Planetary transmission performance tests at very low temperatures

This article presents the results of a study on resistance to motion in a multi-stage planetary transmission, built with lightweight structural materials such as aluminum alloy 2017, with bearing nodes featuring steel ball bearings made from X65Cr14 alloy and lubricated with molybdenum disulfide powder. Details of the planetary gear construction were presented, followed by operational performance tests. During the performance tests, the temperature of the running transmission was gradually lowered with liquid nitrogen to as low as − 190 °C. The analysis covered, among others, the power consumption of the mechanism as a function of temperature. The results were compared with the parameters of the mechanisms already working in space. The measurements were carried out to confirm the applicability of the gearing in drive systems of manipulators intended to operate in open space or under extraterrestrial conditions such as on Mars.