Improved Sliding Mode Active Disturbance Rejection Control of an Auxiliary Robotic Arm for Puncture Robots

ABSTRACT The research on disturbance rejection control for robotic arms in assisted puncture surgery systems aims to improve the precision of puncture surgeries. In this article, an improved sliding mode control (SMC) strategy for robotic arm with active disturbance rejection capability for assisted puncture surgery is proposed. First, a nonlinear extended state observer (NESO) is introduced to detect unknown disturbances based on the state space of the robotic arm. Next, a performance function is established to constrain tracking errors, and a sliding mode surface is constructed based on the constraint function. In addition, an SMC is designed based on the NESO, and an improved sign function is proposed to minimize system chattering. A comparison with other SMCs demonstrates the robustness of the performance function‐based sliding mode active disturbance rejection control (SMADRC) proposed in this article. Finally, the proposed controller is tested with a 6DOF robotic arm, demonstrating accurate joint angle tracking and effective disturbance detection. The average joint angle tracking root‐mean‐square error (RMSE) is for the 2DOF arm and for the 6DOF arm. These results further validate the adaptability and accuracy of the control method described in this article.