Exoskeletons: My friend with a robot skeleton

Daniel Fukuchi and I are walking down a basement corridor with white cinderblock walls and glaring fluorescent lights overhead. He's a little slower, but to be fair, he's partially paralysed from the waist down.
Usually, he can hobble along with crutches for a few feet before losing steam. But today, he's moving at a decent clip, putting one foot in front of the other, straight down the long hallway. The source of his newfound power? An exoskeleton.
The device straps to his waist and thighs, and is powered by two motors at the hips that drive his legs forward. The motion is smooth, and the machine hums with every step. Fzzp. Fzzp.
Every week for the past year, Daniel has been coming to this nondescript basement lab at the University of California, Berkeley, where he's helping to test an exoskeleton designed to put paraplegics back on their feet. "It seemed like it could be something that could potentially help me," he says. "But at the bare minimum, it'd be just kind of fun to play in a robot."