The Additive Layer Manufacturing (ALM) is one of the key technologies that have been demonstrated to provide a significant added value for space missions. When repairs are needed during a mission aboard the International Space Station ISS and the necessary tools are not available, Alexander Gerst may experience difficulties performing his work. Therefore 3D printing technology directly on board of the ISS will allow producing on-demand tools, spares and components according to the needs. And what’s even better is that OHB is playing a leading role in many 3D printing projects relevant for space flight. This means that Alexander Gerst can simply “print” any tools he needs and perhaps one day in the future collect space parts from a lunar base. Yet, it is not only in the fabrication of replacement parts for the international space station that OHB experts are at the vanguard of 3D printing as they are also using the technology to produce satellite components and living tissue (just imagine Alexander Gerst were to injure himself in space and needed an implant).
As Amazon currently does not yet make deliveries to the ISS, it is of course more difficult to obtain the necessary spare parts in space. Accordingly, the team, led by Dr Marco Berg (head of manned space flight and exploration) has been working intensively for more than three years on “printing in space” and modifications to technologies to meet the requirements of the European Space Agency ESA. The purpose of the MELT (Manufacturing of Experimental Layer Technology) project is to use the ISS as a testing environment for trialing and operating a printer that is capable of producing high-performance components from polymeric engineering materials. Sonaca Space (Germany), Active Space Technologies SA (Portugal) and desktop 3D printer producer BEEVERYCREATIVE (Portugal) are also working on the project alongside OHB System AG. “Within MELT, OHB is responsible for identifying and testing the functional and mechanical components to be printed and modifying the printer to meet the safety requirements of a manned environment,” explains Dr Marco Berg.
Obviously, the moon would be an ideal place for installing a warehouse and space printing plant. For this reason, ESA has awarded a consortium comprising Comex, Liquifer Systems Group and Sonaca Space GmbH under the lead management of Human Spaceflight department at OHB System AG, a contract for a study looking for the implementation of 3D printing technology in a lunar base perspective. Known as URBAN, the project is specifically tasked with evaluating the feasibility and resource requirements for the implementation of 3D printing for building, expanding operating and maintaining a manned lunar base. The project team presented the interim results to ESA ESTEC on June 18, 2018. The project will also be showcased at IAC2018 in Bremen in October and has been selected for the Global Network Forum.
Light-weight parts specifically optimized to withstand the loads during launch as well as operation in space can be produced. At the same time, delivery periods and storage capacity can be reduced.
Yet, OHB’s activities go even further: An AM task force is currently exploring the scope for using 3D printing for satellite structures. This will involve the use of either light-weight metals such as aluminum or titanium or metal-coated high-performance polymers. “OHB’s role is primarily to modify the design of the satellite structures in such a way that they can be printed. Following this, verification and qualification of the 3D printed parts will be done together with our suppliers,” says Dr Marco Mulser, technology coordinator for additive manufacturing.
3D printing can offer a series of real advantages for space technology. In particular, it allows entirely new geometries hitherto not possible using conventional manufacturing methods. Thus, light-weight parts specifically optimized to withstand the loads during launch as well as operation in space can be produced. At the same time, delivery periods and storage capacity can be reduced thanks to the more efficient use of material during production and the possibility of fabricating parts only when they are actually required.
A telescope from the 3d printer for measuring the ozone layer
In a current project under Markus Thiel, head of mechanisms and products, a consortium comprising OHB, TNO, Fraunhofer IFAM, IABG, SRON and Materialise are working on a study for printing an opto-mechanical instrument, which is a two-mirror telescope for measuring the ozone layer. Due to the printing process the number of required individual components was decreased, simultaneously reducing the telescope mass to around 30% of the original figure. The project team recently presented the results of the work performed so far at the European Conference on Spacecraft Structures, Materials and Environmental Testing – ECSSMET2018. And this is not the end: OHB is currently working on several projects aimed at additionally improving the design and qualification process so that a greater number of 3D-printed components can be used in future OHB missions.
3D bioprinting turns living tissue into an implant
Satellite components from metals, tools made from plastics – fair enough! But the notion of using 3D printers to produce living tissue boggles the mind. Yet, it is already quite possible to obtain biocompatible implants from stem cells or cartilage, for example. Currently, the Life Sciences unit under Dr. Klaus Slenzka is working on a study under the ESA (European Space Agency) General Studies Program into 3D printing of living tissue for space. Dr. Klaus Slenzka, Head of Life Sciences, is very proud to have secured the innovative project for OHB SE as the main contractor and in cooperation with the Technical University of Dresden and OHB’s life sciences subsidiary Blue Horizon Sàrl. “Using 3D bioprinting, it will be possible to gain biocompatible implants from human tissue such as stem cells or cartilage," says Dr. Klaus Slenzka. The focus of the ESA study is on 3D bioprinting of bone and skin, which can be used in regenerative medicine. "If an astronaut is injured during a space mission, it will soon be possible to create an implant in the spaceship using a 3D bioprinter,” explains Slenzka. At the end of the 12-month study, the ESA research group will deliver a 3D tissue sample.