【作者】 张正福；

【导师】 王安麟；

【作者基本信息】 上海交通大学 ， 机械设计及理论， 2007， 博士

【摘要】 近年来,由于微电子机械加工技术(MEMT, Micro-Electro-Mechanical Technology)的不断进步,微电子机械系统(MEMS)技术正在向实用化的方向发展。其中,微机械结构动态性能的健壮性问题就是MEMS实用化的一个关键问题之一。本论文以一种体微机械加工技术制备的音叉振动式微机械陀螺(以下简称为微结构或微陀螺)为研究对象,从微机械陀螺结构的动态性能健壮性问题出发,为了解决健壮性设计中微机械陀螺结构动态性能解析的高精度和计算时间的问题、提高其系统性能的稳定性,提出了基于子结构方法的微结构动态性能解析方法、灵敏度分析方法,基于Taguchi三次设计对微机械陀螺结构进行了健壮性设计方法的研究:1.在对微结构的基本工作原理和微结构的动态性能解析方法进行分析的基础上,为了解决微结构性能解析的高精度和计算时间的问题,提出了基于子结构方法的微结构动态性能解析方法。以一种音叉振动式微机械陀螺为研究对象,分析了微陀螺的动力学模型、空气阻尼特性以及弹性梁的设计;在微结构动态性能分析中,采用了动态子结构方法,建立了表征大自由度、复杂性的微结构解析方法。2.利用基于子结构的动态性能解析方法,分析微结构驱动和检测质量块的振动模态、幅频特性和瞬态特性,确定合理的驱动和检测质量块的振动模态,实现面向微结构最终输出性能的动力学特性与检测特性的分析。为提高微陀螺的动态性能,分析了不同的微陀螺弹性梁结构,进行了微陀螺弹性电容计算,对微陀螺的动态特性进行了解析,模拟并比较了微陀螺不同质量分布对微陀螺性能的影响。3.实现多物理场工作环境的表征和复杂动态性能的仿真,研究各种物理场单独效应以及多物理场耦合效应对微结构性能评价因子影响的灵敏度分析方法。为有效地进行微结构的动态优化设计与修改,基于子结构方法的微结构动态性能解析法和动态灵敏度分析理论,分析了微陀螺的几何尺寸和工作温度对其结构动态性能的影响。根据灵敏度分析计算结果,用正交试验优化方法进行了微陀螺的动态优化设计。4.为解决微结构加工工艺中的不确定因素造成产品性能的不稳定性问题,在分析微加工工艺引起的微陀螺性能变异的基础上,提出了基于Taguchi三次设计的微结构健壮性设计方法。考虑加工误差和工作温度变化的条件下,利用Taguchi的三次设计方法同结构参数仿真试验的动态子结构方法相结合,进行了微陀螺的健壮性设计。通过健壮性设计,获得工作温度变化和关键结构参数组合扰动下,系统性能指标变异最小的设计方案。对于由微结构的微小尺度效应带来的加工误差的不确定性和性能变异的难检测性等复杂问题,通过简单的健壮性设计修正其关键结构参数,实现极小化性能变异,提高性能稳定性,达到控制产品质量和性能的目的。5.为验证微结构动态性能解析理论以及理论分析结果的正确性,对音叉振动式微机械陀螺进行了实验研究,首先测量了微陀螺驱动模态和检测模态的频率特性,然后为验证微陀螺的工作环境对性能的影响,测量了工作温度在-40~85℃范围内变化情况下,微陀螺的性能变化特性。实验结果表明,理论分析结果与实验测试结果的趋势完全相同,基于子结构方法对微结构进行动态性能数值模拟与解析,能满足微陀螺设计与解析需要,并能找出性能最佳的结构设计值。通过对音叉振动式微机械陀螺结构动态性能解析与健壮性设计的研究,在微加工工艺误差和工作温度的变化情况下,减小了微机械陀螺结构动态性能的变异,提高了其系统性能的稳定性。本论文提出的研究内容不仅对微机械陀螺的研究有效,而且对其它微结构和复杂系统结构的动力特性研究都有重要应用价值。更多还原

