Many of the best engineering ideas take inspiration from nature. Shaastra’s featured projects in the past included robots that were based on animal adaptations, like the Ornithopter, an unmanned flier that flew by flapping its wings like a bird. This year, at the Centre For Innovation, the concept  has been taken further in a design that will have a great scope of potential use. Robotic fishes would have the ability to conduct underwater exploration in ways that are impossible for humans, or even conventional unmanned submersibles to do. Schools of mini robofish could be used to detect pollution or inspect underwater structures such as sunken boats and submerged oil pipes. As a result of their small size, they would also be economical and easy to handle.

The main challenge involved  in this robot is the fish’s complicated tail motion, which the team intends to accomplish by using a single servo. The tail is made of blocks connected by links, designed such that controlling just one of them creates a natural tail motion. The whole structure down to the lengths of the links involved  was designed with the help of computer simulation. The video below shows how the tail mechanism works:

All the circuitry required for this bot to function is housed inside a water-proof compartment in its head, and the body was made in a casing of acrylic. RoboFish will be designed detect obstacles and avoid them by taking turns, and ultrasonic sensors have already been tested for usability. Added buoyancy and stability will be given to this structure by using thermocol. The finished bot is expected to be a small,  light and manoeuverable device.