CASE STUDY 3d printed partS oF a SpaCe VehiCle Testing the rover An agile white vehicle roams the Arizona desert, manoeuvring the unforgiving terrain as the wind and sun beat down and temperatures range from one extreme to another. NASA astronauts and engineers are test-driving a rover over rocks and sand, up and down hills in an environment that simulates the brutal conditions of Mars to allow human exploration of the planet. The rover The rover is called Desert RATS (Research and Technology Studies) and is about the size of a pickup or SUV Hummer, with a pressurised cabin to support humans in space. Its twelve strong wheels on six axles turn over irregular, unsure terrain, and its protruding cockpit can tilt down to place its observation bubble low to the ground. 3D printed parts To design such a tenacious and specialised vehicle, NASA engineers used the advanced technology of 3D printing. About 70 of the parts 7 that make up the rover were built digitally, directly from computer designs, in the heated chamber of a production-grade Stratasys 3D Printer. The process, called Fused Deposition Modelling (FDM) Technology, patented by Stratasys, is the only 3D-printing method that supports production-grade thermoplastics, which are lightweight but durable enough for strong parts. FDM offers the design flexibility and quick turnaround to build tailored housings for complex electronic assemblies, suitable for Martian terrain. These exterior housings are deep and contorted and would be impossible, or at least prohibitively expensive, to machine. NASA engineers also 3D print prototypes to test form, fit and function of parts they will eventually build in other materials. This ensures machined parts are based on the best possible design by solving challenges before committing to expensive tooling. to beat down: picchiare housing: alloggiamento to protrude: sporgersi to tilt: inclinarsi turnaround: inversione di rotta unforgiving: spietato, implacabile answer the questions. 1. Why do NASA astronauts and engineers test the rover in the Arizona desert? 2. How big is the Desert RATS? 3. How many wheels and axles does the rover have? 4. What is the peculiarity of the cockpit? 5. How many parts of the vehicle were 3D-printed? 6. What 3D technology and material were employed? 7. Why did NASA engineers use this 3D printing method? 8. What are the positive aspects of FDM when you want to build tailored housings? 9. Why didn t NASA engineers machine the housings? 10. Why do NASA engineers usually 3D print prototypes? 8 groUp WorK 3d printing is an innovative and versatile technique for creating prototypes and scale models of parts and also end-use products for the automotive sector. go online and find examples of the advantages of using additive manufacturing in producing vehicles, then report to the class. Shaping and joining materialS 115 MechPower.indb 115 30/01/24 17:08
