Method and device for measuring vector pressure taking advantage of capacitance change

Abstract

The invention provides a method for measuring vector pressure by using capacitance change and the device. In the invention pressure sensors of changeable capacitance are set under forced flat plate and each pressure sensors of changeable capacitance is connected with a circuit cell. By measuring capacitance change and frequency change of oscillation circuit changes of action point of bearing pressure of forced flat plate and pressure size are calculated. The method adopted by the invention is that capacitance values at different positions are obtained firstly; then by oscillation circuit electric signal with certain frequency range is obtained; and then vector difference between directions is calculated to obtain forced point corresponding to the forced flat plate and forced status information. The circuit cell mainly comprises oscillation circuit cell, amplifying and shaping circuit cell, frequency counting cell, vector calculating cell and outputting data cell. The invention is provided with simple structure. It can calculate pressure change and inspect the position of forced point quickly. It can emend it by itself. It is applied in multiple fields.

Description

field of invention [0001] The invention relates to a method and device for measuring and calculating the pressure on a plate by setting a group of variable capacitance pressure sensors under the plate and performing vector calculation through the measured capacitance change and the change of the electrical parameter of the measurement circuit, belonging to the field of electrical measurement . Background technique [0002] With the continuous improvement of the design and manufacturing level of consumer electronics products and user needs, it is necessary to measure, control and respond to various external physical quantities on more and more occasions, and pressure sensing is one of them. In many technical fields, various technical solutions are applied, such as pressure touch screen, resistive touch screen, infrared touch screen, capacitive touch screen and electromagnetic handwriting screen, which are used in computer input devices, electronic whiteboards and Mobile phon...

AI Technical Summary

Problems solved by technology

However, in this technical solution, the strain gauges can only be placed at four symmetrical positions with a certain distance from the top corner of the pressure-bearing panel, so that the pressure-bearing panel cannot be made into a transparent plate, otherwise the strain gauges and other elements will be seen. device, so it cannot be applied in fields such as touch screen

At the same time, this technical solution needs to install four supports under the four tops of the panel. The structure is complex, and the deformation of the pressure-bearing plate will also produce parallax. This technology also has certain limitations in the sensing of small pressures. Application is also inconvenient

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