Anti-disturbance Control of Vertical Pitch Attitude of Underwater Spherical Robot

Spherical underwater robots play an important role in underwater image acquisition, and are widely used in military and scientific investigations. The spherical underwater robot needs to perform heave motion when working in water, and pitch attitude adjustment is the key. When the spherical underwater robot adjusts its underwater pitch attitude, due to the influence of the internal pendulum structure and water flow, there is a phenomenon that the pitch angle fluctuates. This article starts with the structure, conducts kinematics and dynamics analysis, establishes the robot dynamics model based on Newton's Euler formula, compared with the traditional PID control, the anti-interference ability is not strong, and then designs the exponential approach law sliding mode control The robot achieves stable control of the robot's pitch attitude. Experiments show that the exponential approach law sliding mode control method can effectively control the robot's pitch angle in complex underwater environments.