Investigation of hard lubricant coatings in space in orbit around the moon

Abstract

This paper reports onfriction tests of a hard lubricant coating conducted in orbit around the Moon. The measurements included those taken in terrestrial conditions in a vacuum chamber, at the launch site, and in lunar orbit. The paper includes a description of an autonomous friction simulator that was mounted outside the spacecraft. In this device, two types of friction, 'shaft-bush' and 'disc-indenter', have been tested. For the first time, a long experiment exploring the tribological characteristics of an antifriction coating in a real space environment in a lunar satellite orbit has been carried out. Over a fifteen-month period, the friction units were run in the space environment. These tests indicated a tendency for thefriction coelficient to reduce to a limit value in such an orbit and environment.Continued development of space travel involves the construction of satellites, space stations, and space vehicles, with long lifetimes. In this context, the performance of friction units in space is of interest, as a complete set of mechanisms and assemblies that can work outside a pressurised environment and under the influence of deep space factors must be developed. Additionally, it is very important to calibrate and understand the nature of testing of antifriction materials and friction units in terrestrial vacuum equipment. Since there are differences between closed terrestrial and deep space environment parameters, these tests were performed in the Moon's orbit, with the aim of using the results to construct new friction units for space stations.

Ultrahigh vacuum system for advanced tribology studies: Design principles and applications

“…So far, various vacuum test equipment has been developed to address the needs of specific tribological characterization of materials in vacuum and under controlled atmosphere [2,15,30,[35][36][37][38][39][40][41][42][43][44][45][46]. Some of these systems have optimal design, although "trial and error" has been the general approach.…”