基于SINS/OD/高度计的车载重力异常测量方法

Vehicle gravity anomaly measurement methods based on SINS/OD/altimeter

车载重力测量沿地球表面实施,其较慢的速度和机动灵活的特点为高精度地面重力测量提供有利条件。传统动基座重力测量严重依赖全球定位系统(GPS)而无法实现完全自主性,基于捷联惯导(SINS)/里程计(OD)/高度计组合导航提出一种新的自主无源车载重力异常测量方法。组合导航系统提供了高精度的比力、姿态和载体加速度信息,气压高度计用于抑制高度通道的发散,通过直接差分法即可实现重力信息的获取;对比了以航位推算位置(SINS/DR)、里程计速度(SINS/OD)、位置速度(SINS/DR/OD)为量测和传统SINS/GPS这4种方法的测量精度,分析量测选择对所提方法测量效果的影响。重复测线仿真及单测线跑车试验结果表明:所提方法可以实现完全自主的车载重力异常测量,相比传统SINS/GPS方法具有普遍的精度优势,SINS/OD与SINS/DR/OD测量精度相差不大,且优于SINS/DR测量方法。

Vehicle gravimetry is carried out along the surface of the earth.Its slow speed and flexible maneuverability can provide favorable conditions for high-precision ground gravimetry.Due to its heavy dependence on the global positioning system(GPS),traditional gravimetry on a moving pedestal cannot achieve complete autonomy.A new autonomous passive method based on strapdown inertial navigation system(SINS)/odometer(OD)/altimeter integrated navigation was proposed to measure vehicle gravity anomaly.The integrated navigation system provided high-precision specific force,attitude,and carrier acceleration.The barometric altimeter was used to suppress the divergence of the altitude channel,and the gravity information could be obtained by the direct difference method.Then,the measurement accuracy of the four methods,namely,position(SINS/DR),velocity(SINS/OD),position velocity(SINS/DR/OD),and traditional SINS/GPS,was compared,and the influence of measurement selection on the measurement effect of the method proposed was analyzed.The results of repeated measurement line simulation and single measurement line vehicle experiment show that the method proposed can achieve fully autonomous vehicle gravity anomaly measurement,and it has general accuracy advantages over the traditional SINS/GPS method.In addition,the SINS/OD and SINS/DR/OD measurement accuracy is not much different and is better than the SINS/DR measurement method.