Space debris capture is the base of the on-orbit servicing and space debris removal. Due to the lack of fixed grasping points and the uncertainty of motion parameters, the traditional spacecraft manipulator approach cannot be applied in the space debris capture. In this article, a novel adaptive capture approach based on origami principle is developed. Main advantages of the proposed method are as follows: (1) it can capture target without fixed points. Through multimodule unfolding, the capture mechanism can form a suitable configuration for the space debris, restrict its motion, and capture it. (2) As the caging configuration of the capture device can be changed through different module unfolding, it can satisfy different size of the space target. (3) It can save the launch space of the capture mechanism. The multimodule capture mechanism has small volume after folding, which can greatly save the storage space in launch stage. The structure of the capture mechanism based on origami principle is developed, and the grasping configuration design is proposed for different size of the space debris target. In addition, considering the disturbance in process of capture is nonlinear and is hard to obtain accurately, a novel extended state observer-based sliding control is developed for the capture process control. The simulation results demonstrate the efficiency of the control algorithm.

This paper presents an adaptive caging configuration design algorithm of the hyper-redundant manipulator for dysfunctional satellite pre-capture. Taking advantages of the extreme flexibility and hyperredundancy, the hyper-redundant manipulator wraps its whole body around the dysfunctional satellite to restrain its motion without requiring grappling points and accurate information. However, the hyperredundancy also makes the caging configuration design more complicated and challenging. In this paper, the dynamic sequential caging following algorithm based on rapidly-exploring random tree algorithm is proposed to search the caging configuration in real-time. First, according to the discretized caging trace, which is twining around the grasped object and selected based on the caging conditions, the joints of the hyper-redundant manipulator are divided into several groups in advance. Then, the joint angles are searched group by group to realize the match of the discretized caging trace by the hyper-redundant manipulator. As a result, the configuration between the grasped object and the hyper-redundant manipulator satisfies the caging conditions. The main advantages of the proposed caging motion planning algorithm lie in the avoidance of the inversion and the efficiency of computation. Finally, the pre-capture of two dysfunctional satellites with different shapes using a twenty universal joint manipulator is implemented, and the simulation results verify the efficiency of the proposed method. INDEX TERMS Caging configuration design, hyper-redundant manipulator, caging trace, dynamic sequential caging following algorithm, rapidly-exploring random tree.

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