Design and Dynamics of a Cable-Driven Flexible Crawling Robot

With the rapid development of aerospace technology, many challenging aerospace missions have been proposed. The assembly of large-scale space structures, such as solar panels, space telescopes, and space antennas requires high precision modular assembly on orbit. Hence, a crawling robot is required that can crawl freely on the surface of the spacecraft, carry out the on-orbit operation and modular assembly. In this paper, a cable-driven flexible crawling robot is designed, which has the merits of light weight, small volume, simple drive, all-round movement and the abilities of successfully completing complex crawling for detection, searching, rescuing work, on-orbit assembly, service and operation. Firstly, a topology optimization model of the robot structure is established based on the density method. The method of moving asymptote is utilized to solve the corresponding optimization problem. During the topology optimization, the symmetric and antisymmetric of the robot structure is taken into consideration, so that the mass of the robot can be reduced up to 85%, which greatly improves its dynamic performance. Secondly, according to the terrain environment, various kinds of gaits of the crawling robot are designed and presented via conceptual diagrams. The lengths of the driving cables are measured and fitted for these gaits. Finally, with the help of 3D printing technology, a prototype of the crawling robot is completed and assembled in module. The cables are driven by eight steering engines controlled by a single chip computer, so that the flexible cramming robot can move in all directions. The designed gaits such as standing, turning and standing again, rotating in place, as well as wriggling and turning forward are tested and programmed under different environments, so that the feasibility of various gaits of the flexible crawling robot driven by cables is verified.