Project Launched to Predict the Suitability of Rolling Bearing Greases in Robot Technology

Lubricated elements in robotics must guarantee low frictional and low breakaway torques that remain constant over the lubricant service life, and the lubricants used must not be subject to increased ageing due to the changing loads, and the lubricated components must operate with low wear over the entire projected service life. The lubricant represents an important control element for ensuring performance, operating speed, positioning accuracy, energy efficiency and availability. This is where the project, which was started on 01.12.2018, is to start, in which the friction and temperature behaviour and thus the suitability of the greases for the intended use is to be modelled and made predictable. Today, the friction of grease-lubricated bearings can only be calculated using partially empirical approaches. The reasons for this are starvation at high speeds or small reversing processes and losses in the grease structure outside the rolling contacts. All processes are determined by the rheology of the grease and its components as well as by the physical interactions between the thickener structure, base oil, and between the grease components and solid surfaces.

Physically based models are still missing here. This gap is to be closed at the research centres IMKT and ITR. The result is the interlocking of CFD simulation, laboratory measurements, and experimental investigations on test benches. A prerequisite is the formulation, verification and implementation of suitable rheological and physical models for fats as well as the fluorescence-optical observation of fat distribution and movement.

Research Centres

IMKT Institut für Maschinenkonstruktion und Tribologie, Leibniz University Hanover

ITR Institut für Tribologie und Energiewandlungsmaschinen TU Clausthal

Cooperating Research Association

FVA Forschungsvereinigung Antriebstechnik e.V.