Novel Variable Stiffness Actuator Based on Folded Serial Leaf Springs

doi:10.3901/JME.2017.17.070

Abstract

Abstract: Variable stiffness actuators can significantly improve the dynamic performance of robots and ensure safety in human robot interaction. An overview of different principles working on most structure controlled variable stiffness mechanisms is presented. The design of a novel variable stiffness actuator and its working principle is described. Considering the gap between leaves and rollers in the real mechanism, the analytical joint stiffness model is modified to get a more accurate estimation of the prototype. Experiments are conducted to validate the model and the feasibility of the design. The application of folded serial leaf springs leads to an increased stiffness range while the size and load capacity remains unchanged. Motion synchronization of rollers and the decoupling of joint motion and stiffness adjustment are easily achieved by the parallel assembling of leaves.

Key words: compliant joint, leaf spring, stiffness model, variable stiffness actuator

CLC Number:

TP242

LIU Chang, BI Shusheng, ZHAO Hongzhe, ZHOU Xiaodong. Novel Variable Stiffness Actuator Based on Folded Serial Leaf Springs[J]. Journal of Mechanical Engineering, 2017, 53(17): 70-77.

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