Disturbance Observer-Based Variable Structure Control on the Working Attitude Balance Mechanism of Underwater Robot

When an underwater robot is to work under the water, the manipulator has to reach out. This can change the center of the gravity and cause the robot pitching. Itpsilas difficult to make a maneuver for a pitched robot. An automechanism was developed to balance the pose of the robot. A sliding mode variable structure controller was designed to control the balance device, in which a disturbance observer was used to observe the disturbances. This reduced the switching-gain of the control system greatly and weakened the chattering more of course. A practical result was achieved for the control of pitch change of the robot caused by the manipulators and detecting pan/tilt and indicated the practicability of the balance device including its control approach. As the device is a single-axis system, a double-axes system is needed for the balance of pitching and rolling.