The design and development of a mirco-force sensing device

An advancing micro-force sensing device that can measure force in the range of sub-micro-Newton (muN) is designed and realized in this paper. To accurately measure the micro interactive force (For example, adhesion, surface tension, friction, and assembly force) between the tool and the object during micromanipulation, the polyvinylidene fluoride (PVDF) is used to fabricate a highly sensitive force sensing device. In this paper, the relationship model of the interactive force and the charge generated on the PVDF surface, the design of the signal processing method of PVDF output are illustrated. The transformation model between the micro interactive force and the signal of the sensing device is built. A new calibration method of the sensing device is presented. Experiment results verify the accuracy of the sensing device´s transformation model, the effectiveness of the signal processing method. The results also show the sub-muN sensitivity of the sensing device. The micro-force sensing technology developed in this paper will promote the efficiency, and decrease the cost of micromanipulation and microassembly.