Experimental study on autonomous assembly of multiple spacecraft simulators in a spinning scenario

Utilizing the autonomous rendezvous and docking among multiple spacecraft to construct a large space structure is a prospective on-orbit autonomous assembly mission. This paper presents a planar air-bearing experiment on the autonomous assembly of two chaser spacecraft simulators and one spinning target spacecraft simulator. The mission process includes four distinct phases. While the first two phases use the real-time assembly and collision avoidance controllers proposed, the assembly control laws with analytical expressions play its role in the remaining phases. Both neighboring spacecraft simulators and external object serve as the obstacles during the design process. The hardware-in-the-loop experimental system consists of three spacecraft simulators with electromagnetic docking mechanism installed, a granite testbed, a motion tracking system and a wireless transmission system. The experimental results show that the proposed multistage control strategy can successfully realize the autonomous collision-free assembly of three spacecraft simulators in the spinning scenario.