Stiffness Optimized Multi-Robot Behavior Planning using Reduced Hessian Method

Stiffness is a critical weakness in robot-driven manufacturing. Following the idea of enhancing stiffness by physically coupling multiple robots, the cooperative behavior should be optimized. We present a reduced Hessian method to generate stiffness optimized placement and motion for coupled robots with given manufacturing processes. To improve efficiency the search space dimension of the optimization problem is reduced while the high-dimensional path and coupling constraints are satisfied in each iteration. By integrating a stiffness model in the optimization, cooperative behavior with stiffness enhancement is generated. The results are validated by experiments for both 7-axis and 6-axis robots with physical coupling.