Research On Multiple Gait And 3D Indoor Positioning System

There are more and more needs for high-precision positioning in domestic and foreign markets,and the mostly popular method is the global positioning system,but the GPS can't work in indoor or extreme environments.So Strap-Down Inertial Navigation System came into being,it can solve the pedestrian position real-time through inertial navigation only requires pedestrians to wear inertial sensors.The main scene of indoor positioning contains pedestrians moving between different floors,and moving with different gait,such as walking and running,in view of these scenarios,this paper designed a foot-mounted inertial navigation system,the system can achieve 3D positioning in a variety of gait.Most indoor positioning schemes based on strap-down inertial navigation can only be used for normal walking,and once the pedestrian is walking fast or running,the system will be completely fail.As a result of walking,the foot will have a contact with the ground in every step,when foots are affected by the impact from the ground,which results in a large amount of change in the sensor for a short period of time,and the usual sensor cannot identify the change,then the acceleration data will be distorted,so height positioning is a tricky problem.So,most researchers only focus on the positioning of two-dimensional plane,regardless of the calculation of the height.This paper presents a positioning system suitable for multi-gait.By analyzing the inertial data of different modes of motion,a heuristic zero-speed detection algorithm is designed,which can accurately detect the zero-velocity time of pedestrians in a variety of gait scenes,and then the speed and the displacement are updated in the Kalman Filter.And the barometer is fused with accelerometer for the calculation of height.The experimental results show that the average distance error is 2.59%,the average distance error is 5.85%during running and the average height error is about 0.275m when the pedestrian is going stairs.This paper adds two points design to the traditional inertial navigation enhance the robustness of the system effectively,the new system increase of the system application scenarios,such as anti-terrorism operations,disaster relief,shopping malls and so on.