In the terminal proximity stage of autonomous rendezvous and docking, H₂ and H_∞ and guidance algorithms are adopted to overcome the influence on relative guidance accuracy of the following terms, the uncertainty of the system model, the noise of the relative information measurements and thrust misalignment. First of all, a widely used glide slope scheme is introduced to plan the ideal terminal proximity trajectory. Using this assumption the ideal relative position and velocity can be determined beforehand. And then, the tracking error equations for V-bar approach are derived. So the guidance problem is transformed to synthesize a controller to eliminate the tracking error to zero. Modern control methods are applied to design the H₂ / H_∞ controller. The LMI (linear matrix inequalities) technology is adopted here to get the final solution for controllers. Simulation based on the solution obtained though MATLAB^RLMI toolbox is performed on a scenario of the rendezvous and docking final proximity stage. The simulation results verify the validity and superiority of the H_∞ design method for the terminal proximity of autonomous rendezvous and docking.

Date Published: 10 November 2007
PDF: 7 pages
Proc. SPIE 6795, Second International Conference on Space Information Technology, 679556 (10 November 2007);

Published in SPIE Proceedings Vol. 6795:
Second International Conference on Space Information Technology
Cheng Wang; Shan Zhong; Jiaolong Wei, Editor(s)