The Development And Design Of Measurement Circuit For The Multi-Axis Piezoelectricity Force Sensor

With the development of sensor technologies, piezoelectric multi-axis force sensor, which transfers the information of force and torque into electric signal, obtained more and more attention. Especially with the development of robot technology, to realize intelligent and human-like robot, piezoelectric multi-axis force sensor applications has become increasingly widespread. However, the output of piezoelectric multi-axis force sensor is very weak; usually there is a secondary instrument to amplify its output signal. At present, the secondary instrument of piezoelectric multi-axis force sensor is widely used with charge amplifier, which the most significant feature is the sensitivity of the charge amplifier has nothing to do with the length of sensor cable.In this paper, the two different equivalent model and its equivalent circuit model of piezoelectric force sensor are discussed in detail; We focused on the design of the Q/V transform level, amplifier level, filtering level, output level and the overload level of quasi-static charge amplifier, completed the simulation and the actual production of the charge amplifier, and the relevant tests of charge amplifier were done under the current experimental conditions.In this paper, the main work completed includes:①Know of the development situation of multi-axis force sensor and measuring circuit research at home and abroad.②From the piezoelectric effect, discussed two different equivalent model and the corresponding equivalent circuit of piezoelectric force sensor.③Completed the charge amplifier design and simulation in Multisim software.④Designed the software program of data acquisition system in the LabVIEW software environment by used of NI data acquisition cards.⑤Carried out the development of the quasi-static charge amplifier and relevant laboratory tests under the current experimental conditions.