Research On Development And Experiment Of Space Manipulator Joint Brake

With the development and progress of space on-orbit service technology, space manipulator, an Electronics-Mechanism Integrated equipment as an alternative of astronauts for space operations, has been successfully applied on the International Space Station. As part of the manipulator for guarantee of safety and security of the equipment, the design and performance of a manipulator joint brake is directly related to the safety of the manipulator body and the end-loads. Lots of work is essentially necessary on the material selection, designing and testing for the joint brake so as to deal with the extreme working conditions in the outer space.This paper proposes a designing and experimental method for a manipulator brake and designs an brake for the space manipulator which can be applied in the space environment.In this paper, based on the reviews of various types of domestic and foreign industrial brakes and space manipulator brakes, the key problems of designing space manipulator brake were concluded and the existing optimization methods of the brake were also summarized. In the reference and summary for all types of domestic testing tables for brakes, testing methods for space brake were proposed.Secondly, according to the parameters and the work environment of a particular model of mechanical arm, the design specifications was determined and the structure of plate fail-safe disk brake was designed, which shares a few characteristics like a large brake torque, large center hole and so on. Material selection for all the component parts and finite element check for the key components was conducted so as to ensure the safety and reliability of the design. According to structure specifications of the brake, the corresponding testing platform for measuring the performance of the brake was designed and also experimental platform with the capacity to conduct a thermal vacuum measurement was constructed based on the existing equipments in the laboratory. Besides, the corresponding control system was finished for the measuring project.Thirdly, with the accessible electromagnetic designing method, the solenoid coil, a key component of the brake, was designed. Using Ansoft Maxwell software, finite element simulation of two-dimensional steady state and three-dimensional transient state for the parameters of the solenoid coil was conducted to verify the rationality and reliability of the design. Genetic algorithms were also adopted to optimize the parameters of the solenoid coil, hence, reducing the coil temperature rise.Finally, measurement and verification of the braking performance of the brake were conducted on the testing platform designed. The performance of the brake working under normal braking torque and thermal vacuum environment was measured to ensure that the brake satisfies the performance requirements...