通过模拟测量错误,对三轴加速器属性的基于重力的确定进行B型不确定性分析
1National Institute of Standards and Technology, Gaithersburg, MD 20899 USA.
概括
这项研究量化了三轴加速度计校准中的错误,原因是杆和旋转步骤大小的不准确性. 结果为灵敏度矩阵组件和内在性质提供了不确定性边界,这对于精确的加速度计测量至关重要.
科学领域:
- 计量学和仪器仪表技术
- 传感器技术 传感器技术
- 校准和测量科学 校准和测量科学
背景情况:
- 三轴加速度计对于惯性导航和运动传感至关重要.
- 校准准确度至关重要,但受到系统缺陷的影响.
- 之前的研究建立了测量协议,但缺乏针对特定校准设置的详细错误分析.
研究的目的:
- 模拟和量化杆对齐和旋转步骤大小错误对三轴加速度计校准的影响.
- 为了确定校准系统缺陷对灵敏度矩阵和内在性质测量的影响.
- 根据模拟的错误源,将B型不确定性分配给校准参数.
主要方法:
- 在双轴校准系统中模拟杆对齐和旋转步骤大小错误的效果.
- 集成的模拟加速度计轴非直角性和非相同的灵敏度.
- 利用之前描述的测量和分析协议进行错误传播.
主要成果:
- 标准不确定性的估计上限:~1x10−5 (内在的灵敏度),~2x10−5 (对角敏感度矩阵元素),~5x10−5 (非对角元素) 和~2x10−4 (零加速偏移).
- 在~5x10−3度估计的内在角度不确定性.
- 灵敏度矩阵错误归因于校准系统的构建和安装,而不是模拟的加速度计缺陷.
结论:
- 该研究提供了三轴加速度计校准参数的定量不确定性估计.
- 结果对于在计量应用中分配B型不确定性是有价值的.
- 这些发现支持使用精心制造的多轴旋转阶段来进行可靠的加速度计表征.
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