After the Nuclear disaster triggered after the Tsunami in Fukushima Daiichi nuclear Power plant in Japan, Some countries have vowed to shift towards safer alternatives of energy while many countries of world as busy reinspecting the safety of its Nuclear power plants. Even in US, a year long study has shown that around one third of Nuclear power plants accidentally leak Nuclear waste in to the water used for cooling the plant. Sensing an urgent need to find safe and economical way to inspect the water pipelines researchers at MIT’s d’Arbeloff Laboratory for Information Systems and Technology have designed an egg sized Robot which can withstand the intense radiation in pipe and give a correct picture of any defects in water circulating system.
Spherical robot as developed by Harry Asada. Image credit: Harry Asada/d'Arbeloff Laboratory
The robot was designed under the guidance of Harry Asada, the Ford Professor of Engineering in the Department of Mechanical Engineering and director of MIT’s d’Arbeloff Laboratory for Information Systems and Technology. The major defect for which it is designed is the corrosion due to flowing fluid (water). It is also difficult to detect leakages. The conventional practices involve usage of indirect techniques like ultrasonic waves and another as detecting voltage difference due corrosion and leakages. Direct detection methods like visual inspection although more effective; is generally avoided. The reason being, it involves digging up of pipes and manually inspecting them. This is both a time intensive and a capital intensive operation.
The robot is designed in a very innovative fashion, quite different from conventional autonomous underwater vehicles (AUVs). The robot is not provided with any rudders or any external mechanism to make its way through water. Instead, it is provided with a specially designed internal valve systems. The robot depends on flow velocity of water liquid for its navigation. The valve designed in the shape of English alphabet Y helps the researchers maneuver the machine. The direction is changed by closing and opening a valve. When water is discharged through one valve it forces water in that direction. The robot moves in opposite direction. This mechanism works on Newton's third law of motion. The designers have purposefully eliminated using rudders because, there is always a possibility of them getting stuck in some tight spot, failing to remove which would result in closing power plant completely for some time.
After a thorough research, the robot has evolved from the original idea. Asada earlier planned to have the robot capture images first and to get those once the robot is out of the pipe channels. However, the robot is now equipped with wireless technology which can instantaneously transmit images up to a distance of 100m. Moreover, the camera can also have a zooming effect which helps to focus on a doubtful part of pipe. The camera installed on this egg sized machine and can function in extremely radioactive environment for quite a long time. The robot is an economical investment as it can make several trips in the widely spread pipe network.
Such types of robots although a new concept can prove beneficial in long term. It can also be used for city sewage system and inspecting underground water system. The robot involves simple technology and being designed considering an economical aspect, most cities can afford it to be used on a regular basis. The egg sized robot, once commercial will be useful in civic life too.