Friction in Rolling Element Bearings at Ultra-Low Speeds: A Review

Abstract Michael Lovell contributed significantly to the science and application of ball and rolling element bearings subjected to uniform and oscillatory motion at extremely low speeds. The control of friction in such operating conditions is paramount in precision positioning instruments such as satellites, telescopes, and robotics applications, where the Columb friction and Stribeck characterization of friction do not apply. This article concisely reviews the salient features of ultra-low-speed operation covering dry (unlubricated) and lubricated with various types of oil, grease, and solid lubricants primarily based on extensive experimental and computational analyses performed by Lovell.