Control Method of Constant Force Grinding based on Active and Passive Control

摘要

In recent years, bone cutting tool-ultrasound osteotome has been used in the treatment of spinal stenosis. However, the contact force has a great influence on its cutting performance. The cutting speed will be reduced, if the connecting force is too small or too excessive. At present, the clamping devices at the end of the surgical auxiliary robot are mostly rigid connections, which will lead to the instability of the contact force between the surgical instruments and the vertebrae and the inability to achieve efficient and safe grinding. In this paper, a flexible force stabilizer for clamping ultrasonic bone knives is designed based on active-passive combined control mode. A flexible element is added in the ending grasp device to eliminate the sudden change of the contact force. An adaptive fuzzy controller is designed outside the loop to adjust the ideal contact force between the osteotome and the lamina according to the difference with the actual contact force for real-time adjustment. Through comparison experiments, the validity and feasibility of the active-passive combined hybrid control method for the contact force control of the end of the bone knife was verified.