Aiming at the problem that the positioning accuracy of common integrated navigation systems will decline rapidly in areas with weak satellite signals such as tunnels

canyons

forests

etc.

a Beidou/strapdown inertial navigation (SINS)/odometer (OD) integrated navigation and positioning terminal is designed.The terminal design takes OMAP-L137 processor as the core

including Beidou

SINS

odometer

4G communication and power supply modules.The data processing part takes the difference between the Beidou navigation receiver and the pseudo range and pseudo range rate calculated according to SINS/OD as the measured value

and uses the extended Kalman filter (EKF) algorithm for data fusion and error estimation.The experiment results show that the maximum position error of Beidou/SINS/OD integrated navigation and positioning terminal is 46.82 m and the error drift is 0.94% when the total mileage is 5 km when the satellite is unlocked

which can effectively improve the problem of positioning accuracy decline caused by the obscuration of satellite signals

smooth the vehicle trajectory and improve the navigation and positioning accuracy.