A compliant crank-slider mechanism can be constructed by adding constant-stiffness springs at its joints. Different mounting of springs brings changes in the stiffness performance, which has been analyzed in separated case studies. In this paper, a unified stiffness model is developed for comprehensive analysis of the stiffness performance. With the model, four types of stiffness behaviors, namely hardening, softening, negative stiffness and zero stiffness behaviors, can be simulated with varying parameters. Using the model, stiffness behaviors of the mechanism are analyzed. A new approach constructing constant-torque mechanism is proposed with an example included.
Stiffness behavior compliant crank-slider mechanism unified stiffness model
This is a preview of subscription content, log in to check access.
The research is supported by Innovation Fund Denmark through Grands Solutions project Exo-aider. The first author acknowledges the CSC scholarship for his study at Aalborg University, Denmark. The third and fourth authors acknowledge the support of National Nature Science Foundation of China (Grant nos. 51675018 and 61773042).
Ham, R.V., Vanderborght, B., et al.: MACCEPA, the mechanically adjustable compliance and controllable equilibrium position actuator: design and implementation in a biped robot. Robotics and Autonomous Systems, 55(10):761–768 (2007).CrossRefGoogle Scholar
Zhou, L., Bai, S.: A new approach to design of a lightweight anthropomorphic arm for service applications. Journal of Mechanisms and Robotics, 7(3) 031001, (2015).CrossRefGoogle Scholar
Christensen, S., Bai, S.: Kinematic analysis and design of a novel shoulder exoskeleton using a double parallelogram linkage. Journal of Mechanisms Robotics, 10(4) 041008, (2018).CrossRefGoogle Scholar
Jessica, A., et al.: Control and evaluation of series elastic actuators with nonlinear rubber springs. In: IEEE/RSJ IROS 2015, pp.6563–6568 (2015).Google Scholar
Park, J.J., et al.: Safe joint mechanism based on nonlinear stiffness for safe human-robot collision. In: IEEE ICRA 2008, pp. 2177–2182 (2008).Google Scholar
Wu, T., et al.: Design of an exoskeleton for strengthening the upper limb muscle for overextension injury prevention. Mechanism and Machine Theory, 46(12):1825–1839 (2011).CrossRefGoogle Scholar
Arakelian, V., et al.: Improvement of balancing accuracy of robotic systems: Application to leg orthosis for rehabilitation devices. Mechanism and Machine Theory, 43(5):565–575 (2008).CrossRefGoogle Scholar
Liu, Z., et al.: Design, analysis, and experimental validation of an active constant-force system based on a low-stiffness mechanism. Mechanism and Machine Theory, 130:1–26 (2018).CrossRefGoogle Scholar
Shaw, A.D., et al.: Dynamic analysis of high static low dynamic stiffness vibration isolation mounts. Journal of Sound and Vibration, 332(6):1437–1455 (2013).CrossRefGoogle Scholar
Ibrahim, R.A., et al.: Recent advances in nonlinear passive vibration isolators. Journal of Sound and Vibration, 314(3):371–452 (2008).CrossRefGoogle Scholar
Li, Z., et al.: A novel revolute joint of variable stiffness with reconfigurability. Mechanism and Machine Theory, 133:720–736 (2019).CrossRefGoogle Scholar
Bacek, T., et al.: Design and evaluation of a torque-controllable knee joint actuator with adjustable series compliance and parallel elasticity. Mechanism and Machine Theory, 130:71–85 (2018).CrossRefGoogle Scholar
Yang, Z., et al.: An adjustable gravity-balancing mechanism using planar extension and compression springs. Mechanism and Machine Theory, 92:314–329 (2015).CrossRefGoogle Scholar
Hou, C., et al.: Functional joint mechanisms with constant-torque outputs. Mechanism and Machine Theory, 62:166–181 (2013).CrossRefGoogle Scholar