Climbing to the Top: Inside Caltech's 41st Annual ME 72 Student Engineering Competition
Cheers echoed through Caltech's Scott Brown Gym as a 20-pound student-built robot powered its way up a steel-plated pyramid and crested the summit. Moments later, the machine accurately deposited its payload of pellets, drawing another round of applause from the crowd gathered for the 41st annual ME 72 Engineering Design Competition.
Every year, third- and fourth-year mechanical and civil engineering undergraduate students take ME 72, a two-term, project-based course that culminates in the engineering design competition. The details of the challenge vary annually. In previous years, student teams engineered robots to compete in bot hockey and designed blimps that played "airship quadball."
"Every mechanical engineering program in the country has to have a capstone project. The ME 72 project is the engineering design capstone requirement at Caltech, so it's a very big deal for the students," says Michael Mello (PhD '12), the ME 72 course instructor and teaching professor of mechanical and civil engineering.
This year, students faced a challenge called "Apex Cleanup: Summit, Mint, Bank." At the center of the 40-foot by 40-foot field was a 4-foot-tall, steel-skinned pyramid with faces sloped at 37 degrees. Each team's robots had to scale the pyramid, crest the summit, and perform maneuvers on a narrow platform, demanding careful attention to traction, stability, control, and integrated system design.
Six teams, made up of five to seven students, each built two robots over the course of about 15 weeks. The students engineered and manufactured their robots in the Jim Hall Design and Prototyping Lab, located in the subbasement of the Eudora Hull Spalding Laboratory of Engineering, under the guidance and supervision of ME 72 co-instructor Paul Stovall and lab machining assistant Trent Wilson. Meanwhile, teaching assistants who had previously participated in ME 72 served as experienced peer mentors throughout the course. Leading up to competition day, the teams gathered in the subbasement at all hours to test and refine the robots.
According to fourth-year student Anya Mischel, each phase of the project challenged her team, the Pharaobots, in different ways. At the beginning, she says, "We all worked on different parts of the robot for the bulk of the project, like the drivetrain or intake. Every individual subassembly seemed to work well on its own, but we had a lot of difficulties getting everything to integrate smoothly."
That challenge of integrating individual contributions into a cohesive whole is the kind of collaborative learning the ME 72 course is designed to foster.
"It is such a wonderful proxy for industry experience," Mello says. "The students get the rigors of working with a group of people with different strengths and weaknesses for the first time in their life—having to learn the importance of communication, miscommunication, and how to handle mistakes as a group. Seeing them work through these things—that's growth that I value as much as the technical aspect of them creating a robot capable of climbing the pyramid and building a cool, efficient intake."
On March 10, the student teams arrived long before the 11 a.m. competition start time for final test runs. At their worktables, the students stayed busy with last-minute adjustments and troubleshooting. The steady whir of motors and the clatter of tools filled the gym, and every so often students glanced across the arena to watch a rival robot testing its movement on the field.
The tournament comprised a series of ten round-robin-style matches, where three teams met on the field for face-offs that lasted four and a half minutes. This year's teams—Big Red, The Clanks, Pharaobots, Pyramaniacs, Climb & Punishment, and MechE Wednesday: After Party—strategized the best way to score points. Summiting the pyramid and depositing pellets into it offered the highest scoring return. However, this approach came with added risk: Repeated climbs placed significant strain on the robots' traction, motors, and control systems.
Resilience was the theme of the day. As part of milestone tests before the competition, teams had to prove their robots' capability in single tasks, such as climbing the pyramid and intaking pellets. Then, during competition matches, robots endured sustained pressure, sometimes competing in back-to-back rounds. In between matches, the students worked urgently along the sidelines to repair and adjust their robots as the tournament progressed and as the robots inevitably took damage.
After the initial ten matches, four teams—The Clanks, Pyramaniacs, MechE Wednesday: After Party, and Pharaobots—made it to the semi-finals. Pharaobots became one of the top teams to watch. Leading up to the competition, the team spoke openly about their nerves, but once matches began, their robots proved remarkably consistent by climbing reliably and scoring in successive rounds.
In the final match, Pharaobots secured the win against Pyramaniacs, earning the chance to lift the ME 72 gear-shaped trophy, a long-standing symbol of victory in the competition.
Ana Jaramillo, a third-year undergraduate and a member of Pharaobots, remotely controlled one of the robots during matches. After the competition, she says, "From seeing the competitions in past years, I knew this was definitely going to be fun. Maybe I'm biased, but this challenge was more fun to me than the past years' because it was more abstract, different, and challenging."
Mischel, who earlier reflected on the challenges of integrating the robot's many components, says, "I learned so much. I don't think I've learned more from anything at Caltech. Coming out of the competition, I feel like we made almost every possible mistake throughout the process. Still, from those mistakes and trying to fix them constantly––improving the design and adjusting in retrospect––we just learned so much."
