Background Research

Underwater robotics has become more popular over the past few years thanks to NURC, a corporation that hosts underwater robotics competitions. They partnered with NASA to create underwater robots. These robots are actually relatively simple compared to a regular robot. A regular robot needs programming and a "brain" to coordinate all of the motors. Underwater robots are connected to their controllers by a physical tether. This serves a few different purposes. First of all, It prevents the robot from becoming impossible to retrieve in the event of a failure. The tether has wires running through it also, which allows for communications between the user and the robot. Wireless signals travel a LOT slower underwater, and are an inadequate means of communications. The tether allows for constant control without any issues. The tether also gets rid of the need for programming or a brain. With wireless communication, a transmitter has to take in all the controller inputs, translate them into radio waves, which is then received by a receiver on the robot. The receiver then has to translate the signals BACK into signals, which have to be appropriately distributed to each motor. The tether is used to complete a simple circuit, where when the switch is pushed, current will be allowed to the motor. Underwater robots also have different physical aspects that you need to keep in mind when you are building one. If the robot is filled with too much air, it will have a hard time diving. It's the same with the opposite, where the robot is too heavy to come back to the surface. You also need to keep in mind that these robots are underwater, and water and electronics DO NOT go well together. If a wire is stripped, you could short out your entire robot. Motors also have to be enclosed in a case filled with a waxy, waterproof substance. It should also maintain a good balance, or it could capsize, and make it extremely difficult to maneuver.