On an adjustable-stiffness spring composed of two antagonistic pairs of nonlinear leaf springs working in post-buckling

摘要

We consider the prototype of adjustable-stiffness spring recently developed by some of the authors of this note, and published in Mechanism and Machine Theory, Vol. 46: pp. 1970-1979, 2011. The elastic device is an antagonistic setup consisting of two pairs of non-linear leaf springs working in bending, simultaneously and in opposition, and undergoing large displacements. In this work, the case of both pairs of leaf springs working in post-buckling conditions is studied. To this purpose, a mathematical model is proposed in order to predict the mechanical behavior of one leaf spring. Also, a prototype of one leaf spring is fabricated and tested, showing excellent agreement with the numerical results derived from our model. Finally, the force-displacement curves of the new spring are obtained and compared with the ones of the previous case.