Algorithm Research And Related Designing Based On MEMS Folw Sensor

Meteorological elements such as temperature, humidity, air pressure, wind, light condition, rainfall,air quality index and so on are closed related to people's daily lives and they play very important roles in our country's industry, agriculture, meteorological monitoring, resource development, transportation and travel?facilities development and construction?environmental protection and many other fields. Wind speed and direction are a couple of important parameters in these meteorological elements and play key roles in meteorological monitoring. Traditional wind sensor usually consists of some mechanical structure, so it is bulky and expensive. The measurement accuracy of traditional wind sensor has been restricted because of human factors. MEMS wind sensor can be used for measuring wind speed and direction independently and it is more reliable and cheaper by using MEMS technology so it can replace the role of traditional wind sensor and become the main stream.Software system optimizing based on the MEMS hot wind sensor and hardware structure is researched in this article. The frame of software, function modules and algorithm of wind speed & direction are the focus of this article. Many function modules such as AD/DA module?UART module?I2C module?RTC module and external interruption module are developed and the whole frame of software and algorithm of wind speed & direction are designed Every function modules is separated out and its realization & designing thought is introduced, and solutions of problems which emerged in physical truth are listed in this article. Algorithm of wind speed and wind direction is the core of wind sensor system.This work consists of two parts:in the first, the principle of algorithm for wind measurement is introduced;the second, the algorithm which focuses on the variable selection, liner interpolation algorithm, mode switching, temperature compensation are desiged.The algorithm based on liner interpolation has a high accuracy,but its measuremental range is not very large(0?30m/s) beacuse of the defect of sensor and its workload is very huge(10 hour).The algorithm based on mode switching can guarantee the range of measurement(0?40m/s) and its accuracy is also high(0.5m/s±3%),but it has not considered the temperature effection in fact so that its could make error in extreme situation(-20? or 40?).The single axis temperature compensation algorithm can complete the temperature compensation and guarantee the high accuracy of wind sensor (0.5m/s±3%), large measurement range(0?40m/s) and good temperature characteristics. This work can guarantee the accuracy of wind measurement and decrease the workload of testing and it also considers the temperature characteristics.The wind sensor is measured in windturnnel,wind speed measurement range is from Om/s to 40m/s; temperature range is from -20 ? to 40?; wind speed&direction accuracy reaches 0.5m/s±3% in different temperature situation;sensitivity reaches O.lm/s.Test results show the key performance index of wind sensor reached the national standards so that the wind sensor can be laid a solid foundation for achieving the target of productization.