一种新的惯性/视觉组合系统初始对准的时域约束方法

A novel time-domain constrained approach for the initial alignment of INS/vision integrated system

视觉导航作为一种新兴的导航方式,近年来受到越来越多的关注。在惯性/视觉组合导航系统中,惯性子系统和视觉子系统之间的相对位姿参数估计是一个必须解决的重要问题。为此,基于增广时域约束建模,提出了一种组合系统内参标定的方法。该方法首先在惯性/视觉组合系统的传统标定模型的基础上,对系统状态和观测量的时域相关性进行了分析,建立了其时域约束模型;然后,采用可观测性分析方法,对该时域相关的多维非线性模型进行了可观测性分析,证明了时域约束条件的引入,能够改善系统的可观测性。最后对惯性/视觉组合导航系统分别进行了静态和动态实验,结果对比验证了时域约束模型的有效性。

Visual navigation as a novel navigation manner has attracted more and more attentions in recent years.In low cost INS/vision integrated navigation system,the relative position and gesture parameter estimation between INS subsystem and vision subsystem is an important problem to be solved.In order to solve the initial estimation problems involved in INS/Vision integrated system,this paper proposes a novel internal parameter alignment approach for integrated system based on augmented time-domain constraint modeling.At first,on the basis of traditional initial alignment model of INS/Vision integrated system,the time domain correlation of system state and measurement data is analyzed,the time-domain constrained model is established.In order to verify the advantage of state-evaluability,both the traditional alignment model and the corresponding time-domain constrained model are analyzed with nonlinear observability analysis method.It is proved that introducing time domain constraint can improve the observability of the system.Finally,two groups of static and dynamic numerical simulations and experiment tests were carried out,and the corresponding results verify the effectiveness of the proposed time-domain constrained model.