Absolute type capacitor angle displacement measurement sensor

Abstract

The present invention relates to an absolute type capacitor angle displacement measurement sensor. The sensor comprises a sensitive structure, a signal modem circuit and an error compensation and fusion module; the sensitive structure comprises a first stator, a rotor and a second stator which are vertically arranged in parallel; the outer side of the top of the first stator is provided with an accurate measurement collection electrode, and the inner side of the top of the first stator is provided with an accurate measurement exciting electrode; the outer side of the bottom of the rotor is provided with an accurate measurement sensitive electrode, the inner side of the bottom of the rotor is provided with an accurate measurement coupling electrode, the outer side of the top of the rotor is provided with a rough measurement sensitive electrode, the inner side of the top of the rotor is provided with a rough measurement coupling electrode, and the accurate measurement and rough measurement sensitive electrodes and the accurate measurement and rough measurement coupling electrodes are equipotential bodies; the outer side of the bottom of the second stator is provided with a rough measurement collection electrode, and the inner side of the bottom of the second stator is provided with a rough measurement exciting electrode; the signal modem circuit is configured to measure the accurate measurement angle displacement and the rough measurement angle displacement; and the error compensation and fusion module is configured to perform error compensation to calculate the absolute angle displacement. The absolute type capacitor angle displacement measurement sensor is widely applied to angle displacement measurement sensors.

Description

technical field [0001] The invention relates to an angular displacement sensor, in particular to an absolute capacitive angular displacement measurement sensor, belonging to the field of angular displacement sensors. Background technique [0002] Angular displacement sensor is a displacement sensor that converts physical quantities such as rotational angular position and angular displacement into electrical signals. It is a sensor used to detect angle, speed, length, displacement and acceleration in the field of automation. Its application is as large as CNC machine tools and robots. , packaging machinery, printing machinery, elevators, factory automation-related equipment position detection and transmission speed control, as small as the rotation measurement and control of office automation equipment such as disks and printers, has become an indispensable part of various fields. [0003] At present, there are many kinds of rotation angle displacement sensors on the market. ...

AI Technical Summary

Problems solved by technology

[0003] At present, there are many kinds of rotation angle displacement sensors on the market. According to the detection principle, they can be divided into optical encoders and magnetic encoders. Among them, optical rotary encoders are widely used, followed by magnetic encoders. The existing angular displacement measurement The sensor has high precision, but has disadvantages such as relatively large volume, complex processing, high cost, harsh environmental requirements, and poor dynamic characteristics. For example, magnetic encoders are complex in processing, high in cost, heavy in weight, and sensitive to electromagnetic environments. The lower capacitive angular displacement sensor has high stability, can be used for non-contact measurement, has good dynamic response, and adapts to harsh environments. It has been considered by more and more people to be the most promising sensor.

[0004] At home and abroad, there are many studies on capacitive sensors used to measure angular displacement, and great breakthroughs have been made, mainly focusing on the improvement of sensitive structures. The conventional sensitive structure is a fan-shaped split-lobe type, and the ability to obtain angular displacement information is limited. Sensitivity is also limited by processing accuracy, and the demodulation circuit is complex, so absolute angular position measurement cannot be achieved. Most capacitive angular displacement sensors can only be used for relative measurement, and the dynamic range is limited

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