Abstract
This paper discusses on a buoyancy and depth control module for underwater or amphibious robot. The buoyancy control applies recirculating compressed air ballast mechanism that consists of a cylinder, an external bladder called air bag and hoses. An air pump and a valve are installed in the cylinder. The system can manipulate the volume of the air bag by using the air inside of the cylinder to fill the air bag, thus to change the buoyancy force of the system. Then, pressure depth sensing method is used for depth controlling. This method uses pressure sensor to detect ambient pressure of a robot in the water and calculates its current depth. This buoyancy and depth control module will help robot to move up and down and provide depth control during underwater mission.
