In 2012, the world watched as the Curiosity rover parachuted to the surface of Mars and began collecting samples. The data and images it sent back have helped us learn more about the red planet and the possibilities for life there, and it’s still on the job today. The mission was another important success for the designers and engineers at NASA’s Jet Propulsion Laboratory. But so far, little evidence of life on Mars has been found, past or present.
Now scientists think the most likely places we’ll find signs of life in our solar system lie on the moons of Saturn and Jupiter. But these gas giants lie much further away. At 35 million miles, the trip to Mars was short compared to the 365-million-mile journey to Jupiter. And Saturn is another 381 million miles past that. Getting landers to these distant areas presents far greater design and engineering challenges. To meet those challenges, JPL and Autodesk have engaged in a multi-year collaborative research project so that JPL can explore new approaches to design and manufacturing processes for space exploration, with the custom application of Autodesk’s generative design technology.
Mark Davis, the senior director of industry research at Autodesk, was part of the team that first approached JPL about a collaboration. “They were clear that they weren’t interested in incremental gains: if they were only able to improve performance by 10%, they basically weren’t interested. If we could deliver software tools to help them achieve a performance improvement of 30% or more, then we had their attention. This project demonstrates that Autodesk technologies may deliver mass savings at this level.”
The concept lander, perhaps the most complicated structure ever created using generative design, was unveiled at Autodesk University on November 13th 2018 in Las Vegas.
The Life of a Lander
To accomplish a mission like this, an interplanetary lander needs to perform complicated operational functions in temperatures far below zero and withstand radiation levels thousands of times greater than on Earth. But first, it has to have enough fuel to get where it’s going.
In space exploration, weight at liftoff is one of the most critical considerations. Every kilogram of mass that can be cut from the structural payload enables a critical increase in the scientific payload of sensors and instruments to search for life beyond earth.
Balancing the Proven with the Possible
In some industries, it can be considered a good thing to “fail fast” or get to a “minimum viable product” as quickly as possible, then improve it. But in space exploration, failure comes at a high cost. A mission typically only has one shot at success, with few viable backup plans. It’s understandable why the teams at JPL are careful when considering new processes. They stick with what works—qualified materials like titanium and aluminum that they know will hold up in the harsh conditions of space, and manufacturing processes like CNC machining that are mission-proven.
At the same time, they need to explore what new technologies can do for them, or risk being made obsolete by other companies. It’s always a balancing act between what’s proven and what’s possible.
Within the company, JPL’s Atelier division is the team charged with trying out new approaches and processes, then recommending the ones that hold promise to the teams working on specific missions.
“What they do is carefully infuse new technology into their processes,” says Karl Willis, Autodesk’s technology lead on the project. “They know they have to explore new ways to do things while keeping risk at a minimum.”
Innovation by Design
Generative design is a relatively new design approach that uses machine intelligence and cloud computing to quickly generate a broad set of design solutions that fit within the specific constraints set by engineers. It enables design teams to explore a much wider design space while still being bound by manufacturing and performance requirements dictated by the team or environment.
A commercial form of generative design technology is available today in Fusion 360, Autodesk’s cloud-based product development platform. Davis and his team in Autodesk’s Office of the CTO continue to develop more conceptual advanced versions of the software for use in experimental capacities, such as with JPL. “We had developed a custom version of our software for high performance motorsports that enabled us to help our customers solve for multiple constraints at once. We then applied it to the problems JPL needed to consider,” Davis says. “We took a system that was developed to help our customer solve system level suspension problems on a Formula One race car and applied new requirements for structural constraints critical to space exploration. This gave us a chance to push the capabilities of the software even further and help our customers solve even larger and more sophisticated problems.”
Generative design is often associated with 3D printing, also known as additive manufacturing, which is well-suited for the complex, organic-looking shapes that the software produces based on user specifications. But the software also gives users the ability to set constraints for their other manufacturing processes. “We now have the ability to help our customers solve for their multiple manufacturing constraints simultaneously, which adds CNC machining and casting options in addition to 3D printing,” explains Davis. And while other software programs can optimize a single part for stiffness and weight, Autodesk’s generative design technology is unique in its ability to allow customers to take into consideration alternate design strategies and produce an entire array of viable solutions, rather than just a single optimized version.
For the lander project, the JPL team explored the use of experimental generative design technology for multiple structural components, including the internal structure that holds the scientific instruments, and the external structure that connects the lander legs to the main payload box. The team has been able reduce the mass of the external structure by 35% compared with the baseline design that they started with.
Learn, Improve, Repeat
A key benefit of generative design is that it enabled the JPL team to iterate their designs rapidly. “As a design matures and new performance or environmental data comes in, generative design can enable our customers to create new designs quickly,” says Willis. Most design teams typically take 2-4 months to turn around a revised design, he points out. Working with generative design, that process can take place in 2-4 weeks. “That flexibility and speed to update an existing problem definition rather than starting from scratch, combined with the ability for customers to specify manufacturing constraints, make it a real paradigm shift for people designing these kinds of structures,” Willis says.
Creating a lander that can withstand the rigorous conditions of space across extreme distances is a massive challenge, and JPL’s designers are investigating and using every new technology at their disposal. For now, the application of generative design is still officially considered a developmental research project within JPL. But taking the seemingly impossible and making it possible is JPL’s specialty. Just as the computational power of mainframe computers helped the space program reach new heights in the 1960s, technologies like generative design are creating new possibilities in space exploration, enabling us to go further and learn more about our place in the universe.