Robots played a key role in assessing damage and radiation levels at the Fukushima nuclear power plant, crippled by the massive earthquake and tsunami that struck Japan more than a year ago. But so far all the robots relied on tracks to navigate inside the reactors, in addition to aerial vehicles used to observe the site from above. None of the robots had legs. Now Toshiba is about to change that. The company announced yesterday that it plans to send a quadruped robot to the disaster site. Is this Japan's answer to BigDog?
The remote-controlled, radiation-resistant quadruped has multiple cameras and carries a dosimeter. Its legs are powered by electric motors (unlike BigDog and HyQ, two quadrupeds that use hydraulics). One news outlet said the robot resembled a "headless dog." Another described the robot as "an ice cooler on wobbly metal legs." Well, I sure would love to have a robotic ice cooler like that. From the photo above, it's a cool-looking machine. But reports of the robot's first demonstration were less impressive. The robot slowly climbed a flight of just eight steps, taking about a minute to go up each step. And at one point, the robot stalled, and Toshiba engineers had to pick it up and reboot it. The company said the robot has also "a folding arm that can release a companion smaller robot," but details about that capability are scarce.
The Fukushima site and its surroundings are still highly contaminated, so it makes sense to send in more robots. But does it make sense to use a legged robot? From a research point of view, testing a new platform in a real environment could provide valuable insight. Some roboticists have long argued that legged machines could perform better than wheeled or tracked ones on difficult terrain. On the other hand, it's hard to see how the Toshiba quadruped, which from what we know is a prototype completed not long ago, could outperform an iRobot PackBot or Warrior, with years of real-world operation, or, for that matter, the Japanese ground robot Quince, which has a capable multi-track system. But let's not underestimate the Toshiba robo-dog. We look forward to seeing the company set it loose at the site. And then we'll be able to determine the winner: tracks or legs?
Here are the specs from Toshiba:
Size: 624mm (L) x 587mm (W) x 1066mm (H)
Power Source: Battery
Battery time: 2 hours (continuous use)
Weight Capacity: 20kg
Walking Speed: 1km/h
Operation: Wireless remote control