Robotics students get down to nuts and bolts with JPL engineers

So when they had the chance to present their preliminary robot designs to a room of JPL engineers, including many Mars Rover alums and Mars2020 Rover team members, they weren’t looking for a pat on the back. They were there for nitty-gritty mechanical shop talk with some of the nation’s preeminent engineers. There was no time to be intimidated. They’d been working since August on their preliminary robot designs and, with their first league meet of the year just a week away, they wanted expert input on things like wheel compliance (aka squishiness), active vs. passive wheel intake, deployment mechanisms, and stress analysis. It all really came down to one question: “How can I make this robot better—faster, stronger, lighter.”

So, after identifying their favorite Girl Scout cookies (frozen Thin Mints, anyone?) the JPL review panel got straight down to business. 

First, the students explained the setup for this year’s FTC Challenge, called “Skystone,” which tasks teams with engineering a robot that can quickly and efficiently collect giant plastic “stones” and build them into stacks. Both Mayfield-based teams told the JPL reviewers that they wanted their robots to be “very robust and structurally sound,” while minimizing size, weight and failure potential. Plus, they’re taking on a new challenge this year: the maximum allowable robot size is an 18-inch cube, but there are bonus points for teams who can maneuver their robots under a 14-inch “skybridge.” So, students were open to all suggestions for making a more compact machine.

Each team presented early iterations of their designs, as well as plans for improvement. “As we went through each of our mechanisms they asked about the structural integrity, the reliability, and how it would be integrated into our final robot design,” said second-year Javabots team member Agnese Sanavio ’20. 

At the beginning of the season, each team split into subgroups to tackle individual mechanisms separately. The drivetrain team wanted a stable, high-speed and, above all, compact foundation for the robot. While their new omni-directional wheels offered back-and-forth, side-to-side and diagonal movement, they added bulk. How could they arrange them most efficiently? The claw mechanism team wanted better grip on the arm that retrieves and stacks “stones.” How could they make sure not to drop the stones and lose precious time and points? The turntable team needed to make their motor faster. How could they speed up the the motorized Lazy Susan to get those blocks turned around and ready for stacking?  

After the FTC “Skystone” challenge was launched in September, students first brainstormed to devise a game strategy that maximizes point-earning opportunities and an efficient, competition-ready robot design that complies with size and weight limits. As a team, they had to collaborate, iterate, and get creative with problem-solving, all while mastering new technical skills and meeting deadlines. Most importantly, they had to allow time to test and retest their ideas on the simulated game “field” they’ve set up in the Hayden Turner Center. 

“Overall we all felt the review board was extremely helpful because they helped us identify weaknesses in our mechanisms we had not considered before and ways we could work to fix these problems,” said Agnese.

Along with very specific tips for things like cable management (minimum bend radius is six times the cable diameter, FYI) the review team pushed students to experiment more widely with virtual design using computer-aided design (CAD) software before they build. Both teams used Onshape, a cloud-based CAD program that enabled them to build a virtual prototype and test different mechanisms, motors and layouts before they moved on to buying parts or building custom 3D-printed elements.

“The Onshape software helps you see if you're going to be putting a lot of stress on a mechanism, and you can also mesh mechanisms with other mechanisms to see how they would work,” said Agnese.

Students also used the review panel as practice for the FTC judging presentations that come later in the season during higher-level tournaments. 

“It was a great experience for all the girls on our team and it was a great glimpse into what engineers do on a day-to-day basis,” said Agnese, who is planning to major in mechanical engineering.  

The evening may not have ended with congratulatory high fives or hugs, but the students definitely felt like they had earned the respect of the JPL engineers. According to Agnese, “They said, ‘When we were in seventh grade or when we were in high school, we were not at all doing what you guys are doing.’ So yeah, they were very impressed.”

Thank you to longtime team mentor and JPL Robotics Systems Engineer Julie Townsend for organizing this invaluable meeting of the minds. 

Next up for the Javabots and the Rock N' Roll Robots? League Meet #3 in January—and, hopefully, Houston in April!