【Abstract】 At present, with ceaseless improvement of micro-electro-mechanical technology (MEMT), development of the technology of the micro-electro-mechanical system (MEMS) tends to be directed forward its application in industrial branches.Especially, design and analysis of microstructure are one of the key technical projects. The demands of not only complexity and environmental applicability of MEMS, but also those of the measuring accuracy, the responding velocity and stability of microsensors are higher and higher.Therefore, the research on the analysis of the dynamic performance based on the substructuring method has a great significance in the improvement of MEMS technology and is necessary to its further development.This paper aims to improve the stability of the dynamic performance from the viewpoint of the demand of the special performance of microstructure.For this, a silicon bulk micromachined tuning fork vibratory gyroscope has been taken as the research object of this paper, and the method for analysis of the dynamic performance of the microstructure has been described in detail.Based on understanding the basic principle of the microstructure and several methods for analysis of the dynamic performance of the microstructure, this paper has suggested the introduction of the analysis method for dynamic performance of microstructure based on substructure method into the research for resolving some problems encountered in the analysis of the performances of microstructures, e.g. improvement of the accuracy and shortening of the calculating time.This paper has also discussed the analyses of the dynamic mechanical model of the micromachined gyroscope, air damp characteristic and the design of the elastic bar; especially, the dynamic substructure method has been applied to analysis for the dynamic performance of the microstructure and the analysis method for the microstructures with great degrees of freedom and complexity has been realized.2. In this paper, the vibration modes for the driving and measuring block of the microstructure, frequency response and real time characteristics have been analyzed by using analysis method for dynamic performance of the substructure.The reasonable vibration modes for the driving and measuring masses have been found and the analyses of the dynamic mechanical characteristics and the measuring properties for the last output performances of the microstructures have been realized.In order to improve the dynamic performances of micromachined gyroscopes, their different elastic-bar structures have been analyzed and the detection capacitance of the micromachined gyroscope has been calculated; the analysis of the dynamic characteristics of the microgyroscope has been carried out; the influence of different mass distributions of the microgyroscope to its performances has been simulated and compared with one another.3. In this paper, the characterization of working environments for multi-physical fields the simulations of the complex dynamic performances have been realized; the analysis method for sensitivity has been studied, which is necessary to evaluate how the single effect and the synergetic effect of the multi-physical fields influence the factors estimating the performances of the microstructureIn order to effectively perform the dynamic optimum design and modification of the microstructure, the influence of the geometrical dimensions and the working temperature to its dynamic performances has been analyzed by the analysis method for the dynamic performances of the microstructure based on the substructure method.Based on the results of the sensitivity calculation, the methodology of the orthogonal experiment optimization has been used to carry out the dynamic optimum design of micromachined gyroscope.4. In order to solve the instability of the performances of products caused by some uncertain factors in the processing techniques, the robust design method for the microstructure based on Taguchi three-stage design has been suggested based on the analysis on the variation of the performance of the micromachined gyroscope caused by processing techniques.Considering the processing errors and the temperature change, Taguchi design method has been used in combination with the dynamic substructure method in the simulation test of the structural parameter to perform the robust design of the micromachined gyroscope.Through the robust design, the optimum design scheme able to realize the minimization of the variance of the system performance under the synergistic influences of temperature variation and key structural parameters ahs been proposed.The microscale dimensions of microstructures can cause uncertain processing errors and difficulties of their performance variations.In this paper, the well-known robust design method has been introduced into determining the key structural parameters in order to ensure the minimum variation of the performance and to improve the stability of the performance from the viewpoint of controlling the qualities and the performances of products.5. In order to characterizing the analysis theory of the dynamic performance of the microstructure and to ensure the accuracy of the theoretical analysis, the experimental research ahs been performed on the tuning fork vibratory micromachined gyroscope; First of all, the frequency responses of the driving and measuring modes of the micromachined gyroscope have been measured; Second, the performance variation of the microgyroscope has been measured in the working temperature range -40℃to 85℃to demonstrate the influence of the working environment of the microgyroscope to its performance.The experiment results have shown that the results of theoretical analysis and measurement are found to be quite consistent with each other and that the numerical simulation and analysis for the dynamic performance of the microgyroscope based on the substructure method can satisfy the demands of the design and the analysis of the microgyroscope and also allow us to find out the optimum parameter values for designs of structure and performance.更多还原