ESR Space Design & Development
Gated Design Process (AS/EN9100:2018 Accredited)
Our design and development work is focussed on space and vacuum industries where the highest quality levels are required to survive demanding environments and operational extremes. We maximise reliability with a view to cost optimisation, for science missions to telecoms platforms and Newspace applications. Our design process has been accredited to AS/EN9100:2018 since 2020, with regular audits being successfully completed from the outset.
Mechanisms for Long-Life & Demanding Environments
Let ESR Space guide and validate your design using our AS/EN9100:2018 accredited design process.
We develop new designs and evolve existing ones. Our development plans focus on risk mitigation by analysis, prototyping and characterisation of performance. We pride ourselves on working in multidisciplinary teams to simplify mechanical systems, with the capability to guide projects from concept to delivery. We will develop customised test rigs when necessary to verify designs. The majority of verification activities can usually be completed in-house.
While it may be possible to avoid tribological components, as with flexure-type designs, the application of good tribology remains a pillar of our design tools. Often it is necessary to include tribo-elements in space mechanism designs. The ESR Space team specialises in the commercial application of knowledge gained by our world-leading research facility (ESTL), where recent advances, methods and new materials can be utilised to help partners develop more reliable mechanisms. Increasingly, there is a need to extend lifetimes or ensure survival in the harshest environments, such as deep space and lunar/planetary environments. This is where we excel, to optimise the overall mechanism.
Examples are provided to show the range of design work performed in recent years, such as the Motorised Umbilical Separation Device (MUSD) developed for Mars applications shown to right and 4 more designs described below.
ESA Development – Lunar Thermal Shutter (LDRLR)
ESR have worked with Almatech SA, Spacemech Limited and Space Science Solutions Limited (SSSL) to develop a compact and scalable, actively shuttered radiator, designed to be resilient to the dusty environment that will be encountered by many upcoming lunar missions, such as Argonaut/EL3.
Radiator function is influenced by extreme temperature variations, where thermal cases must consider solar input and IR heating from the surface during the lunar day as well as heat losses during the lunar night. An actively shuttered approach enables closure of the radiator to minimize heat losses at night and/or to protect the radiator from contamination during events with high expected dust deposition, such as landing, astronaut, rover or robotic activities, or the passing of the day/night terminator.
The overall approach has been to maximize functionality across a wide range of lunar cases, with an emphasis on polar scenarios including lunar landers, payloads and rover applications.
Polymer Flex-pivot for Roller Tensioning in the Lunar Thermal Shutter Mechanism
A number of dust mitigation measures were implemented in the lunar shutter design (as described in previous example), from simple techniques such as selecting geometry to minimize dust ingress into sensitive areas, through to more elaborate measures such as lightly preloaded polymer seals used to keep dust out of the wheel bushings.
A flex-pivot support, utilising the Almatech technology – patent EP3371061 “Large Angle Flexible Pivot” (breadboard flex-pivot shown at left), was selected to support the retractable film of the thermal shutter. Selection was based on it’s inherent dust-resilience and long predicted lifetime for the actuation scenario of the mechanism.
Calibration Mechanisms for EO
EarthCARE Broadband Radiometer Calibration Mechanism Assembly
The mechanism consists of two nested bearing assemblies driving a chopper drum and a calibration drum. The former controls the passage of light into the three telescopes while the latter positions the viewing baffles and calibration sources, which are intermittently brought into view to calibrate the instrument.
Although both consist simplistically of a brushless DC motor and optical encoder, both have very different operational requirements in terms of load, lifetime and motion profiles.
More information can be found in the following ESMATS paper on the EarthCARE.
Precision Optical Mechanisms
SPICE Scan and Focus Mechanism
The Scan and Focus Mechanism (SFM) is one of four mechanisms that form the SPICE (SPectral Imaging of the Coronal Environment) instrument. SPICE is a high resolution imaging spectrometer operating at ultraviolet wavelengths and is one of six remote sensing instruments on Solar Orbiter.
The mechanism is required to continuously scan during three 10-day observation windows per orbit, with a total of up to 160 days of observing over nominal and extended operations. This equates to almost 70,000 end-to-end scan cycles over the full 8 arcmin rotation range (equivalent to 16 arcmin on the solar disk), with nearly 6000 allocated to ground activities before the application of lifetime factors. The minimum slit width is 1 arcsec and the repeatability target is ±0.1 arcsec.
Focus adjustment will be performed as required during in-orbit commissioning and between observation windows over a range of up to ±0.5mm with 64 and 32 full cycles allocated to ground and orbital cycles respectively. The required resolution is 1µm or better although adjustment steps will typically be at 5µm intervals.
The mechanism is designed to provide nominal performance between -30°C and +60°C and is required to withstand non-operational temperatures during flight of -60°C to +65°C. The SFM is also subject to the strict contamination requirements of an extreme ultraviolet
optical system, which impacts aspects such as lubrication selection and process control. Consistent with previous similar solar missions such as the long-lived SOHO spacecraft, the use of only solid lubricants was specified.