Research On Key Technologies Of Werable Navigation System For Special Application

In recent years,wearable navigation and positioning devices have gradually become popular in the civilian market,and most civilian-grade portable pedestrian navigation devices use the positioning principle of GPS satellite positioning and wireless communication technology,in the open area of satellite positioning signals.Good positioning results can be obtained,but in special application environments where satellite navigation signals such as large supermarkets,shopping malls,tunnels,jungles and valleys are susceptible to interference or shielding,the navigation and positioning functions of this type of equipment will be seriously affected.Especially in some special industry fields,such as fire rescue,field search and rescue,underground exploration and other application scenarios,special operators carry GPS-based navigation and positioning equipment,when carrying out specific tasks,the navigation and positioning equipment carried is easy to be invalid or incorrectly positioned.It brings great difficulties to rescue missions and special operations.In serious cases,it will even endanger the personal safety of the users.In addition,special operators may have various complex motion modes such as lunges,jumps,and retreats when performing tasks.The navigation and positioning equipment carried must also adapt to the complex and variable human motion state.For this reason,in view of the harsh environment of the special operators and the complex motion modes,it is urgent to study the navigation technology in the low-cost and high-reliability special application environment to meet the navigation needs of special operators.To this end,the paper starts from the overall implementation of wearable pedestrian navigation,combined with the performance requirements of the special operation task for the navigation system,and studies the key technologies of the wearable navigation system for special applications.In view of the problem of navigation and positioning in the multi-motion mode during the movement of special workers,the human body model will be simplified into a 4-joint 5-link structure and kinematics modeling based on the Hanavan 15 rigid body model;on this basis The optimal configuration scheme of the wearable sensor was studied,and the position of the sensor's foot was determined.The characteristics of the inertial sensor output information under multi-motion mode such as running,jumping,retreating and lunge forward were studied.The multi-motion modal identification method for human body is applied to special applications,and the effectiveness of the method is verified.Aiming at the problem of cumulative error caused by the divergence of the strapdown inertia solution over time,the principle of detecting the zero-speed gait during human motion is studied,and the multi-condition comprehensive judgment method of zero speed of the foot is proposed.The measurement information is corrected for the pure strapdown solution.For the problem that the heading error is not effectively corrected during the motion process,an inertial error combined filter correction algorithm based on multi-motion modal identification is proposed.The estimation model of heading and position error is established,which effectively improves the heading accuracy during human motion and improves the positioning accuracy of the wearable navigation system.Aiming at the possibility that the special operators may have the opportunity to navigate information during the movement,the paper studies the Wi Fi positioning algorithm based on RSSI location fingerprint.The factors affecting the Wi Fi signal strength value and the influence of Wi Fi signal source layout on the positioning accuracy were studied by simulation and actual data acquisition.The fingerprint feature information in the location fingerprint database was studied.The KNN matching localization method based on fingerprint feature constraint was designed.Improve the matching accuracy;finally,through the actual data collection,the feasibility of improving the navigation accuracy and system performance for the effective opportunity information in the special application utilization environment is verified.In order to practically test the key technical content of the wearable navigation system for special applications,this paper builds a performance verification platform for wearable navigation system,designs the core module of the verification platform,and combines the key technologies of this paper.The performance of the wearable navigation system was verified.Experiments show that the proposed method does help to improve the positioning accuracy of the wearable navigation system.The research results of the thesis provide an important reference for the engineering realization of wearable navigation system for special applications,with strong theoretical significance and engineering practical value.