You Built What?!: A Remote-Controlled Robo-Arm

Smart Arm Mike Basher

Two summers ago, Easton LaChappelle thought it would be fun to build a robotic arm controlled wirelessly using a glove. LaChappelle, then 14, knew nothing about electronics, programming, or robots—but he was bored and desperate for a challenge. So over the next couple of years, the teen, now a high school junior, toiled in his cramped bedroom workshop in Mancos, Colorado, ironing out the details. In time, he emerged with a robo-arm operated by a gaming glove—and his mind.

LaChappelle began his bionic quest by scouring online forums and tutorials to glean as much know-how as he could about sensors, motors, and coding. His first model won him third place at the state science fair in 2011, but its fingers, made of flimsy electrical tubing, could not grasp anything heavy.

Unsatisfied, LaChappelle started over. He designed a new hand with computer modeling software, and then asked MakerBot Industries in Brooklyn, New York, to print the plastic “bones.” The new hand had human-like digits with multiple joints and a thumb that could bend inwards. Small electric motors in the wrist could curl the fingers by pulling a piece of ligament-like fishing line through each digit to its fingertip.

But the stretchy fishing line loosened up over time. LaChappelle’s mother, a former jeweler, suggested using nylon-coated steel wire instead. The wire could close the fingers but proved too rigid to recoil them, so LaChappelle rigged tiny dental rubber bands leftover from his awkward, brace-faced years into faux tendons for the joints. “The rubber bands provide a kind of spring-back mechanism,” he explains.

To control his robo-limb, LaChappelle modified a 1980s-era Nintendo Power Glove to convert real hand movements into robotic motion. Next, he made a brain-based controller by hacking parts of a headset from the board game Mindflex, which can read a player’s brainwaves. Simply by concentrating, LaChappelle says he can open and close the robo-hand.

The glove-based system earned him second place at an international science fair in 2012, and his parents rewarded him with his own 3-D printer, now housed in his bedroom closet. For his next goal, LaChappelle plans to evolve the current robo-arm into an inexpensive yet highly capable prosthetic. “I’m going to keep going and trying to make it better and better,” he says.

See how it works on the next page.