一种捷联惯导阻尼超调误差抑制算法研究

Research for SINS Damping Overshoot Error Suppression Algorithm

针对捷联惯导系统在阻尼状态切换时产生超调的问题,提出一种基于"双模"解算的捷联惯导阻尼超调误差抑制算法。基于捷联惯导的力学编排,建立了系统水平回路的控制模型,分析了系统阻尼和无阻尼状态切换时超调误差产生机理。在此基础上,设计了系统阻尼和无阻尼并行的导航解算算法,在切换状态超调期内利用无阻尼导航输出校正阻尼导航输出,抑制状态切换超调误差。算法将捷联惯导系统IMU的输出同时接入两个解算回路。两个回路同时、独立进行导航参数的解算。系统工作在无阻尼状态时,惯导系统输出无阻尼回路的导航参数。在状态切换的超调期内,惯导系统仍输出无阻尼回路的导航参数。状态切换的超调期结束后,惯导系统输出阻尼回路的导航参数。仿真结果表明,该算法能够抑制惯导系统阻尼状态切换时产生的超调误差。同时,该算法使校正回路设计简洁,工作稳定可靠。

A double-model based SINS damping overshoot error suppression algorithm is proposed to solve the problem that there will be an overshoot when SINS＇s working condition is switched. Based on the SINS mechanical layout, the aclinic loop control model is estab- lished. The mechanism why there will be an overshoot when SINS＇s working condition is switched between damping and no damping is ana- lysed. On this basis, the damping and no damping navigation decoding algorithm is designed using no damping navigation output to correct damping navigation output during the overshoot period. In this way, the overshoot error is restrained. The output of SINS IMU is accessed to the two solution loops. Two loops calculate the navigation parameters independently at the same time. INS outputs the navigation parame- ters of the no damping network when the system working in no damping state. And INS still outputs the navigation parameters of the no damping loop during the overshoot period. Then, after the overshoot period, INS outputs the navigation parameters of the damping network. The simulation results show that this algorithm can inhibit SINS＇s overshoot error when the damping state switches. At the same time, this algorithm makes the design of correction circuit simple and the system reliable.