Why does a robot take time to arrive at the scene?
Applying Robots to the Nuclear Disaster Scene
Hajime Asama, Professor, The University of Tokyo
Discussion continues on how to apply domestic and international robotic techniques to the disaster at the nuclear power plants. The technology in part has already been applied in the form of the unmanned operation by construction machines.
Immediate application of robots is hoped to reduce radioactive exposure of the workers. Rough-and-ready manner and unpreparedness would necessarily lead to great danger and risk. For instance, a robot can neither reach to its destination nor accomplish its mission, it may become out of operation, obstruct human operation, damage other systems, and so on. Before we actually throw in robots into the scene, the following points must be taken into careful considerations:
- Tasks of robots must be determined. Matching of the task and the function of a robot is necessary since an each robot has a distinctive function. In some cases, reinforcement and remodeling are required.
- The environments for robots to work must be identified. The environmental conditions such as the size of space, lighting and so on constrain the performance of robots. It must be confirmed whether a robot can work in the environments by precisely obtaining information such as various obstacles including wreckage.
- Especially, we have to consider the dose of radiation. If we introduce robots in a rough-and-ready manner, a robot may come to a halt due to radiation. The robot then would become an obstacle for other missions. A robot needs to monitor the total dose of radiation while it is in the mission. We also need to make a good estimation in advance of the level of dose under which the robot may start malfunction, and to plan a mission within the level. The important matters to be discussed include accessing from the low dose-rate area and minimizing the time of mission.
- The competition of resources must be resolved. Concerning the space, multiple robots cannot simultaneously operate in the same space. Concerning the frequency band, those for robot communication must not interfere with those for the other systems. If there are any resource competition, the resource should be time-shared by mission planning.
- Setting up the environments is also a necessary preparation. In the case of tele-operation, the operation room should be located at a safe sites. Routing power and communication wires are also a problem to be solved. If batteries are used, we need to determine how to charge them. We must prepare the area of robots’ evacuation and decontamination to avoid severe radioactive exposure.
- Training the operation is another issue to address since robotics researchers are not able to operate on site. The skill of tele-operation must be well trained using the simulated environments and the robots, before applying them to the real site.