This Arduino-powered robotic fish swims like the real thing
Biomimicry is often used to take the designs that nature has perfected over a period of millions of years and incorporate them into our own technology. One maker who goes by mcp on YouTube took this idea one step further and created a fish that can swim in the water like the actual creature. By carefully analyzing and studying the patterns a fish makes while it scurries through a lake, he was able to reduce these motions down to just a few joints.
The body of this DIY robotic fish was constructed from a series of four joints that each contain a single mini servo motor to control their movements. Next, an Arduino Nano was selected as the microcontroller board due to its small size and ample amounts of GPIO pins. In order for the fish to sense if there is an obstacle in the way and avoid it, the device also features “eyes” that utilize IR emitter/receiver pairs.
Once the spine of servo motors was combined with the Arduino and a set of LiPo batteries, mcp slipped over a skin made from a waterproof latex-like material that aids in moving throughout the water. In his video below, the DIY robotic fish can be seen oscillating freely through a bathtub full of water, along with a pool. His device works very well as it generates plenty of forward force to swim wherever it wants while avoiding obstacles.