Abstract
Our pseudo-linear variable-lever variable stiffness actuator (PLVL-VSA) allows almost linear torque deflection characteristics in a compact form. However, in its original form, this advantage of the PLVL-VSA comes at a cost of increased stiffness variation torque, which limits the passive deflection range. In this work we propose a modification of our PLVL-VSA to solve this drawback, and thus extend its workspace, i.e., deflection range, while keeping the overall parameters of the actuators and the spring the same. We analyze the effect of the modification in a mathematical model and compare it to the original. The new configuration requires less torque and energy to vary the stiffness. The mechanism is also able to store a lot more elastic energy. As a drawback, the modification both introduces a discrete nonlinearity and reduces the pseudo-linearity of the torque-deflection graph. It also disables the use of very low stiffness setups.
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Dežman, M., Gams, A. (2019). Extending the Workspace of the PLVL-Variable Stiffness Actuator. In: Aspragathos, N., Koustoumpardis, P., Moulianitis, V. (eds) Advances in Service and Industrial Robotics. RAAD 2018. Mechanisms and Machine Science, vol 67. Springer, Cham. https://doi.org/10.1007/978-3-030-00232-9_30
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DOI: https://doi.org/10.1007/978-3-030-00232-9_30
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