Development of Force Monitoring Transducers Using Novel Micro-Electromechanical Sensor (MEMS)

MEMS piezoresistive sensors are a favourable and attractive option for strain detection due to a number of key advantages such as high sensitivity, low noise, good scaling characteristics, low cost and their ability to have the detection electronics circuit farther away from the sensor or on the same sensing board. This paper represents the results obtained at characterization of novel transducers to be employed into force monitoring systems. Each transducer comprises a coherently designed novel mechanical transducer and a positional MEMS sensor with very high accuracy. The exploited positional MEMS microsensor and the mechanical transducer are presented in this paper. The particular MEMS sensor provides a voltage output signal having sensitivity in the range of 240 µV/µm at 1V DC voltage supply. The range of operation of the mechanical transducer is optimized to fit the 500 µm travel range of the microsensor. A finite element model is constructed to simulate the system structure using the commercial FE package. Two prototypes of force transducers are described and manner of used silicon MEMS sensor attachment is demonstrated. An experimental set-up and experimentally measured load curve are presented in the paper. Diagrams force/voltage for two prototypes at different supply voltage 1V and 2V are revealed