A High-Certainty Visual Servo Control Method for a Space Manipulator with Flexible Joints

Area of Science:

• Robotics
• Control Systems
• Space Engineering

Background:

• Space manipulators with flexible joints present control challenges due to complex dynamics.
• Existing visual servo algorithms may lack certainty in intermediate states, increasing collision risks.

Purpose of the Study:

• To introduce a novel high-certainty visual servo algorithm for space manipulators with flexible joints.
• To enhance both kinematic and dynamic certainty for safer and more precise operations.
• To reduce the risk of collision by improving intermediate state control.

Main Methods:

• A three-stage motion planner in Cartesian space to control intermediate states and minimize position error.
• A joint space planner using fast gradient descent to optimize joint deviation from centrality.
• A Lyapunov dynamics model reference adaptive controller for enhanced anti-disturbance capability.

Main Results:

• Experimental validation demonstrated consistency between visual servo motion and planned states.
• Average joint deviation from centrality was less than 40%.
• Motion trajectory consistency exceeded 90% under various inertial load disturbances.

Conclusions:

• The proposed algorithm enhances the certainty of position-based visual servo (PBVS) methods.
• It effectively reduces collision risks in space manipulator operations.
• The method offers improved precision and robustness in dynamic environments.