Local study asks how fish manage to swim

A team of researchers at King Mongkut's University of Technology Thon Buri has spent five years grappling with the question of how fish have become highly efficient swimmers.

From their findings, the team, led by the university's professor of mechanical engineer, Professor Saroj Saimek, has developed a robot fish that they hope will have a variety of useful applications, once it's perfected.

 When the team began its research, it was mainly interested in how fish generated energy when they were swimming, Saroj explained. As its research has progressed, the team has created three working generations of the robot fish.

"In building the robot, we faced three main problems: the design of the mechanism, water leakage and radio transmission. At this moment, we believe we have fixed 60 per cent of the first two problems. The final problem will need to be solved when we want to go deeper [into the water]," he said.

Saroj said the study would focus on vortexes created by a flywheel while the robot fish was swimming in water and the motion of fish, or interaction between the robot's head and its tail, both of which create vortexes in water.

At present, the team is still developing the third prototype of the robot fish. It is about 90 centimetres long, weighs 7 kilograms and is able to move forwards through 1.5 metres at a top speed of 30 centimetres per second.

"Development of the robot is a first step," Saroj said. "Now we will be able to create and transfer our own data. Our research and development is 60-per-cent complete. It has cost Bt50,000."

The team is planning to develop a fourth-generation robot fish in the near future. It will see the adaption of a water-turbine process into the new robot in order to study the potential energy it is able to generate with its tail while swimming.

Saroj said the team was looking for Bt1 million in funding for future development. It hopes to be able to develop the fourth prototype within three years.

The robot fish will have applications in support of various activities including military surveillance missions, hydro-electric systems and movie productions.