By Paolo Fiorini, B.E. Ph.D. Business Development Manager, ENBIO
ENBIO Ltd. is an Irish SME involved in the EIRSAT-1 programme, supporting the development of the EMOD module.
BACKGROUND
ENBIO is an Irish SME developing innovative next-generation surface technologies. ENBIO was founded in 2006 by our current CEO, John O’Donoghue. Having patented our primary coating technology, CoBlast, ENBIO spent a number of years pursuing the medical device sector with a synthetic bone (hydroxyapatite) coating for orthopaedic implants. Soon after, an opportunity arose to use a similar material to protect one of the European Space Agency’s (ESA) most ambitious projects to date – Solar Orbiter. ENBIO have always liked a challenge and this one was our greatest yet – to develop a protective coating for what will be the closest man-made object to orbit the sun. And so ENBIO pivoted into the Space sector in 2011 through this collaboration with the ESA and its project prime contractor, Airbus Defence and Space (UK). Since then, ENBIO have continued to branch out into commercial Space applications and subsequently decided to look back to Earth at various applications; most notably mould release coatings for rubber moulding and novel REACH-compliant metal primers for corrosion inhibition and metal bonding applications. All ENBIO’s coatings are environmentally compatible and do not use toxic chemicals.
SOLAR ORBITER – SOLARBLACK and SOLARWHITE
So what exactly was ESA’s challenge back in 2011? Well, Solar Orbiter aims to orbit the sun to within 42 million km (0.28 AU) at its closest approach and therefore needs to be protected from 25 times the solar flux experienced on Earth’s surface at temperatures up to 600 ˚C. Not only that, but due to the elliptical orbit it will also endure temperatures as low as -200 ˚C. So ENBIO used our CoBlast process to coat thin titanium foil (50 µm thick) with a black ceramic powder which we named SolarBlack. This coated foil makes up the first line of defence on Solar Obiter’s primary heatshield (2.5 x 3.5 m) and keeps the remainder of the satellite at about room temperature. SolarBlack is extremely stable, particularly when applied using the CoBlast process as it provides a direct-to-metal bond with the substrate. The coating is inorganic so it does not outgas volatile organic compounds which could hamper measurement instruments, it is electrically conductive so the satellite doesn’t short circuit, and most importantly, UV testing has shown it will maintain its vital thermo-optical cooling properties over the intended lifetime of the satellite like no other coating. From concept, through development and testing, ENBIO delivered our SolarBlack thermal control coating on full flight hardware in under 3 years for this project – making it the fastest adopted technology by ESA by at least a factor of two. As a result, SolarBlack is now a baseline coating for Solar Orbiter and is used on multiple sun facing surfaces on the satellite including several smaller instrument heatshields, solar array boom arm panels, and even the main high gain antenna and sub systems.
Further to this ENBIO developed, in conjunction with UCD Engineering, a second coating for ESA. ESA set a second challenge; they wanted a white coating for Solar Orbiter’s radiator panels with higher reflectivity thermal properties more typical of a white coating. No other white coating on the market could withstand this harsh environment due to the solar flux. SolarWhite was also brought from concept to flight hardware in 4 years.
EIRSAT-1
More recently ENBIO were fortunate to become involved in the EIRSAT-1 project. While SolarBlack and SolarWhite are being used on the Solar Orbiter scientific mission, there is also scope to use these coatings on commercial satellites. However, performance data at Earth orbits is required and EIRSAT-1 presents ENBIO with the opportunity to measure and correlate coating performance in orbit, which is a very exciting prospect. EMOD is one of the two modules on EIRSAT-1 and will feature both SolarBlack and SolarWhite panels which will be monitored for temperature fluctuations during orbit. ENBIO are directly funding an EIRSAT-1 team member, a UCD engineering PhD student, and supporting both summer students and masters students working on EMOD. ENBIO are giving in-kind support through access to ENBIO’s test equipment, 3D printing facilities and surface engineering experts.
ENBIO’s FACILITIES
ENBIO has two locations – our head office and R&D labs are located in Dublin and our dedicated Space Technologies Centre is in Clonmel, Co. Tipperary. The ENBIO Space Technologies Centre was funded by the European Space Agency (ESA) and others, and is ENBIO’s centre of excellence for the production of Thermal Management treatments for satellites, spacecraft, and space related hardware. It contains two fully independent production lines for SolarBlack and SolarWhite, test equipment and two 8 m3 ovens designed for the SolarWhite curing process. These facilities are where the test coatings for EMOD will be performed and the payload will be assembled – under the same conditions and with the same care and procedures that every other piece of flight hardware for Space receives when coated by ENBIO.
Further Reading on Solar Orbiter:
Ultimate sunbather: NASA and ESA collaborate on Solar Orbiter, by Tim Harris of Airbus
Materials make the space mission, by ESA’s Tommaso Ghidini: