For people confined to wheelchairs, the proliferation of ramps has greatly enhanced their mobility. Unfortunately, opening doors remains an omnipresent, and frustrating, challenge. Oddly enough, opening doors also presents a serious impediment for anthropomorphic robots. Now, robotics engineer Erin Rapacki has solved both problems with a single stroke.

Continuing a student project she began at University of Massachusetts, Lowell, Rapacki has created a cheap robot arm that can serve as a door-opening assistant to wheelchair bound humans, or as the primary arm for mobile robots. The trick was finding the right material for the fingers, something hard enough to grasp the handle, but supple enough fit a range of shapes.

Rapacki created the arm to use only one motor, utilizing a slip clutch to allow the arm to twist and push (or pull) at the same time. Altogether, the arm only cost $2,000 to build.

Now if only she could do something about the height of elevator buttons…

New Scientist