Mechanical Thermal Noise in Micro-Machined Levitated Two-Axis Rate Gyroscopes
Mechanical Thermal Noise in Micro-Machined Levitated Two-Axis Rate Gyroscopes
复制标题
DOI：
10.1109/jsen.2017.2785859
复制
发表时间：
2018-02-15
影响因子：
4.3
通讯作者：
Badilita, Vlad
中科院分区：
文献类型：
--
作者：
Poletkin, Kirill V.;Korvink, Jan G.;Badilita, Vlad
本文对微机械悬浮两轴速率陀螺仪（MLG）中的机械热噪声进行了全面研究。考虑到 MLG 中采用的陀螺性质和电磁悬浮类型，获得了对应于正和负角位置刚度的两种情况的有效阻尼系数。根据获得的系数，推导了陀螺仪本底噪声谱密度及其角度随机游走的表达式。此外，对理想悬浮陀螺仪对整个频域内脉动扭矩的响应的研究表明，为了保持相同的角位置刚度，对测量速率的检测进行了限制。这种响应是约翰逊噪声的一种形式，它解释了陀螺仪分辨率的限制机制，而陀螺仪分辨率又限制了悬浮陀螺仪的当前性能。此外，使用伊辛准则，可以获得估计分辨率的替代定性方法。通过结合约翰逊噪声和伊辛准则技术，提出了陀螺仪分辨率的置信范围。
In this paper, mechanical thermal noise in micro-machined levitated two-axis rate gyroscopes (MLG) is comprehensively studied. Taking into account the gyroscopic nature and a type of electromagnetic levitation employed in MLG, effective damping coefficients are obtained for two cases corresponding to positive and negative angular position stiffness. According to obtained coefficients, expressions for the spectral density of the gyroscope noise floor and its angular random walk are derived. Moreover, an investigation of the response of an ideal levitated gyroscope to the fluctuating torque within the entire frequency domain shows a restriction of the detection of the measuring rate in order to preserve the same angular position stiffness. This response, a form of Johnson noise, provides an explanation of the mechanism of constraints in gyroscope resolution, which in turn limits the current performance of levitated gyroscopes. Also, using the Ising criterion, an alternative qualitative means to estimate the resolution is obtained. By joining the Johnson noise and Ising criterion techniques, a confidence range for the gyroscope resolution is proposed.