Hybrid Vision/Force Control of Robotic Autonomous Assembly for 110kV Hot-line Maintenance

High-voltage transmission lines, also known as hot-lines, are the most important means of electric power energy transmission, the stability and safety of their manipulation and maintenance also have direct impacts on the quality of the power supply, as well as on workers’ lives and productivity. In this paper, A robotic nut tightening operation on a T-connector is taken as an example of live working, a hybrid vision/force controller is then proposed based on a depth camera, a 6-axis force/torque sensor and a parallel gripper. The depth camera is introduced to locate the position of the nut and the bolt to perform grasping, force controller is then used to insert the nut onto the bolt correctly to perform nut tightening. Meanwhile, an operation planning module is introduced to generate the desired trajectory according to the information given by the two controllers. The experimental results show high control efficiency with high recognition accuracy.