制造特性对液浮陀螺仪组件应力状态影响研究

发布时间：2018-06-26 12:01

本文选题：液浮陀螺仪 + 应力状态　；参考：《北京理工大学》2014年博士论文

【摘要】：作为惯性导航系统中的关键仪表之一，液浮陀螺仪在我国国防领域起着至关重要的作用。目前在我国液浮陀螺仪等一类精密机械系统的装配过程中，常常会出现所有的零件加工精度都满足设计要求，但装配后精度与稳定性却不高的现象。究其原因主要是零件的制造特性与系统精度之间的关系尚无有效的定量分析方法。而系统的精度与稳定性很大程度上受到了零组件装配之后的应力状态的影响。因此，本文以某型液浮陀螺仪为研究对象，从零件表面形状误差建模入手，研究表面形状误差等制造特性对液浮陀螺仪零组件应力状态的影响机理，探索建立液浮陀螺仪零组件制造特性与系统工作精度关系的定量分析方法。本文首先论述了开展液浮陀螺仪零组件制造特性与应力状态影响研究的目的与意义，然后就国内外相关领域的研究现状与方法进行了综述与总结。针对目前液浮陀螺仪等一类精密机械系统精度及稳定性研究中存在的问题，开展了如下研究：（1）以平面形状误差为研究对象，开展了表面形状误差建模研究。根据表面形状误差测量数据，利用离散余弦变换构建基形状向量，建立了基于基函数线性相加的表面形状误差模型。然后利用该方法对二维、三维配合实例进行了形状误差建模，验证了模型的正确性。在形状误差建模之前先对测量数据进行样条插值处理，能够极大提高形状误差的建模精度。（2）在考虑表面形状误差的基础上，提出了分析带有表面形状误差的平面配合面接触状态的改进差表面法，通过理论分析与实验研究了装配时配合面的形状误差对零件接触状态的影响情况。依据逆向工程思想，根据零件几何形状误差的测量数据建立带有误差的三维几何模型，通过数值仿真和实验研究验证了所提方法的有效性。（3）研究了液浮陀螺仪中浮子的制造特性对其应力状态的影响。基于流体力学、流固耦合动力学有关理论建立了液浮陀螺仪中流体的运动方程，并由此推导得到浮子表面的受力情况。再基于计算流体动力学通过有限体积法对流体运动以及浮子受力进行了仿真分析，设计并开展了不同粗糙度条件下浮子表面受力与液浮陀螺仪零位信号实验研究。（4）在考虑液浮陀螺仪零组件的制造特性的前提下，开展了温度场变化对液浮陀螺仪组件应力状态及变形的影响研究。基于传热学以及热-结构耦合基本理论，通过数值仿真方法分析了液浮陀螺仪在温度变化时温度场分布及其引起的热应力情况。在考虑液浮陀螺仪零组件的制造特性的前提下，分析了温度场作用对液浮陀螺仪关键零组件应力状态与变形的影响。（5）研究了不同制造特性对液浮陀螺仪装配时应力状态影响情况。针对五套液浮陀螺仪，，通过有限元法从形状误差、相对位置、预紧力三个方面研究液浮陀螺仪零组件制造特性对其应力状态与变形的影响情况，并依据单因素法对应力状态和变形灵敏度进行了定性分析，获得不同制造特性对液浮陀螺仪应力状态的影响情况。
[Abstract]:As one of the key instruments in inertial navigation system , the liquid - float gyroscope plays an important role in the defense field of our country . At present , in the assembly process of a kind of precision machinery system , such as liquid - float gyroscope in China , all parts processing precision can meet the design requirements . However , the accuracy and stability of the system are largely influenced by the stress state after the assembly of the components . Therefore , the paper studies the influence mechanism of the manufacturing characteristics of the surface shape error on the zero component stress state of the liquid - floating gyro , and explores the quantitative analysis method of the relationship between the manufacturing characteristics of the zero component of the liquid - floating gyro and the system working accuracy .

In this paper , the purpose and significance of the research on the influence of the manufacturing characteristics and the stress state of the zero component of the liquid - float gyroscope are discussed firstly , and then the present situation and method of the research on the relevant field of the liquid - floating gyroscope are summarized and summarized . The problems existing in the research of precision and stability of the precision machinery system such as the liquid - floating gyroscope are studied as follows :

( 1 ) Based on the surface shape error measurement data , a surface shape error model based on the linear addition of the basis function is established by using the discrete cosine transform to construct the base shape vector . Then the shape error model is modeled by using the method to model the shape error of the two - dimensional and three - dimensional matching example .

( 2 ) On the basis of considering the surface shape error , the paper presents an improved differential surface method for analyzing the contact state of the plane with the surface shape error . Based on the theory analysis and experiment , the influence of the shape error of the mating surface on the contact state of the part is studied . According to the reverse engineering idea , a three - dimensional geometric model with error is established according to the measurement data of the geometric shape error of the part , and the validity of the proposed method is verified by numerical simulation and experimental study .

( 3 ) The influence of the manufacturing characteristics of the float in the liquid - float gyroscope on its stress state is studied . Based on the theory of fluid mechanics and fluid - solid coupling dynamics , the motion equation of the fluid in the liquid - float gyroscope is established , and the stress of the surface of the float is deduced . Based on the computational fluid dynamics , the fluid motion and the force of the float are simulated and analyzed by the finite volume method , and the zero - position signal experiment of the float surface under different roughness conditions is designed and carried out .

( 4 ) The influence of temperature field change on the stress state and deformation of the liquid - float gyroscope component is studied under the precondition of considering the manufacturing characteristics of the zero component of the liquid - float gyroscope . Based on the theory of heat transfer and thermal - structural coupling , the temperature field distribution and the thermal stress caused by the liquid - float gyroscope are analyzed by numerical simulation method .

( 5 ) The influence of different manufacturing characteristics on the stress state of the liquid - floating gyroscope is studied . The influence of the manufacturing characteristics of the zero component of the liquid - float gyroscope on the stress state and deformation is studied by finite element method from three aspects of shape error , relative position and pre - tightening force , and the influence of different manufacturing characteristics on the stress state of the liquid - floating gyroscope is obtained .
【学位授予单位】：北京理工大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TN96

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