Undergraduate students from the Department of Mechanical and Process Engineering (D-MAVT) have once again given their all and in late May will be presenting 11 new projects developed over the past year. ETH News takes a closer look at two of them.
The Sepios underwater robot is similar to the squid or cuttlefish in many ways. (Photo: iStockphoto / collage)
In the fifth and sixth semesters, undergraduate students de￼epen their overall skills base and set a focus. What sounds like the humdrum quotidian life of a student culminates for the future mechanical engineers in a highly regarded and popular educational event. Each year they present their focus projects and this year's results are particularly prolific: Eleven groups will demonstrate new robots, motors, turbines and other developments.
Sepios loops the loop
The combination of robotics and bionics is tempting for any engineer. So it’s no wonder that Martin Möller, project coordinator of Sepios, quickly found eight colleagues who were willing to work together to build an underwater robot that mimics the movements of cuttlefish and squid. Sepios’ hull comprises a polycarbonate cylinder that houses the control electronics and batteries. Up to four modular fins can be attached and removed from the cylinder as needed.
Small rods along each fin move an elastic foil in a wave-like undulating motion, enabling Sepios to move gracefullythrough the water. The robot swims – as is typical for its role model, the cuttlefish – equally well backwards and forwards, and can rapidly decelerate and accelerate in the other direction. Each dive teaches the students more and Sepios is now capable of doing loops and twists in the water.
Since it is so agile, in future the underwater robot should be able to navigate through narrow pipes and openings, and as it does not have a propeller it is less likely to get caught in seaweed or disturb sensitive animals. For now, Sepios can dive to a maximum depth of only five metres in the pool, but the construction of a more robust prototype is feasible. Its builders are well aware of the potential of Sepios, but they are, first and foremost, enthusiastic students: “For now, Sepios is a research project,” says Möller. “It's a long way from becoming a commercial product.” Some day, Sepios could potentially be used to investigate shipwrecks and underwater caves, film sea creatures or serve as a diving assistant in offshore applications.