We present an in situ calibration process to derive the transient behavior of the offsetting fluxgate magnetometer (MGF) instruments on the Cassiope spacecraft. The dynamic behavior of the MGF changed on orbit following a software update. Characterizing the new instrument dynamics during normal spacecraft operations and then removing the transients was confounded by significant magnetic interference from the reaction wheels used to orient the spacecraft. Special operations were performed where data were taken in a safehold mode, with the reaction wheels stopped, following a single-event upset of the spacecraft bus flight computer after transiting the South Atlantic Anomaly. The slow single-axis rotation of the safehold mode was used to characterize the fluxgate's new feedback dynamics. This characterization process was then adapted for routine operation intervals with slow reaction wheel rates to allow the transient behavior to be characterized over long intervals of data spanning a wide range of temperatures. Subtracting these characterized transients from the flight data improves the instrument's noise floor and allows the instrument to accurately track rapidly changing local fields without loss of measurement fidelity. More generally, this characterization process should apply to other situations where the dynamics of an offsetting instrument must be calibrated in situ.

中文翻译：

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在仙后座飞船上对偏移的磁力计反馈瞬变进行原位校准

我们提出了一种现场校准过程，以得出仙后座飞船上的偏置磁通门磁强计（MGF）仪器的瞬态行为。软件更新后，MGF的动态行为在轨道上发生了变化。由于用于定向航天器的反作用轮产生了明显的电磁干扰，因此在正常航天器运行过程中表征新仪器的动力学特性，然后消除瞬变现象是令人困惑的。在穿越南大西洋异常之后，航天飞机客车飞行计算机发生了一次单次失误之后，进行了特殊操作，其中数据以安全保持模式进行了采集，反作用轮停止了。安全保持模式的缓慢单轴旋转用于表征磁通门的新反馈动态特性。然后，该表征过程适用于具有慢反作用轮速率的常规操作间隔，从而可以在跨越宽温度范围的较长数据间隔内表征瞬态行为。从飞行数据中减去这些特征瞬变可改善仪器的本底噪声，并使仪器能够准确跟踪快速变化的局部场，而不会损失测量保真度。更一般而言，此表征过程应适用于其他情况下，必须对偏移仪器的动力学进行原位校准。从飞行数据中减去这些特征瞬变可改善仪器的本底噪声，并使仪器能够准确跟踪快速变化的局部场，而不会损失测量保真度。更一般而言，此表征过程应适用于其他情况下，必须对偏移仪器的动力学进行原位校准。从飞行数据中减去这些特征瞬变可改善仪器的本底噪声，并使仪器能够准确跟踪快速变化的局部场，而不会损失测量保真度。更一般而言，此表征过程应适用于其他情况下，必须对偏移仪器的动力学进行原位校准。