Simulations of the snap‐through behavior of a fiber reinforced elastomer structure for the design of a simple clamping mechanism

Abstract

A glass fiber reinforced elastomer (FRE) sheet is used to design a simple clamping mechanism for prospective engineering applications. The mechanism is based on the phenomena of snap-through buckling of a segment of a shallow cylindrical shell. It is simply supported at the straight edges and actuated by edge moments. The main objective of such a mechanism is the resulting clamping force, being related to the response of the material under bending. Bending includes compressive stresses, and since the fibers are embedded in a very soft matrix, it is important to understand their contribution to the compressive stiffness of the FRE sheet. For this purpose, numerical simulations by means of the Finite Element Method are performed and a simulation strategy for predicting the clamping force of the mechanism is presented. The clamping forces predicted for FRE composites with and without the contribution of fibers to the compressive stiffness are compared to that of the pure elastomer. The results illustrate the potential of FRE based structures in mechanism-like applications. If an adequate clamping force is desired, the pure elastomer is not suitable for being used in this kind of clamping mechanism and the fiber reinforcement is necessary. If the fibers contribute to the compressive stiffness, a significantly higher clamping force is predicted. Furthermore, the FRE based structure shows a complex snap-through deformation pattern, which has to be taken into account in the design of the mechanism and which requires non-trivial simulation strategies.