Adaptive Stiffness Control for Series Elastic Actuators in Robotic Systems Using Dynamic Systems

ABSTRACT In traditional control methods, Series Elastic Actuator (SEA) joint manipulators are limited by their hardware and can only perform tasks with low stiffness requirements. To address this issue, we propose a stiffness adjustment control strategy for SEA manipulators based on Dynamic Systems (DS) with an adaptive stiffness control strategy, which could achieve higher manipulator end stiffness comprehensively considering the overall orientation of the manipulator and control gains. By incorporating a rotation matrix with the Dynamic Movement Primitives (DMPs) method, we enhanced the generalization capability of DS in complex tasks. Compared to traditional DS‐based control strategies, the control strategy proposed in this paper has achieved better control effects in the experiments on the SEA manipulator, and adaptively adjusts the interaction stiffness under different postures to achieve the task goals. Furthermore, experiments on the mobile manipulator have also verified the universality of the control strategy proposed in this paper.