Research On Indoor Location Method Based On UWB/INS Combination

With the rapid development of global satellite navigation and positioning technology,outdoor navigation systems are booming.The navigation system composed of global navigation satellite system(GNSS)and inertial navigation system(INS)performs high positioning accuracy.But in the indoor environment,the traditional GPS signal can not penetrate the building,so it is difficult to obtain accurate satellite navigation information,of course,hard to locate.With the increasing demand for high-precision indoor positioning,various indoor navigation technologies have developed rapidly,such as WIFI,Bluetooth and RFID technology,but a single positioning system is difficult to meet the actual application requirements.In this context,a joint positioning method based on Ultra Wideband(UWB)ranging and inertial navigation system is proposed,and make a detailed study of it.In this paper,pedestrians are taken as the research object,focusing on the navigation and positioning methods for pedestrians in indoor environment.In order to improve the UWB positioning accuracy,a Kalman filter-based location tracking model is seted.Further more,aiming at the advantages and shortcomings of the UWB and inertial navigation system,a joint positioning method based on UWB and inertial navigation system is proposed by using multi-sensor fusion technology,and its performance is verified by simulation.Furthermore,in order to improve the navigation accuracy,reduce the system cost and the cumulative error of inertial navigation system to meet the navigation and positioning needs of pedestrians in complex indoor environment,the pedestrian dead reckoning(PDR)system is studied,judging the standing state of pedestrians by the output of gyroscope and accelerometer.Zero velocity update(ZUPT)is implemented at the stand time to provide the system's velocity error observation,and UWB system is used to provide the position error observation.To summarize,the ZUPT-UWB/INS integrated positioning method is proposed.Finally,the results of walking experiments show that the average positioning error of UWB/INS is 0.21 m,while the error of ZUPT-based UWB/INS is 0.17 m.Compared with single UWB navigation positioning method,the positioning error is reduced by 32.3% and45.2% respectively.