Teleoperation for space manipulator based on complex virtual fixtures

This paper presents a kind of complex virtual fixture (VF) to help space robots perform on-orbit operations in complex environments while ensuring operations safety. The main purpose of the VF is to provide virtual force feedback to adjust the manners of the operator throughout the remote operation process. The complex VF is comprised of a tube-type VF and a velocity-based VF. The tube-type VF ensures that the end effector approaches the target safely and at high speeds over long distances, and the velocity-based VF enables the end of the robot to observe the target within a safe and short distance near the target. Combined with dynamic prediction and path planning, the complex VF can improve the flexibility and efficiency of the operation, and avoid collisions in dynamic environments. The proposed methods are verified by several typical space manipulation tasks, the virtual experiment environment of which is built in CHAI3D. The comparative results indicate that the complex VF can reduce operation time and improve efficiency and accuracy. (C) 2019 Elsevier B.V. All rights reserved.