Design of Sliding Mode Control for Robot Arm Trajectory Tracking Based on Chattering Suppression

With the rapid development of industrial automation, robotic arms, as important automation equipment, are playing an increasingly important role in various fields such as manufacturing, logistics, and healthcare. In the practical application of robotic arms, ensuring their precise and stable movement according to the predetermined trajectory is crucial. However, a major drawback of sliding mode control is the presence of chattering, which can adversely affect the trajectory tracking performance of the robotic arm. Chattering not only causes instability in the movement of the robotic arm but also poses a potential threat to its lifespan and safety. This paper addresses the chattering issue in sliding mode control by proposing a novel control strategy that combines a disturbance observer with a composite reaching law. The main contributions of this work include the construction of a dynamic model for a dual-link robotic arm using the Lagrange function method, designing a disturbance observer to estimate and compensate for external disturbances, and developing a composite reaching law to reduce chattering. The proposed method is validated through simulation experiments, demonstrating its effectiveness in improving trajectory tracking accuracy and stability.