Motion Planning and Pose Control for Flexible Spacecraft Using Enhanced LQR-RRT<sup>*</sup>
Xilin Zhong, Zhengtao Wei, Ti Chen
Abstract
The primary difficulty of on-orbit services is autonomous real-time motion planning, especially considering collision avoidance among complex modulars. This study considers the motion planning and control of flexible spacecraft in on-orbit service. Moreover, a typical flexible spacecraft consisting of flexible appendages and a rigid hub is modeled in this article. The rapidly exploring random tree star (RRT <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">*</sup> ) algorithm and linear quadratic regulator (LQR) are used to generate a path considering both collision avoidance and dynamic performance. A control algorithm is also designed to drive the spacecraft to track the planned path. Furthermore, the calculation difficulty, in which the target state of LQR is nonzero, is addressed in this article, and an algorithm is designed to estimate the node velocity. To show the advantage of the enhanced LQR-RRT <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">*</sup> method, some numerical motion planning results are presented for flexible spacecraft considering vibration suppression.