NASA needs robots to do the jobs in space that humans can’t. That’s why our customer Wyle Laboratories designed Robonaut 2 or R2. Its mission: Take on the most dangerous tasks alongside astronauts on the International Space Station. But first came training and testing. Stratasys Direct Manufacturing built a one-to-one 3D printed mockup of the robot that could do many of the same complicated tasks. Not only did the mockup R2 perform, it was faster and less expensive to make than anyone expected.
Wyle Laboratories is a leading provider of high-tech science, aerospace engineering and information technology services to the federal government on long-term outsourcing contracts. Wyle’s Integrated Science and Engineering Group in Houston helped NASA develop the Robonaut 2 (R2) for outer space.
While most current space robotic systems, such as robotic arms and exploration rovers, are designed to move large objects, R2’s tasks require more dexterity. Its mission was to work alongside astronauts, taking over repetitive and dangerous tasks. Its form factor and dexterity were designed such that R2 can use the same space tools and work in environments suited for astronauts.
One of Wyle’s responsibilities under the contract was to build a one-to-one scale, high-fidelity mockup of R2 for use in the simulation of potential missions. The exterior of the mockup had to duplicate the geometry and appearance of the actual R2. The limbs of the mockup had to be easily moved into the same positions as the real robot. And, the mockup had to withstand rough handling that it might receive during simulation and training.
“The geometry was very complex and we were under time constraints to produce the mockup,” said Robert Stevenson, mechanical designer for Wyle Laboratories. The parts have so many compound contours that it would have been very difficult to hold them during finish machining. One consequence is that they would have had to be thicker than on the real R2, which would have added to the weight of the mockup. The estimated delivery time for conventional machining for the mockup was 8 months and the cost was $180,000.
“FDM was a good fit for Wyle Laboratories because of its ability to create complex geometries,” said Jeffrey Gangel, account manager. “FDM also provides the high level of accuracy needed to ensure that the many pieces required to build the mockup fit together during assembly. Finally, with the largest installed base of FDM machines and the largest inventory of FDM materials in the world, they were able to meet the tight timeline for the project.”
“Our manufacturing lead had used the company in a previous job and had good results,” Stevenson said. “I sent the CAD models for quotation and evaluated the mechanical properties of the Fused Deposition Modeling (FDM) materials on the website. The ABS material met our strength and durability requirements. They were also very helpful in educating me in what I needed to do to get our CAD models ready for digital manufacturing.”
The interior of the mockup was made from square tubing to provide strength and the mockup was positioned by tension in its joints like a mannequin.
“NASA was very happy with the mockup,” said Gina Young, project manager for Wyle Laboratories. “They liked the fact that it was produced on schedule, was light compared to the original and was strong enough to withstand the large amount of handling it has received. The mockup has made it much easier for the crew to train and prepare to utilize the R2.” It took two weeks and cost $36,000 to make all of the parts required for the mockup.
The R2 flew to the International Space Station in 2011 on the Space Shuttle Discovery’s last flight. Initially, R2 was deployed on a fixed pedestal inside the ISS for operational testing. Next steps include adding a leg for climbing through the corridors of the ISS and further upgrades to go outside in the vacuum of space.
