Attitude Balance Control of a Wheeled Quadruped Robot Utilizing an Inertial Measurement Unit

The Wheeled Quadruped Robot (WQR), a novel hybrid mobile platform that combines the advantages of wheeled and legged locomotion, has attracted significant research interest due to its enhanced mobility and stability in complex terrains. However, achieving efficient attitude stabilization during dynamic operations remains a critical technical challenge. This study initiates with a thorough kinematic modeling of the WQR mechanism. Next, we present a novel attitude stabilization methodology employing closed-loop control architecture driven by real-time Inertial Measurement Unit (IMU) data streams. Our approach integrates kinematic constraints and real-time IMU data with Proportional-Integral (PI) regulators to establish an inverse kinematics-guided adaptive adjustment mechanism. This mechanism dynamically adjusts leg movements in response to deviations in attitude. To assess the effectiveness of our control strategy under diverse terrain conditions and motion patterns, extensive simulations were conducted, comparing it with fixed joint angle control and traditional inverse kinematics-based control methods. The simulation results indicate that the WQR's attitude stability is markedly improved across various terrains and motion states after implementing our proposed control strategy. This research contributes to robotic control theory by innovatively integrating sensor fusion and adaptive kinematics, thereby significantly impacting the development of robust mobile platforms for unstructured environments.