冗余捷联惯组故障重构策略研究

Research on Reconfiguration Strategy and Structure for Redundant IMU

针对因漏警率和参数不确定性所引起的多传感器融合精度损失进行数学建模并开展研究。首先对高低精度两传感器融合模型给出分析,进而对三正交一斜置配置给出斜表是否参与融合的精度影响分析。分析表明在考虑漏警率等因素的前提下,所有惯性表均参与估计有精度损失风险。基于所构建的模型给出冗余捷联惯组的重构策略,在策略的指导下提出双三正交架构,并与正十二面体配置进行对比。对比结果表明双三正交在无故障和一度故障下性能和正十二面体配置相当,考虑不确定性,双三正交架构有一定优势。

The accuracy of multi-sensor fusion considering with fail alarm and uncertainty is analyzed. Firstly, the fusion of two sensors with different precision are investigated. Then, the impact is analyzed whether the fusion includes skew axe for the configuration of three orthogonal axes and one skew axe. It is shown that the presence of fail alarm and the fusion accuracy would not improve but get worse, including all sensors＇ uncertainty. A more appropriate reconfiguration strategy based on the built model is presented. A structure of dual triads is proposed under the guidance of strategy and compared with the configuration of dodecahedron. It is proved that the optimal performance of two structures is almost equal in the absence of failure and one sensor failure. A structure of dual triads has its advantages considering uncertainty and computation complexity.