Boosting rocket production

Annie Doris spent nearly every day of the past school year at a factory filled with robots that were working feverishly to erect the chassis of an enormous rocket.

No, she hasn’t been spending time on the set of a science fiction movie. Doris has been interning at Relativity Space, a vertically integrated technology platform that is creating the world’s first 3D-printed rocket.

“It has been amazing to witness and play a part in the printing of Relativity’s first rocket,” she said. “For me, it was really cool to see the evolution of that process. It is just crazy how quickly things progressed.”

Doris worked on the robotics and additive weld simulation teams. She collaborated with a group of engineers who are pioneering a process to enable robots to automatically detect and correct defects in real time.

“Everything is different in what Relativity is doing because the 3D-printing manufacturing process is so new. A lot of things that have been done traditionally in aerospace no longer apply or have to be adapted for this new process,” she said. “That’s what makes the work fun: it is both extremely exciting and challenging because there is not a lot of precedent.”

On the additive weld simulation team,  she was the owner of a project to characterize the stress states of 3D-printed rocket components. Her work involved modeling of the printing process to understand these stresses and to compensate for distortion.

“If you were to just print according to the design, you would end up with a structure that is distorted and not in the desired shape because of the rapid temperature changes that occur during the welding process,” Doris said.

She found it fascinating that physics-based computational modeling could be used as a tool to inform how robots should be “path-planned” to construct the rocket.

Doris, a joint mechanical engineering and physics concentrator, has drawn on the skills she’s developed at the Harvard John A. Paulson School of Engineering and Applied Sciences to tackle such complex problems.

Her research in the lab of Robert Wood, Charles River Professor of Engineering and Applied Sciences, inspired her to pursue an internship at Relativity Space. Last summer, she planned to work in the Wood Lab to build a robotic arm from soft materials, but after the labs closed due to COVID-19, Doris had to modify her plans.

Instead of working on a hands-on project, she conducted finite element modeling—building a model of an actuator for the robotic arm to optimize different geometric properties of the actuator.

She was surprised by how much she enjoyed the modeling work.

“So when I interviewed at Relativity, one of the things that sounded really appealing to me was that they were doing a lot of modeling of the printed rocket components,” she said. “It sounded like a really cool opportunity to expand that skill set.”

It was a fun challenge to keep pace with the rapidly evolving environment at Relativity, Doris said, and the work often required a lot of multitasking to keep everything running smoothly.

“With the complexity of problems we were trying to solve, you could start a number of research labs out of the work currently underway at Relativity,” she said. “It was thrilling to think about these deep problems while also scrambling to get a rocket to the launchpad,” Doris said.

The launch of Relativity’s first rocket, Terran 1, is slated for later this year.

Doris, who just began a summer internship at Amazon Robotics, isn’t sure if she’ll pursue a career in aerospace engineering or robotics, but her experiences so far have inspired her to keep seeking out thorny problems to solve.