Abstract: In response to the demand for miniaturization and lightweight design of rendezvous and docking products, a LiDAR system based on a MEMS two-dimensional scanning drive unit was proposed. To meet the requirements for long-range rapid acquisition and stable tracking, the optical system was designed to determine energy parameters, the MEMS scanning drive method and search-capture strategy were developed, and a ground-based long-distance search-capture validation test was designed. Firstly, the MEMS-based LiDAR optical system was designed, and based on the analysis of the spatial cooperative target echo energy model, the key parameters of the fiber laser, APD detector, MEMS scanning mirror, optical transceiver system, and laser cooperative target were determined to meet the requirements of long-distance detection at the 30km level. Secondly, the Lissajous single-frame scanning curve for the MEMS unit and the square-ring multi-frame scanning search and acquisition strategy were designed. Finally, the influence of atmospheric two-way transmittance on the maximum ranging capability under ground conditions was analyzed, along with the effects of light intensity fluctuation and spot drift under turbulent atmospheric conditions on ground-based testing. A ground-based long-distance search and acquisition experimental platform was established, and both ground-based static power tests and dynamic captive-carry flight tests were designed. At a distance of 28.6km, the target was rapidly acquired within 15 seconds while meeting dynamic performance requirements of ±5(°)/s. Experimental results verify that the optical system design of the MEMS LiDAR satisfies the 30km-level ranging capability in orbit, and the search and capture strategy design meets the requirements for rapid acquisition and stable tracking. This lays a foundation for the application of miniaturized and lightweight LiDAR products in future rendezvous and docking missions.

Key words: rendezvous and docking, MEMS LiDAR, spatial cooperative target, acquisition strategy design, ground test design