Small Cluster Underwater Robot design with Variable Pitch Propeller

Most underwater robots use multiple sets of thrusters with motors and propellers to drive them independently that makes them bulky, inflexible and complex. In this paper, the propeller is innovatively designed that it can change the pitch that can be applied to underwater robots. The compact design, propeller response speed and high movement flexibility are the biggest advantage of this robot over current conventional designs. The movement of robot is controlled by three propellers and their rotations are driven by a common motor and each propeller is equipped with a servo to control the pitch. Transmission structure designed is symmetrical and compact that creates dynamic balance of the strong structure in itself. The retractable float completes the data transfer between the robot and the ground control also informs space assisted position of the robot when it is underwater and the float is outside of water. In addition, the robot also includes a matching electronic drive and remote control box. Basic movement requirements can be achieved through the independent and coordinated control of the three actuators of the robot. The actual underwater test of the robot verifies the flexibility and horizontal stability of the robot designed. The characteristics of carrying sensors in underwater robots to move more flexibly and effectiveness of the proposed control method is also verified in the actual water test.