Motion Visualization and Human-Robot Shared Control for Robotic Excavators

When a robotic excavator is controlled by a human operator, it must comply with the intention of the operator. Besides, it must meet the safety and operational quality of construction indicators. Coordinating the relationship between the active decision of the operator and the accurate control of the machine system is the key issue of this paper. Flexible virtual fixtures are proposed to control trajectory of the robotic excavator, the input signal of the restricted motion direction is weakened by introducing the flexibility coefficient kτ. In this way, a human-robot shared control system for the robotic excavator is built. Trajectories are designed to validate the performances of the flexible virtual fixtures, and experiments are performed on the trajectory control and motion visualization system which is built based on virtual instrument. The results show that the flexible virtual fixtures reduce the tracking errors and the operator can avoid the obstacle on the trajectory.