The 3-RPR hardware is controlled in real-time via a PC with a Simulink model reading LVDT feedback and commanding solenoid valves via the Quanser Multi-Q boards and Wincon software. The control architecture controls the three pneumatic cylinder lengths independently but simultaneously in this environment. The coordinated Cartesian control of the 3-RPR planar parallel robot via linearized independent prismatic link length control has been implemented. The Simulink block diagram is built, based on this control architecture.
The control routine for the Cartesian control modes (inverse pose control or resolved rate control) has been proposed and can be implemented as suggested in the concluding chapter. Future work suggests hardware improvements should be made to improve accuracy. Also, workspace optimization can be done for future work.