Simultaneous optimization of a two-link flexible robot arm

Integrated structure control design of a two-link flexible robot arm is investigated in this article. The whole arm consists of two flexible links, a fixed joint, a moving joint, and a tip load. The arm is driven by the torque motors at the two joints to reach predefined tip positions and to suppress residual flexural vibrations. The links of the arm are modeled using the finite element method and the cross-sectional dimensions of the beam elements are used as structural design variables. A sliding mode controller and a linear stabilizer are used to regulate the arm position. The structural and the control parameters of the whole arm system are optimized simultaneously using a genetic algorithm and the performance is compared with that of an arm with uniform links and an optimized control system. The simulation result shows that faster regulation and less weight of the arm system can be achieved by simultaneous optimization. 2001 John Wiley & Sons, Inc.