Symmetric air-spaced cantilevers for strain sensing

Large mechanical strain is desirable for many devices such as cantilever-based accelerometers and vibration energy harvesting devices. Air-spaced cantilevers are proposed to significantly increase the mechanical strain experienced by the cantilever beams. In this paper, an analytical model for the bending of symmetric air-spaced cantilevers is established by decomposing the cantilever deformation into pure bending and S-shape bending. This model was further verified by a discrete component model. A criterion to determine the dominant bending mode is presented. Finite element simulations and experiments were also conducted and showed a good agreement with the analytical model.