Vehicle-mounted strapdown/satellite tight-combination seamless navigation method

Abstract

The invention discloses a vehicle-mounted strapdown / satellite tight-combination seamless navigation method. The method comprises the following steps that a system is initialized; messages are output by a GPS, inertial measurement unit data are output by a SINS, and synchronization is carried out; the GPS messages are analyzed to obtain rough pseudorange, Doppler shift and satellite position parameters, and compensation for the parameters is carried out to obtain fine pseudorange, pseudorange rate and satellite position parameters; navigation calculation is carried out on the inertial measurement unit data to obtain vehicle state, speed and position parameters; if the number of visible satellites is larger than or equal to 4 is judged, if the number is larger than or equal to 4, 4 satellites are selected to carry out tight combination filter calculation, and is the number is smaller than 4, an intelligent combination algorithm is used; vehicle navigation parameters are output, and if navigation needs to be continued, the step 2 is redone. Tight combination navigation and the intelligent combination algorithm are used for realizing seamless switching of different visible satellites, and vehicle seamless navigation is reliably guaranteed.

Description

technical field [0001] The invention relates to a navigation method, in particular to a vehicle strapdown / satellite tight combination seamless navigation method. Background technique [0002] In order to obtain the real-time position and attitude information of the mobile carrier, various navigation methods have been proposed and adopted. Among these navigation methods, Strap down Inertial Navigation System (SINS for short) and Global Positioning System (GPS for short) are the most widely used. There are many combinations of SINS and GPS systems, mainly including loose combination, tight combination and deep combination. The loose combination method directly uses the speed and position information output by the GPS receiver to combine with SINS. The deep combination method utilizes SINS information to assist GPS to track and capture satellites. The tight combination method utilizes the combination of the original GPS information and the SINS, and because it avoids the sec...

AI Technical Summary

Problems solved by technology

There are two reasons for this. The first is that the SINS / GPS tight combination technology involves the technical details inside the GPS receiver, which requires multiple conditions such as pseudorange, pseudorange rate, original observation output of satellite ephemeris, and stable clock characteristics. , but at present, off-the-shelf GPS receiver modules are basically used in China, and the secondary development is difficult; the second is that the computational complexity of the compact combination technology is relatively large, and the computing power of the hardware platform of the domestic navigation system is difficult to meet the demand. Accurate software algorithm, or improve the computing power of the hardware platform

This restricts the in-depth study of tight combination to a certain extent, so at present, SINS / GPS integrated navigation mostly adopts loose combination, and the research on tight combination develops slowly.

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