【作者】 王浩；

【导师】 常洪龙；

【作者基本信息】 西北工业大学 ， 微机电系统及纳米技术， 2022， 博士

【摘要】 智能武器、微型航天器等高端装备对MEMS陀螺的性能提出了很高的要求;同时不同应用对MEMS陀螺的量程、带宽、精度等指标也提出了不同的需求,例如战术机器人对陀螺的带宽要求较高,微小卫星对陀螺的测量精度要求较高,而制导弹药对陀螺的量程要求较高。针对不同的应用需求,往往需要进行MEMS陀螺的定制化设计,导致重复设计严重、设计周期长、综合设计成本高。针对以上问题,论文首先设计一款高精度MEMS多环谐振陀螺,然后基于高精度MEMS多环陀螺开展指标可重构设计方法的研究,使MEMS陀螺在完成加工后能够进行惯性指标的调整,从而可以有效地避免针对不同应用需求的MEMS陀螺的重复设计。具体内容包括:(1)提出了一种具有全电极填充的MEMS多环谐振陀螺敏感结构,并设计了一种基于参数可调的ASIC的陀螺闭环检测系统,实现MEMS陀螺的闭环驱动与闭环检测。建立了ASIC和MEMS多环谐振器的数学模型,对MEMS陀螺闭环系统进行了机电一体化建模和仿真,为指标可重构技术的研究以及自顶向下的MEMS陀螺敏感结构设计奠定了基础。(2)提出了一种闭环MEMS陀螺的指标分解方法,研究了MEMS陀螺指标可重构设计方法。对陀螺闭环系统中典型的非线性串行模块“调制器—陀螺二阶系统—解调器”进行了降阶处理,将其等效为线性模块,使陀螺闭环系统中的非线性环路转换为线性系统;推导出陀螺的角速率闭环传递函数以及等效噪声传递函数,建立了陀螺的带宽、量程、标度因数、精度等指标与闭环系统参数、敏感结构参数的数学关系。最后,利用ASIC的参数可配置能力,完成了基于传递函数参数配置的惯性指标可重构设计方法的研究,使MEMS陀螺能够实现带宽、量程、标度因数、精度等指标的可重构设计。(3)提出了一种自顶向下的MEMS多环陀螺敏感结构设计方法。通过有限元仿真,建立了三维尺寸与陀螺敏感参数的关系,并基于指标分解方法,分析了三维尺寸参数对机械噪声、机电灵敏度、科氏力增益等陀螺性能参数的影响规律,形成了一种高精度MEMS多环谐振陀螺的结构设计方法。设计了一款内嵌全差分电极的MEMS多环陀螺结构,并通过对电极图形的优化、三维尺寸的设计,使结构具备优异的检测灵敏度和更小的机械噪声。同时,对MEMS陀螺在加工过程中两种常见的非理想效应—“信号馈通效应”和“频率裂解”—进行规避设计,并基于Cavity＿SOI工艺完成了MEMS多环谐振陀螺的加工。(4)完成了指标可重构的MEMS多环谐振陀螺的测试与验证。MEMS多环陀螺在量程为±300°/s、带宽为100Hz的情况下,零偏不稳定性达到0.25°/h;全温(-45℃～85℃)零偏不稳定性达到0.5°/h。同时,通过ASIC电路的参数配置,实现了量程从±300°/s到±3750°/s、带宽从20Hz到200Hz、标度因数从2151 LSB/(°/s)到26890 LSB/(°/s)的指标可重构设计,验证了带宽、量程、标度因数的可重构设计方法以及精度的优化方法。基于以上研究,论文完成了一款指标可重构的MEMS多环谐振陀螺的设计,其精度满足战术级指标要求,且具备带宽、量程、标度因数以及精度等指标的可重构设计能力。MEMS多环谐振陀螺通过指标可重构设计,覆盖了高带宽陀螺、大量程陀螺和高精度陀螺等三种典型的MEMS陀螺指标,可以分别满足战术机器人、制导弹药和微小卫星等典型应用场景的需求。更多还原

【Abstract】 High-end applications put high requirements on the performance of MEMS gyroscopes.Meanwhile,different application scenarios have different requirements for the accuracy,measurement range,and bandwidth of MEMS gyroscopes.For example,the tactical robots have higher requirements on the bandwidth;the microsatellites have higher requirements on the accuracy;while the guided munitions have higher requirements on the measurement range.In order to adapt to different application requirements,it is often necessary to customize the design of MEMS gyroscopes,resulting in serious repeated design,long design cycle,and high design cost.Aiming at above problems,this thesis proposes a design method of an indicator reconfigurable MEMS gyroscope.Through the indicator reconfiguration design,the inertial indicators of MEMS gyroscope can be configured after manufacturing,so that the repeated design for different application requirements can be effectively avoided.The main contents include:(1)A MEMS disk resonator gyroscope(DRG)filling with full electrodes is proposed,and a configurable-ASIC-based gyro closed-loop system is designed to realize the closed-loop driving and closed-loop sensing.The mathematical models of ASIC and MEMS DRG are established,and the mechatronics modeling and simulation of the closed-loop system is carried out,which lays the foundation for the research on the indicator reconfigurable technology and the top-down MEMS gyroscope resonator design.(2)An indicator decomposition method of closed-loop MEMS gyroscope is proposed.The closed loops in the mechatronics model of MEMS gyroscope are linearized or order-reduced to linear models,so that the complex and nonlinear closed-loop system is transformed into a linear system.The transfer functions of all closed loops are derived,as well as the noise transfer functions.The mathematical analysis formulas between the inertial indicators and the sensitive parameters are obtained.Finally,the indicator reconfiguration method is studied,so that the MEMS gyroscope has the capability of precision optimization and indicator reconfiguration design based on the configurable ASIC,including bandwidth,measurement range and scale factor.(3)A top-down MEMS DRG design method is established.Through the finite element simulation,the relationship between the three-dimensional parameters and the sensitive parameters is obtained,and the influence of the three-dimensional parameters on the performance parameters,such as mechanical noise,electromechanical sensitivity,and Coriolis force gain,is analyzed and summarized,so that a high-precision MEMS DRG design method is formed.A MEMS DRG with fully embedded differential electrodes is designed.After the optimization of electrode pattern and the design of three-dimensional size,the resonator does well in detection sensitivity and mechanical noise.Meanwhile,the avoidance design of two common non-ideal effects during manufacturing—“signal feedthrough effect”and“frequency splitting”—is completed.At last,the MEMS DRG is fabricated by Cavity＿SOI process.(4)The test and verification of the reconfigurable MEMS DRG is completed.The bias instability reaches 0.25°/h under the condition of±300°/s measurement range and 100Hz bandwidth.The full-temperature(-45℃～85℃)bias instability is 0.5°/h.Meanwhile,the MEMS gyroscope has achieved the indicator reconfiguration design of a measurement range from±300°/s to±3750°/s,a bandwidth from 20Hz to 200Hz,and a scale factor from 2151LSB/(°/s)to 26890 LSB/(°/s),which verifies the reconfiguration design method of bandwidth,measurement range,scale factor and the accuracy optimization method.Based on the above research,this thesis completes the design of a reconfigurable MEMS DRG whose accuracy meets the tactical-level indicators.And the MEMS DRG has reconfigurable design capabilities of bandwidth,measurement range,scale factor,and accuracy.After reconfiguring design,the MEMS DRG could cover three typical MEMS gyroscope indicators including high-bandwidth gyroscope,large-measurement-range gyroscope and high-precision gyroscope,which can meet the requirements of tactical robots,guided munitions and microsatellites,respectively.更多还原