As robots get larger, smarter, faster, stronger and more agile, there's good reason for humanity to be a little worried about the day they eventually turn on us. Unless all robots end up like UCLA's BALLU, which is really nothing more than a pair of skinny robot legs attached to a helium balloon.
BALLU — which stands for Buoyancy Assisted Lightweight Legged Unit — is the brainchild of Dennis Hong, who works out of UCLA's Robotics & Mechanisms Laboratory. Realising that the biggest challenge for a bipedal robot was still the constant pull of gravity, Hong wanted to experiment with a bot that wasn't always at risk of falling over and breaking.
BALLU's helium-filled mylar torso isn't completely weightless, it does rely on its legs to remain upright. But it's so incredibly light its legs are almost twig-like, with basic cable-driven knees allowing it to walk forward, backward and left or right. It's remarkably stable on its feet as a result of its balloon body, and it can even walk across water without sinking and frying all of its electronics.
A robot that can be defeated with a couple of safety pins and pruning shears should give humanity a sigh of relief about the future, but what good would a bot like BALLU be in terms of practical functionality? A larger balloon torso would give it enough lift to carry sensors or other simple tools into areas too dangerous for humans to tread. And its creators are already working on a quadruped version with more lifting and load capacity. One day you could have a deflated robot stashed away in your glove box to help with emergencies — as long as they don't involve a cactus or anything pointy.