Target Capturing Control for Space Robots with Unknown Mass Properties: A Self-Tuning Method Based on Gyros and Cameras

• Main Authors: Zhenyu Li, Bin Wang, Hong Liu
• Format: Article
• Language: English
• Published: MDPI AG 2016-08-01
• Series: Sensors
• Subjects: free-floating space robot; autonomous target capturing; space robot modeling; self-tuning control; mass property estimation
• Online Access: http://www.mdpi.com/1424-8220/16/9/1383

Satellite capturing with free-floating space robots is still a challenging task due to the non-fixed base and unknown mass property issues. In this paper gyro and eye-in-hand camera data are adopted as an alternative choice for solving this problem. For this improved system, a new modeling approach that reduces the complexity of system control and identification is proposed. With the newly developed model, the space robot is equivalent to a ground-fixed manipulator system. Accordingly, a self-tuning control scheme is applied to handle such a control problem including unknown parameters. To determine the controller parameters, an estimator is designed based on the least-squares technique for identifying the unknown mass properties in real time. The proposed method is tested with a credible 3-dimensional ground verification experimental system, and the experimental results confirm the effectiveness of the proposed control scheme.