Delta Parallel Robotic Manipulator Tracking Control using Fractional Order Controllers

Abstract

Tracking control of robotic manipulators presents many challenges during the controller design due to the system nonlinear behavior. This paper presents the design of a tracking control for a parallel robotic manipulator using a fractional order PID controller with the feedback linearization technique. The kinematic and dynamic models of the manipulator are obtained, and a parametric identification of the dynamic model is performed using the recursive least squares algorithms. A MSC-ADAMS/MATLAB co-simulation model of the manipulator is built to perform the control and identification tasks. The computed torque control technique based on the feedback linearization gives a linearized model of the system, which is employed to design the fractional order PID controller. The proposed controller is contrasted with an integer order PID controller with the feedback linearization technique, and both controllers are tested for tracking tasks.  Quantitative performance analysis of the employed controllers is made calculating the performance indices for each controller. Obtained results show that the fractional order PID controller has a better performance on tracking tasks than the integer order PID controller.