Researchers at the German Aerospace Center (DLR) have developed MiniFix, a fully 3D printed syringe-based biological fixation system engineered for spaceflight. Successfully deployed in five MAPHEUS sounding rocket missions, MiniFix represents a breakthrough in experimental payload design, combining rapid prototyping, modularity, and robust performance in microgravity environments, combining rapid prototyping with modular, lightweight, and reliable performance under the extreme conditions of microgravity research.
MiniFix was developed by Sebastian Feles at the German Aerospace Center (DLR), where he designs modular, flight-proven hardware systems for life science experiments in space.
A 3D printing milestone for space life science
Unlike conventional biological fixation systems, MiniFix is entirely produced via Fused Deposition Modeling (FDM). Key components, including the syringe holders, baseplate, and housing, were fabricated using desktop 3D printers, notably a Prusa MK3+, with 0.4 mm nozzles and a 0.3 mm layer height. This approach enabled fast, low-cost iteration and customization of parts to suit different missions and experimental needs.
The system has undergone structural revisions using three different filaments; PLA (Polylactic Acid), used in initial missions (MAPHEUS-09 and -12), PETG (Polyethylene Terephthalate Glycol), chosen for enhanced mechanical durability (MAPHEUS-14), and GreenTEC Pro, a compostable bioplastic with high thermal resistance, used in MAPHEUS-15. This made MiniFix the first biologically compostable experimental structure to fly aboard a rocket.
Modular design for rapid adaptation
MiniFix features a dual-syringe configuration, where a fixative and a biological sample are housed in vertically stacked syringes. Syringe actuation is handled by NEMA11 stepper motors coupled with linear actuators, allowing precise fluid dispensing. The hardware is modular and sterilizable, enabling pre-assembled syringe units to be installed under sterile conditions.
Its all-3D printed chassis ensures that custom features, like integrated lighting for plant experiments, can be introduced quickly without redesigning the core system. This makes MiniFix suitable for various biological models, from unicellular organisms to organoids.
Built-in thermal regulation via waste heat
A standout innovation is MiniFix’s passive thermal management system, which uses the heat generated by its stepper motors to maintain stable internal temperatures. With no need for separate heating elements, this system simplifies design, reduces power draw, and lowers overall payload mass, critical factors for sounding rocket missions with strict weight and energy budgets.
Test data from MAPHEUS-15 showed that MiniFix maintained an internal temperature of 21.98 °C ±0.12 °C, consuming just 4.6 Wh during operation, even under ambient conditions as low as 4 °C.
Space-tested reliability
The reliability of this 3D printed structure was put to the test across multiple missions. MiniFix successfully endured extreme conditions, including launch vibrations exceeding 20 g and temperature swings from hypergravity to microgravity and re-entry. Across five missions, its components have shown no degradation or material failure, with post-flight inspections confirming the integrity of all printed parts and mechanical systems.
Future applications
Beyond fixation, MiniFix could evolve into a general-purpose liquid handling system for space. Its syringe mechanism is already capable of performing programmable mixing and the platform could be adapted for reagent delivery, drug testing, or even microfluidics in space-based manufacturing. Additionally, it exemplifies how additive manufacturing can accelerate experimental development cycles while maintaining reliability in harsh environments. Its open-source microcontroller and modular design ethos further position it as a template for future experimental hardware in life sciences and beyond.
3D printing gains traction in space hardware development
Additive manufacturing is rapidly transforming the development of spaceflight hardware, from on‑orbit part fabrication to ground-based launch systems. Just this year, ESA’s Metal3D printer aboard the ISS produced the first metal 3D‑printed part in microgravity, now safely back on Earth for analysis.
Meanwhile, Nikon and JAXA are collaborating to refine large-scale metal 3D printing for space components, advancing materials and process control to shorten lead times and reduce launch costs. Within this context, DLR’s MiniFix system exemplifies a new wave of highly adaptable, mission‑specific payloads, completely fabricated using desktop FDM printers and bioplastics, optimized for the rigors of sounding rocket flight and microgravity research.
The full research paper, titled “Pioneering the Future of Experimental Space Hardware,” is available in Microgravity Science and Technology via Springer Nature.
Subscribe to the 3D Printing Industry newsletter to keep up with the latest 3D printing news.You can also follow us on LinkedIn and subscribe to the 3D Printing Industry YouTube channel to access more exclusive content.
At 3DPI, our mission is to deliver high-quality journalism, technical insight, and industry intelligence to professionals across the AM ecosystem.
Help us shape the future of 3D printing industry news with our 2025 reader survey.
Featured image shows a sectional, translucent view through the MiniFix fixation system. Image via Sebastian Feles / DLR.
