Displacement measurement method based on piezoelectric ceramic open-loop modulation

Abstract

The invention provides a displacement measurement method based on piezoelectric ceramic open-loop modulation, belonging to the technical field of measurement. The displacement measurement method provided by the invention is characterized by comprising the following steps of: applying a periodic triangular wave driving voltage to piezoelectric ceramic to enable the piezoelectric ceramic to reciprocate; respectively finding out reference positions corresponding to a certain length of the piezoelectric ceramic in opposite movement directions and obtaining driving voltages corresponding to the reference positions; and calculating an average value of the driving voltages; and calculating a displacement amount to be detected by multiplying the change of the average value by gradients of middle section areas, which are close to be linear, in an average value curve of a displacement-driving voltage curve in the process of raising the driving voltages and a displacement-driving voltage curve in the process of decreasing the driving voltages under the driving of the periodic triangular wave driving voltage. The method provided by the invention has the advantages of effectively improving the hysteresis and the non-linearity of the piezoelectric ceramic and improving the precision of the displacement measurement; the displacement measurement can be realized by only carrying out open-loop control on the piezoelectric ceramic, so that the system complexity and the cost are not increased, the method is convenient to combine with other displacement measurement methods and the large-scale high-precision displacement measurement can be realized.

Description

technical field [0001] The invention relates to a displacement measurement method based on piezoelectric ceramic open-loop modulation, which belongs to the field of measurement technology. Background technique [0002] Piezoelectric ceramics is a functional ceramic material that can convert mechanical energy and electrical energy to each other. Under the action of mechanical force, it deforms, causing the relative displacement of charged particles, so that positive and negative bound charges appear on the surface of the material. This phenomenon is called piezoelectricity. effect; on the contrary, when a voltage is applied to the piezoelectric material, the material will produce geometric deformation, this phenomenon is called the inverse piezoelectric effect. Due to the development of power supply technology, the inverse piezoelectric effect has been widely used and plays an important role in the fields of electronic technology, optics, ultrasound, precision machinery, and ...

AI Technical Summary

Problems solved by technology

Although the closed-loop control effectively improves the hysteresis and nonlinearity, it brings new problems such as the decline of dynamic characteristics, the complexity of the system, and the increase in cost.

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