Sub-time-optimal control strategies for robotic manipulators

Due to the highly nonlinear structure of the robotic equation of motion, the exact time optimal control is so far unavailable. The high speed requirement in many applications renders PID controller unsatisfactory. Therefore, it is important to seek a suboptimal control strategy that is implementable and performs better than the PID controller. Two types of such controllers are examined in this paper. We will demonstrate the reasoning behind each approach and compare their respective strengths and flaws.