Control design for a mixed rotary and linear motors based manipulator

Modeling and control design for a six degree-of-freedom (DOF) platform manipulator is presented. The platform is setup by three extensible legs sliding on three linear slideways (forming the base platform) each actuated by a synchronous linear servo motor. The vertical legs are actuated by inductive AC servo motors. Combination of linear and AC servo motors contribute high-speed performance of the platform. Inverse kinematics describing the platform motion is derived. With regard to the control system, two types of controllers for motors (linear and AC servo motors) and platform are designed respectively. The controller proposed consists of two parts, one is a state feedback component, and the other one uses a learning feedback component constituted by a wavelet neural network. For platform motion control, a cerebellar model arithmetic controller is adopted to control the position and orientation of the moving platform. Extensive simulation studies are presented to verify effectiveness of the control strategy on the motors and the overall platform motion.