Design and Analysis of a 2-DOF Actuator with Variable Stiffness Based on Leaf Springs

Abstract Variable Stiffness Actuator (VSA) is the core mechanism to achieve physical human–robot interaction, which an inevitable development trend in robotic. The existing variable stiffness actuators are basically single degree-of-freedom (DOF) rotating joints, achieving multi-DOF motion by cascades and resulting complex robot body structures. In this paper, integrated 2-DOF actuator with proposed, could be used for bionic wrist joints or shoulder joints. coupling one universal joint, different from way of DOF cascade. Based on orthogonal generated spherical parallel mechanism, adjusted varying effective length springs, uniformly distributed unit. principle, model design, theoretical analysis VSA discussed work. independence adjusting equilibrium position validated experiments. results show that measured characteristics sufficiently matched values. future, biped robotic arm, ensuring safety interaction.