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Space grippers are the key devices for accomplishing space non-cooperative target capture, which has a great significance for satellite services and space debris removal. This article proposes a novel mechanical gripper device for the capture of aluminum honeycomb panels of non-cooperative satellites. The gripper was modeled and assembled in the three-dimensional modeling platform UGNX. The model was imported into the simulation software ADAMS. ADAMS is capable of analyzing the kinematic feasibility of the gripper model. Collision and penetrating power analysis of the mechanical claws into an aluminum honeycomb plate were carried out in LS-DYNA. Through non-vertical piercing experiment, the maximum approaching angle tolerance is 10°. The established rigid connection can withstand a destructive force greater than 1000 N. A prototype of the mechanical gripper is built. A ground test was carried out with this prototype, in which a test-platform simulated the space microgravity environment. The results certified that the prototype could reach the target at a relative speed of 0.5 m/s and then quickly complete the grabbing motion and establish a rigid connection. The experiment shows that this mechanical gripper can accomplish the task of repeatedly capturing the surface of non-cooperative space satellites.

This article presents the kinematics model and control simulation of a hydraulic boom. This hydraulic boom is used on the logging harvester, which is a typical forestry vehicle. The kinematics equations of the hydraulic boom and the transformation between joint variables and hydraulic cylinder variables are obtained for the control purpose. An autonomous control method is suggested for the harvesting head to capture trunks. There are two separate closed loops in the control scheme: the inner closed loop realizes the control on the hydraulic cylinders, and the outer loop plans the desired trajectory of the harvesting head to capture trunks based on the laser measurement data. An interactive real-time dynamic simulation system is developed, and the proposed control method is verified.