Geomagnetic Data Acquisition System Of The Encoder Combined With The Inertial Navigation

We propose the "Digital City,Smart City" to promote the continuous improvement of the cause of mapping.The use of current communication technology and location information services(Location Based Services,LBS)and other key technologies can make people's livelihood,urban services,industrial and commercial activities,including a variety of needs do intelligent response.Global Positioning Systems(GPS)location information services,widely used in car navigation and portable navigation,where people can quickly obtain accurate location information through location information services.However,in the large shopping malls,large shopping centers,airports,parking and other indoor environment is unable to obtain accurate location information.Therefore,many scholars gradually shift the focus of research to the indoor location information services.As the indoor environment is more complex than the outdoor,so the requirements of the indoor positioning technology is higher.At present,a new type of indoor positioning navigation "geomagnetic indoor positioning",sought after by many scholars,the key step is the construction of pre-geomagnetic reference map.For example,when we build a geomagnetic datum for very large shopping centers and shopping malls,because of the changing position of the items,We need real-time updates of geomagnetic datum maps.In the huge space to build geomagnetic datum map,improve the efficiency of the baseline map collection is essential.In this paper,the following work is done to improve the efficiency of benchmarking:1)We have developed a set of geomagnetic data acquisition system for the collection of geomagnetic datum maps in the indoor environment.The system integrates a variety of sensors(inertial sensors,encoders,geomagnetic sensors),and fusion a variety of sensor data in the geomagnetic data acquisition system,we use the Programmable Logic Controller(PLC)program to control the pedestrian trajectory of the acquisition system artificially,and the PC receiver real-time monitors and stores the data collected by the acquisition system platform.2)Two channel encoders collect data information and achieve synchronous output,In the monitoring,display,storage,we have developed a preprocessing for encoding the signal application to achieve based on the Labview program development environment.3)We use the Kalman filter algorithm to smooth,optimize the LPMS-CURS inertial navigation sensor to collect the attitude angle information level,to achieve the desired results.4)The sampling frequency between the different sensors are set to 100 Hz,and then we use the PC side to provide the synchronization clock signal to achieve the pulse signal data information,attitude angle data synchronization acquisition.Finally,the data into the library,and solve the location coordinates information.5)Aiming at the characteristics of indoor complex environment,a variety of motion trajectories are simulated,and different trajectory algorithms are used to simulate the output of each trajectory in Matlab-based environment.6)In order to determine the accuracy of the simulated motion,an experimental check field was established to test the trajectory of the mobile platform in the process of motion,and the expected effect was achieved.7)We use the Kriging interpolation method(Kriging)to construct high-precision geomagnetic datum maps for position coordinate information and geomagnetic data.Through continuous experiment,optimization,improvement,Geomagnetic data acquisition system platform has been successfully applied to the indoor environment,the system is stable,the sampling interval can reach 100 Hz or less,the speed control is very strong,synchronous acquisition serial port docking to achieve "0" error,the track coordinates relative error is better than 1cm.