Concurrent Design Optimization of Mechanical Structure and Control for High Speed Robots

A concurrent design method of mechanical structure and control is developed for two-link high speed robots. An integrated design approach to achieve high speed positioning is explored, in which comprehensive design parameters describing arm link geometry, actuator locations, and feedback gains are optimized with respect to the settling time of the system. First, a two-link, nonrigid arm is analyzed and a simple dynamic model representing rapid positioning processes is obtained. Optimal feedback gains minimizing the settling time are obtained as functions of structural parameters involved in the dynamic model. The structural parameters are then optimized using a nonlinear programming technique in order to obtain an overall optimal performance. Based on the optimal design, a prototype high speed robot is built and tested. The resultant arm design shows an outstanding performance, which is otherwise unattainable if the structure and control are designed separately.