Method Of Zero Velocity Update For Indoor Pedestrian Navigation Based On Pressure Assistance

There are still many problems in indoor positioning technology,such as the complex indoor environment,the diversity of application requirements and the difficulty in seamless positioning.Although infrared,WLAN,Ultra Wide Band(UWB)and ultrasonic technologies are well developed,beacon nodes need to be preinstalled in the building.In the face of complex indoor environment,the design can be assisted autonomous navigation and easy portable Micro Inertial sensors(Micro Inertial Measurement Unit,MIMU)has become a mainstream direction,this article will design based on the pressure of auxiliary indoor pedestrian navigation zero velocity correction method,the method is using pressure auxiliary Micro Inertial sensors zero velocity interval,and design zero velocity correction algorithm based on extended kalman filter to realize autonomous navigation.The research work of this paper mainly includes the following aspects:First,the basic theoretical knowledge of pedestrian navigation,including the transformation between coordinate systems,strapdown inertial navigation basic theory,kalman filter theory,pedestrian gait description and characteristics;The initial alignment is made by using the navigation Angle assisted by the magnetometer to eliminate the gyro alignment error.Secondly,in order to realize the accurate zero-speed interval detection conditions,the zero-speed interval detection based on micro-inertial sensor and the zero-speed interval detection based on pressure sensor are studied,and the detection conditions are comprehensively analyzed and compared,and the zero-speed correction algorithm of extended kalman filter is designed according to the detected zero-speed interval.Finally,in order to verify the effectiveness and accuracy of the algorithm.By comparing the zero-speed correction method based on pressure assistance with the zero-speed correction method based on inertial sensor,the difference in indoor positioning and navigation accuracy was analyzed in the presence of or without pressure sensor assistance.In this paper,two sets of experiments were set up for verification.The results show that the positioning accuracy of the zero-speed correction method is about 3%,which basically meets the requirements of indoor positioning.