That machine is XoMotion, a self-balancing exoskeleton built to help people with mobility impairments stand and walk with their hands free. The device Peykari set out to build would balance itself. "It is a humanoid system that can walk on its own," he says, "and now we have a human inside it." So Peykari is moving the work toward artificial intelligence, and he is blunt that there is no alternative. One machine carries a person inside it.