Research On Personnel Positioning Technology Based On Multi-source Information Assisted IMU

With the development of micro electro mechanical systems(MEMS)technology,the inertial measurement units(IMU)composed of MEMS gyroscopes and accelerometers have many advantages,such as small volume,high precision,low power consumption,wide application prospect,etc.,and become a research hotspot in the field of personnel positioning technology.However,in the inertial personnel positioning system,its positioning accuracy and durability still can not meet the practical needs.In this thesis,a multi-source information aided IMU technology is studied,which includes gyroscope,accelerometer,barometer,manometer,magnetometer,temperature sensor and other core devices,as well as zero velocity update,pedestrian dead reckoning,and other models and algorithms can not only effectively make up for the lack of autonomy and concealment,but also improve the positioning accuracy and duration of personnel.The main research work of this thesis is as follows:Firstly,the accelerometers and gyroscopes in IMU are calibrated and temperature compensated.The accelerometer is calibrated in static and dynamic motion modes,and the foot accelerometer is dynamically compensated by multi-source zero speed update technology.The static installation error of gyroscope is calibrated,and the temperature lag model is established to compensate the temperature error.The temperature lag model of moving average algorithm is used to compensate the temperature error of gyroscope in IMU device.Then,the multi-sensor parts of the waist and foot are used to calculate the pedestrian gait heading.A multi threshold algorithm based on peak,zero crossing and trough waist of MEMS accelerometer and foot pressure is used to detect pedestrian steps.The step length of pedestrian is calculated by the integration method of waist acceleration and foot acceleration.The combination of magnetometer and accelerometer is used to assist gyroscope to calculate heading angle.Finally,according to the multi-source information assisted IMU technology to achieve an independent positioning target,multi-source positioning algorithm is used to fuse and update the multi-sensor data,and update the pedestrian's step number,step length,heading and altitude attitude data.Through simulation prediction and pedestrian walking experiment,horizontal relative position error is less than 0.3%,the effective working time is more than 30.00 min,which achieves the expected effect of the technical scheme.