Dynamic force measurement for microassembly of surface MEMS structures

In-situ PVDF films bonded to the surface of flexible cantilever structure act as the effective micro-force sensors, they are mostly modelled using quasi-static relationship. However, such sensors are usually a significantly compliant and easily deformable structure in order to reach highly sensitive performance for micro force detection. As a result, this may be reasonable to consider bandwidth measurement and frequency response for achievement of high accuracy, and thus a dynamic modelling of such sensors become essentially necessary. In this paper, the 1-D and 2-D cantilever beam based micro-force sensors are designed and modelled on the basis of distributed parameter approach using Bernoulli-Euler equation. The resulting dynamic models can greatly enhance the measurement of micro force in microassembly. To verify the performance of the developed dynamic micro-force sensor, this dynamic sensor has been successfully used to guide a remote microassembly of the surface MEMS structures with microforce/visual feedback via Internet between USA and Hong Kong