Research and Development

The application of ‘good tribology’ contributes significantly to the efficiency, reliability and performance of European Spacecraft mechanisms. ESTL offers independent, specialist support in this field for the benefit of the European Space mechanisms community. Part of ESTL’s remit is to research and develop lubricant coatings and other related tribological technologies for space mechanisms.

Tribology Applications Programme (TAP)

ESTL operates an annually defined Tribology Application Program (TAP), providing the means of generating essential tribological data for the benefit of the European space community in response to trends and advancements in spacecraft and a wider industrial context. Such data helps ensure the continuing success of mechanisms for ESA’s Member States. The TAP activities take into account inputs and requests for studies made by, and solicited from, European space industries and ESA itself.

Recent TAP activities have been performed in the following areas: 

• Hybrid lubrication (combined solid/fluid lubricant solutions)
• Improved solid lubricants (including improved PVD MoS₂, evaluation of potential future replacements for lead lubrication) and low-cost solid lubricants
• Component-level and actuator level assessment/characterisation (i.e. gears, gearboxes, bearing gapping, linear piezo actuators, self-lubricating composite cages, cage dynamics, electrical effects, hybrid ceramic contacts)
• Fluid lubricants (lubricant assessments, new ionic lubricants, creep barriers, impact of cage on free oil in bearings, evaporation behaviour, anomalous grease behaviour in low-speed ball bearings and lubricant degradation)
• Quantitative assessments of lubricant condition and inspection techniques, as well as literature and feasibility studies
• Film thickness measurements of fluid lubricated bearings and assessments related to accelerated life-testing of fluid and solid-lubricated bearing systems
• Ball bearing and lubricant performance analysis

The TAP activities are fully funded by ESA and as such all results are openly disseminated to ESA Member States.

R&D Support Hardware

To support these activities, ESTL has a comprehensive set of specialised vacuum test facilities available for space tribology research and development including:

• Vacuum Pin-in-Disc Tribometers (PoD) – Multiple sliding tribometers for assessment of friction and wear of solid and fluid lubricants. Testing can be performed under vacuum conditions, or under fully controllable cover gas environments. Operable over the temperature range -100°C to +200°C
• Spiral Orbit Tribometer (SOT) – A specialised class of rolling contact tribometer developed by NASA and uniquely accessible in Europe at ESTL, for assessment of lubricant consumption (i.e. life) and friction coefficients. The SOT features representative kinematics of an angular contact ball bearing (rolling and pivoting), and can provide friction data, and solid or fluid lubricant life/degradation results in much shorter timescales than conventional angular contact bearing tests (days or weeks not months or years). Operable over -50 to +120°C
• Gear test rigs – Fully automated bespoke testing hardware for spur gear component level tests as well as for the evaluation of gearbox unit level performance (for example harmonic drives/spur gears etc)
• Advanced Bearing Tets Rig (ABTR) – Angular contact bearing test facility featuring the capability to assess axial shaft displacement and active monitoring of bearing preload, allowing in-situ film thickness and/or wear or other raceway changes to be inferred for both compliant and hard preloaded systems
• Detailed support and inspection hardware – Including Residual Gas Analysis (RGA), Optical Microscopy with EDF imaging, Scanning Electron Microscopy (SEM), Electron Dispersion Spectroscopy (EDS), X‐ray Fluorescence (XRF), Non-contacting White-Light Profilometry, Pre-loading Press, Co-ordinate Measuring Machine (CMM) and µ-Hardness and Indentation

Commercial R&D

Where additional support is required by the client, or if our TAP activities do not directly relate to your development, ESTL can provide tailored and entirely confidential R&D on a commercial basis to organisations from around the world as appropriate. Please contact us for further information.

• Simon Lewis, Manager, ESTL
• E: This email address is being protected from spambots. You need JavaScript enabled to view it. T: +44(0)1925 843451
• Michael Buttery, Principle Project Scientist
• E: This email address is being protected from spambots. You need JavaScript enabled to view it. T: +44(0)1925 843437

Please download our R&D flyer here.