传感器采样延时是多传感器信息融合过程中面临的一个重要问题，全球定位系统/惯性导航系统(GPS/INS)的组合导航系统是智能汽车常用定位方式，但常面对GPS采样延时的问题， 因而会造成对INS误差状态的错误估计，影响定位定速的精度.本文针对该问题，在传统的GPS/INS松耦合组合导航模型的基础上提出一种延时估计和补偿的算法.首先建立延时估计模型，估计时间同步误差，然后构建残差传播方程，利用残差重构的方式进行延时补偿，实现基于软件的时间同步.根据试验中对速度、位置误差及均方根误差的分析，改进的滤波算法有效地降低了GPS采样延时引入的误差，提高了定位和定速的精度.
Time-delay is an important issue in multi sensor data fusion. As a common positioning method of an intelligent vehicle, global positioning system/inertial navigation system (GPS/INS) always suffers from an internal time-delay which can cause an error estimation of the INS error state. Based on the traditional loosely coupled integrated navigation system, this paper proposed an algorithm for delay estimation and compensation. Firstly, the delay estimation model was formulated to estimate the time synchronization error. Then, the residual propagation equation was constructed, and the delay compensation was carried out by means of residual reconstruction. The time synchronization was implemented in a software-based scheme. According to the analysis of errors and root mean square errors of velocity and position in the experiment, the improved filtering algorithm was able to effectively reduce the error caused by GPS sampling delay and improve positioning and velocity measurement accuracy.
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