Building for the competition, not just the demo
The brief from Mass Robotics Form & Function was straightforward and unforgiving: build a functioning arm that could actually pick a tomato in front of a judging panel, not just move convincingly on a bench. That meant every joint and bracket had to hold up to repeated cycles, and the end effector had to handle a soft, easily-bruised target without crushing it.
Machining the arm
My role centered on turning the arm's aluminum components on a CNC lathe — the load-bearing links and joint housings that make up the arm's structure. Machined parts hold tolerance and repeat cleanly across cycles in a way that 3D-printed brackets don't, which mattered once the arm was running the same reach-grasp-retract sequence dozens of times in front of judges.
Designing the end effector
For the gripper itself, I designed a fin-ray end effector in Fusion 360 — the same compliant-mechanism approach used on the standalone gripper project, adapted here to close gently around fruit without bruising it. That's the advantage of a passively-conforming finger over a rigid pinch: the arm doesn't need precise force control at the gripper to handle a delicate object safely.
Assembly and result
I assembled the completed arm ahead of the Mass Robotics Form & Function competition, where the team took 1st place along with the Audience Appreciation Award — recognition that the arm didn't just work, it was compelling to watch work.