Design and Experimental Verification for Ball Linear Guide Rail of Robotic Arm’s End Effector in China Space Station

A design scheme was proposed for the ball linear guide rail used in space mechanisms to improve the adaptability to the space environment. Testing the product of guide rail on ground and on-orbit, the results show that the design scheme can meet the requirements of on-orbit use and achieve long life applications of the guide rail in complex space environments such as vacuum and high and low temperatures. Taking the development of a ball linear guide rail for the end effector of a space station robotic arm as an example, the guide rail design and guide rail experimental verification were carried out. A solid lubrication scheme was determined, taking ball sputtering deposition of MoS₂ composite film for the guide rail, with a gap of 0.04~0.05 mm, being meet the service life requirements of the end effector working in orbit for more than 2 000 times. But the results of the guide rail test show that the load capacity and service life of the solid lubricated guide rail can significantly decrease. So the development process of guide rails for space mechanisms, the special life tests must be conducted to verify whether the guide rail can meet the requirements for on-orbit use.