This letter presents a novel rotational variable stiffness joint that relies on one motor and a set of variable stiffness springs. The variable stiffness springs are leaf springs with a layered design, i.e., an electro-active layer of electrospun aligned nanofibers of poly(vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene) [P(VDF-TrFE-CTFE)] surrounded by two electrodes of aluminum and held together by inactive material. To achieve a variable stiffness, different voltages and, therefore, different electric fields, are applied to the springs. The variable stiffness springs are electromechanically analyzed to highlight the voltage-deflection and force-deflection characteristics. Finally, the springs are used in the design of a proof-of-concept variable stiffness joint prototype. Experimental results on the variable stiffness joint confirm the viability of the proposed solution.
R. Carloni, V. I. Lapp, A. Cremonese, J. Belcari, A. Zucchelli (2018). A Variable Stiffness Joint With Electrospun P(VDF-TrFE-CTFE) Variable Stiffness Springs. IEEE ROBOTICS AND AUTOMATION LETTERS, 3(2), 973-978 [10.1109/LRA.2018.2793348].
A Variable Stiffness Joint With Electrospun P(VDF-TrFE-CTFE) Variable Stiffness Springs
J. Belcari;A. Zucchelli
2018
Abstract
This letter presents a novel rotational variable stiffness joint that relies on one motor and a set of variable stiffness springs. The variable stiffness springs are leaf springs with a layered design, i.e., an electro-active layer of electrospun aligned nanofibers of poly(vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene) [P(VDF-TrFE-CTFE)] surrounded by two electrodes of aluminum and held together by inactive material. To achieve a variable stiffness, different voltages and, therefore, different electric fields, are applied to the springs. The variable stiffness springs are electromechanically analyzed to highlight the voltage-deflection and force-deflection characteristics. Finally, the springs are used in the design of a proof-of-concept variable stiffness joint prototype. Experimental results on the variable stiffness joint confirm the viability of the proposed solution.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
