Research On Extraction Technology Of Road Surface Slope Based On MEMS Sensor

The measurement of road slope is of great significance to the development of fine navigation system and scene operation simulation system.Acceleration estimation based on micro-electro-mechanical system(MEMS)sensors usually requires additional sensors to extract the slope of road,and it is also troubled by cumulative errors.The proposed method for extracting the slope of the road surface based on the smart phone MEMS sensor does not require additional sensor support.The zero acceleration state detection method is used to correct the cumulative error,and then realizes the position calculation and slope extraction through the rotation quaternion estimation and a new slope extraction method.Firstly,the working principle of the MEMS sensor in the smart phone for data acquisition is introduced,including the working principle of three-axis accelerometer,three-axis gyroscope and three-axis magnetometer,and the common coordinate system and the conversion relationship between coordinate systems are explained.Secondly,a method of zero acceleration state detection is proposed,which realizes the cumulative error processing without additional sensors.Based on the two different output results of the zero acceleration state detection,the method of performing the rotation quaternion initialization in the zero acceleration state is proposed,the rotation quaternion is estimated.According to the obtained rotation quaternion and the data collected by the sensor,coordinate transformation and gravity acceleration compensation can be performed on the acceleration,and the obtained motion acceleration is integrated to realize the solution of the platform position.The method of using the invariance of gravity acceleration direction and the change of gravity acceleration vector direction in the carrier coordinate system is proposed to realize the slope information extraction.Finally,using the smart phone to build three experimental platforms for data collection,through the IP interconnection method,the collected data is synchronized from the mobile MATLAB of the mobile phone to the MATLAB of the computer,thereby threshold setting,zero acceleration state detection and rotating quaternary estimation,the data processing is realized.The correctness and effectiveness of the proposed position solution and slope extraction algorithm are verified by analyzing the results of three experimental schemes.