The Research Of The Vehicular Strapdown Gyrocompass Alignment Technique

Inertial navigation technology has been widely used in the aerospace,aviation and navigation and other aspects.With its unique independence,stability has been strongly welcomed the military field.So,inertial navigation technology has been a focus of research in recent years.And the initial alignment technology is an important part of inertial navigation.The SINS initial alignment system technology is a hot issue in recent years.Many researchers have made in-depth study on this.This article is based on the special circumstances set out in the car's own unique characteristics to research in-vehicle systems SINS inertial compass alignment,the main contents are as follows:1.For the special case of large azimuth misalignment angle,thi paper studied based on the parameters of the incident SINS compass alignment method,depicts strapdown compass azimuth alignment process in large misalignment angles environment,analyze the large azimuth misalignment angle case SINS compass aligned schematics,elaborated the various system parameters variation,and made a detailed comparison with the small misalignment angle environment.By the final,characteristics of the natural oscillation frequency con depending on the current stage in the alignment choose different value to complete the alignment process different stages.Through theoretical analysis and simulation shows that chose to ramp function with respect to time to carry out time-varying settings,better aligned completed compass case of large misalignment angles,compared to conventional compass alignment method,time-varying compass whether aligning the speed and accuracy of alignment have a clearly advantage.2.In order to meet the requirements of rapid operational response vehicles,we study the carrier vehicle for moving base compass alignment problems.Because the vehicle odometer to set a separate installation of equipment on board,so it was independent,free from the interference of exogenous factors,and the data sources can provide problems for a long time,so in this paper,the odometer information assisted in moving base case to complete the compass loop alignment.Through horizontal alignment,orientation rough estimate and orientation precision alignment completed a three-step alignment base on moving base.Finally we achieve the desired alignment results.3.The car navigation system has the distinctive characteristics because of the vehicle itself.In this paper,from the characteristics of the vehicle unique,study the lever arm effect carrying vehicle,through specific graphic presentation,deduced the effect of carrying out the lever arm effect under the odometer velocity error formulas,the error compensation method of lever arm effect.And research the influence of out arm in compass alignment.Finally,the error formula was deduced,and we offer the compensation method.4.Analyzed and discussed the structure and specific formation process of cone error.Analysis the cone error in strapdown compass and proposed by SINS coning compensation algorithm to solve such problems.Several forms of compensation for cone optimization algorithm are compared and choose the appropriate algorithm.