Design and implementation of a modular body for an underwater robot

Abstract

In the context of underwater robotics, most vehicles currently deployed use a propulsion system based on propellers. Propellers are very efficient but they tend to be noisy and fragile, in particular, in cluttered environment. Webbed legs are used by animals such as freshwater turtles so they may be a viable alternative to propellers. This project is part of a larger study that may lead to the development of an underwater robot using web feet propulsion in similar fashion as sea‐turtle or even freshwater‐turtle. First of all, a mechanism working with 3 degrees of freedom should be designed in order to generate the movement of the webbed legs. Different mechanisms have been proposed and studied in terms of energy, compactness, sealing, durability… At the end, a discussion between them is done using a decision matrix to decide which one is the best alternative to implement. The second aim of the project is to study the body of the robot like modules, separate exchangeable parts dedicated to sensors, actuators, electronics or power. Modules with similar functions should be designed following these requirements: capability to support pressure at depth up to 10m, mechanical connection of the modules and sealing.