The optical fiber-type robot for exploration (front) and the POE cable-type robot for exploration (back)
The optical fiber-type robot for exploration (front) and the POE cable-type robot for exploration (back)
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A Japanese research team developed a rescue robot for exploring restricted areas, expecting it to be used for the accident at Fukushima's first nuclear reactor.

The team consists of researchers at International Rescue System Institute (IRS), Chiba Institute of Technology, Tohoku University, Japan's National Institute of Information and Communications Technology (NICT), Japan's National Institute of Advanced Industrial Science and Technology (AIST) and New Energy and Industrial Technology Development Organization (NEDO). The team is now ready to provide the robot, "Quince," on request, it said.

The Quince was developed by making improvements to a robot that has been developed by IRS, etc. It is unclear whether the robot can actually be used for the nuclear accident because there is not enough information about the amount of radiation and situations inside buildings. However, some improvements were made so that the robot can explore the insides of buildings while being remotely controlled from a distance of 2km.

Other improvements that were made based on the advice of experts on space robots enabled to reduce the influence of radiation on the robot. The Quince originally features an excellent mobility for moving through debris and going up and down stairs. And it can be mounted with a thermography device, radiation counter, 3D scanner and camera capable of panning, tilting and zooming. The travel unit of the robot, which is located at the bottom, is waterproof.

To control the robot from a distance of 2km, the research team came up with two methods. The first method is to use two robots. One is stationed at the entrance of a building as a "relay robot" for communicating with the other exploring the inside of the building via an optical fiber.

The relay robot is equipped with a radio transceiver with an output as high as 1W with permission of Japan's Ministry of Internal Affairs and Communications. An operator communicates with the robot for exploration via the relay robot. The optical fiber is made of resin and can withstand a tension of up to 600N. Its length is 200m.

The second method is to combine (1) a portable relay pallet equipped with a large-capacity battery and a radio transceiver and (2) a robot for exploring the inside of a building. The radio transceiver used for the second method is the same as used for the first method. But, for communication between the relay pallet and the robot, a POE (Power over Ethernet) cable capable of transmitting 25W of electricity is used.

The Quince can continuously operate for about two hours when it keeps traveling and six hours when it operates at a fixed point. However, it can be used for longer hours by using the relay pallet for supplying power.

As for the efforts to reduce the influence of radiation, the camera of the robot is covered with a 1mm-thick lead plate except for its lens because the life of its image sensor is considered to be shorter under the influence of radiation. Also, pictures are taken via a mirror. However, some additional measures might have to be taken depending on the situation of the polluted area.