Disturbance Observer-Based Trajectory Tracking Control for Nonholonomic Wheeled Mobile Robot Subject to Saturated Velocity Constraint

• Published in: Applied artificial intelligence Vol. 28; no. 8; pp. 751 - 765
• Main Authors: Yue, Ming, Wu, Guoqiang, Wang, Shuang, An, Cong
• Format: Journal Article
• Language: English
• Published: Philadelphia Taylor & Francis 14.09.2014; Taylor & Francis Ltd
• Subjects: Closed loop systems; Control theory; Controllers; Disturbances; Estimates; Mathematical functions; Robotics; Robots; Simulation; Sliding mode; Tracking control; Tracking control systems; Trajectories; Vibration
• ISSN: 0883-9514; 1087-6545
• DOI: 10.1080/08839514.2014.952918

The problem of trajectory tracking control for a nonholonomic mobile robot is discussed in this study, in which both the dynamic behaviors of disturbance adaptability and the velocity saturation constraint are considered simultaneously. To realize this objective, a double closed-loop control structure is presented. On the outer loop, an improved velocity saturated controller based on hyperbolic tangent function is established; on the inner loop, an integral sliding mode controller, which possesses a fast transient response property with less steady-state error, is developed. In addition, to alleviate the inherent chattering behavior of sliding mode technology and enhance the external disturbance adaptability, an adaptive scheme as a disturbance observer is adopted by which one could estimate the uncertain disturbance acting on the mobile wheels rapidly. Simulation results verify the effectiveness of the proposed control theories.