一种免装配微惯性测量单元的研制与开发

Development of a free-assembly micro inertial measurement unit

以柔性材料和高精度六面体作为惯性传感器的安装载体和基准,设计了一种免装配、安装误差小、体积小、功耗低且便于标定的微惯性测量单元。给出了安装误差小角度前提下的传感器的测量方程和标定方法;利用微控制器的并行工作机制,提出了一种快速有效的基于均值滤波和FIR滤波的组合滤波方案。实验结果表明:MIMU可以100 Hz的频率更新测量输出,加速度测量噪声小于2.5 mg、测量误差小于0.8 mg,旋转角速度测量噪声小于0.15 o/s、测量误差小于0.2 o/s,可满足微小型惯性导航系统的功耗、体积、测量精度和响应速度的应用需求。

In this paper,a free-assembly,small-installation-error,small-size and easy-calibration micro inertial measurement unit（MIMU） is developed,in which the flexible material and the high-precision hexahedron are used as carrier and reference respectively for mounting inertial sensors.Measurement equations and calibration methods for the sensors are proposed on condition that misalignment angles are small.According to the concurrency of the microcontroller,a high-speed,effective combinational filter based on average filter and FIR filter is designed.Experiment results show that the MIMU can update the measurement output at the rate of 100 Hz,the noise and the error of acceleration are less than 2.5 mg and 0.8 mg respectively,and the noise and the error of angular velocity are less than 0.15°/s and 0.2°/s respectively,which are acceptable for the micro inertial navigation system.