Triage

What's this thing?

I came into StarkHacks to get my hands dirty with something I'd never touched before: physical robotic mechanisms. Ford's gripper challenge gripped my attention because the problem is odd to me. Most industrial grippers are rigid, and the parts they're asked to handle aren't. Wire harnesses, ball bearings, and deformable parts are where a usual two-jaw gripper starts to lose its grip, it's optimized for repeatable picks on known shapes, not for anything irregular or soft. I wanted to build something that handles that a bit more the way a human hand does. After all, why need to reinvent the wheel.

My prototype is a 3-finger gripper, but the full TRIAGE concept is a 6-finger modular system with room for multimodal sensing later on. The idea was to explore a more adaptable grasping architecture with the fingers as the first step.

Human fingers don't have motors inside them. Tendons pull from farther back, an opposing muscle group pulls the other way, and the finger itself is mostly a passive structure responding to those forces from elsewhere.

How I built it

The core idea was biomimicry: don't reinvent the wheel, just copy the one that already rolls. A tendon pulls the finger closed, an opposing force brings it back open. I mocked that up with string as the tendon and a pen spring for the return force, the same job your extensor tendons do when you straighten your fingers out.

An Arduino Nano and motor driver drives the actuation, controlling when the string pulls and releases. The result is a finger that can open and close in a way that loosely mirrors biological motion, which was the whole point of the prototype.

Challenges

Translating biology into hardware is sticky. Your fingers feel effortless until you actually try to replicate them. Pushing and pulling springs and strings to balance so the finger returns cleanly to a neutral took an amount of fiddling for something that your hand does a few hundred times a day without thinking about it.

Built With

• 3dprinting
• arduino
• c++
• cad
• circuit
• onshape
• solidworks/cad-tool-you-used