This robot was a group project built in the class fundamentals of robotics. This Turtle inspired robot autonomously swims across a pool. When it detects a wall, it turns. The robot is powered by a bilge pump that expels water out the back providing thrust. A pair of servo controlled flippers steer the turtle.
To build this robot, I first constructed a virtual model in solid works. Using simulation tools, I was able to shape the hull and distribute internal ballast so the turtle is balanced and has a stable waterline. Because the hull and shell were made of light styrofoam, multiple steel blocks were added to achieve a stable waterline.
The turtle’s shell and hull were made using a CNC router. I hand carved the flippers, hat and head. I coated the pieces in epoxy then painted them with acrylic paints and multiple layers of shellac.
The electronics are housed in a water tight plastic box. The sensing and processing is very simple. Two IR sensors on the front of the turtle sense the wall and an onboard arduino controls the robot. This Turtle performed swimmingly when we demoed it. It performed so well it was a bit boring and anticlimactic. It did what it needed to do without fault.