Edge control in precision robotic polishing based on space-variant deconvolution

In the ultra-precision manufacturing of large optical surfaces, industrial robots with small tools have the potential to become an intelligent and economical choice of surface polishing. But one of the most challenging problems is the severe edge roll-off error caused by the small tools. In this paper, an effective method is proposed to reduce the edge error in the polishing of large mirrors. The convergence rate of the form quality can be improved by adjusting the polishing removal amount. A generic space-variant deconvolution algorithm is developed to precisely calculate the dwell time. Experiments are conducted using an industrial robotic polisher and the edge roll-off error is effectively suppressed. As a consequence the polishing accuracy and efficiency of the robotic polishing technology can be improved significantly.