Micro-mechanical two-dimension wind speed and wind direction sensor and signal processing circuit thereof

Abstract

The invention relates to a two-dimensional wind-speed wind-direction sensor and a signal processing circuit thereof, which relates to a two-dimensional wind-speed wind-direction sensor which is based on a micro-mechanical (MEMS) lift-off process and a constant temperature control and heat temperature difference detection circuit. A chip temperature measurement resistance Rs in the center of the sensor and a reference resistance are connected to be a Wheatstone bridge form, which are amplified in difference, and finally, a voltage / current transition element are utilized to drive a heating resistance Rh, and the constant temperature control of the sensor is achieved through utilizing optical and thermal negative feedback. Eight temperature-measuring resistances which are symmetrically arranged and the resistance values are same are divided into two groups to form a Wheatstone whole bridge circuit to measure wind speed in X and Y direction. The output of the Wheatstone bridge is conversed into digital quantity to enter MCU through a multiple selector Mux and an A / D convertor after being magnified, and the wind speed and the wind direction values can be got through calculation, and finally, LCD display and digital output can be achieved. The invention has the advantages of simple and reliable technique, high sensitivity, low power consumption, fast response time and the like.

Description

technical field [0001] The invention relates to a two-dimensional hot film wind speed and wind direction sensor based on micro-mechanical (MEMS) stripping technology, and a constant temperature difference control and measurement circuit. Background technique [0002] Wind speed and wind direction are very important components in meteorological measurement. As we all know, although wind cups and wind vanes that use machining can also measure wind speed and wind direction, these mechanical devices are easy to wear due to moving parts, and at the same time have the disadvantages of large volume, high price, and need for frequent maintenance. The micro-flow sensor based on MEMS processing technology has the characteristics of small size, low price and good product consistency, and it has become a hot spot in the research of fluid sensors in recent years. Van Putten proposed the first hot wire flow sensor based on silicon micromachining technology in 1974. In order to simultane...

AI Technical Summary

Problems solved by technology

As we all know, although wind cups and wind vanes that use machining can also measure wind speed and wind direction, these mechanical devices are easy to wear due to moving parts, and at the same time have the disadvantages of large volume, high price, and frequent maintenance.

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