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高精度机电陀螺马达对轴承刚度有严格的配对要求;精确测控陀螺马达轴承的预载荷需要轴承刚度的准确数据作为计算依据。现有的仪表轴承刚度测量手段的精度太低,难以满足要求。在全面分析影响测量精度的原因基础上,研究出一套有效的办法,为提高我国机电陀螺仪表生产技术水平具有重要意义。 相似文献
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激光陀螺仪可以精确地确定运动物体的方位,但其自身机械振动影响其定位精度,稳定性与可靠性较差。提出了一种基于方差分析法的激光陀螺仪的机械抖动控制技术。设置一个弹簧阻尼系统,建立激光陀螺仪的机械抖动方程,对激光陀螺仪的正弦抖动信号进行分析,计算抖动轴的转角,利用laplace的变换和反变换计算激光陀螺仪零初值时和有初值时的抖动输出,并分析激光陀螺仪机械抖动控制的电路,在对激光陀螺仪建立机械动力模型和分析机械抖动电路的基础上,引入方差分析法,计算激光陀螺仪输出数据的速度,得出激光陀螺仪的抖动时间,分离激光陀螺仪中的误差源,最终实现激光陀螺仪的机械抖动控制技术。实验结果表明,提出方法可以有效控制激光陀螺仪的机械振动,提高激光陀螺仪的稳定性和可靠性。 相似文献
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陀螺仪球轴承,广义上系指作为各种陀螺仪表活动支承用的球轴承而言;然而,人们通常所称呼的陀螺仪球轴承,仅仅系指陀螺仪表中最重要的两种活动支承——高速转子球轴承和灵敏内、外框架球轴承(图1)。随着航空、航海事业中惯性导航技术的飞跃发展,陀螺仪表及其所用的球轴承性能和结构也有了巨大进步。目前,尽管滚动轴承的固有缺点——转子轴承的磨损和框架轴承的摩擦,使高精度陀螺仪表的发展受到了一定的阻碍。人们在探索新的方向,应用新的物理现象设计无高速转动的机械转子的新 相似文献
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用于贸易结算的蒸汽计量系统主要由计量仪表和远程抄表网络构成。对计量仪表的要求主要是仪表的可靠性和计量精度。对远程抄表网络的要求主要是网络稳定性和软件的可靠性。本文主要针对这些要求的实现进行探讨。 相似文献
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电子式多功能电度表的可靠性设计 总被引:1,自引:0,他引:1
电力工业的快速发展,对电能计量仪表的可靠性提出了更高的要求。本文简要介绍了电子式多功能电度表的工作原理、性能特点;详细从供电、测量、保护、监控四个环节叙述了多功能表的可靠性实现方法。 相似文献
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从分析基本可靠性 (R)和任务可靠性 (RM)的基本概念入手 ,并以某飞机为例 ,分别建立了任务可靠性模型和基本可靠性模型 ,并在假设系统寿命服从指数分布的基础上 ,计算了系统的基本可靠度和任务可靠度 相似文献
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对凸集不确定性和随机变量共存的结构混合可靠性模型行研究,以解决部分参量统计信息不足时的结构可靠性评定问题。基于Info-gap理论,建立一种统一的结构非概率可靠性模型,由此导出一种与概率可靠性方法等价的椭球非概率可靠性模型。用一种特定的椭球凸集模型描述随机变量不确定性,与一般性的凸集模型复合,将凸集不确定性和随机变量共存的混合可靠性问题统一为非概率可靠性问题。基于非概率可靠性方法,提出一种一般性的凸集-概率混合可靠性方法。给出的混合可靠性指标同时具有稳健可靠性和概率可靠性意义,可通过含约束的优化问题求解。算例分析显示,当数据分散性较强或较弱时,已有的混合可靠性方法不能有效度量结构可靠性,新方法更具合理性和适用性。 相似文献
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人机协同制造系统可靠性对系统的运行具有重要影响,在建立人机协同制造系统可靠性模型基础上,提出人机协同制造系统可靠性试验与评估方法.利用某人机协同制造系统可靠性增长试验中积累的可靠性试验数据,估算出系统目前的可靠性指标,研究结果表明,该方法在系统可靠性分析中合理可行. 相似文献
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Vahid Ebrahimipour S. M. Asadzadeh Ali Azadeh 《The International Journal of Advanced Manufacturing Technology》2013,66(9-12):1657-1672
A major challenge in reliability based optimal design problems is the evaluation of system reliability given a system design. Reliability evaluator is a tool, a model, or a system that analyses the reliability of a system given a specified system design. Reliability evaluator usually is embedded in reliability optimization model and it can be seen as a computational engine that can provide optimization model with the value of its objective function. Enhancing performance of the reliability evaluator in optimization models is important as the overall performance of optimization model is significantly affected by its embedded reliability evaluator. The purpose of this paper is to present an approach to improve the accuracy and generalization ability of evaluating system reliability in redundancy allocation problem. The main idea is to employ emotional learning-based fuzzy inference system (ELFIS) to improve performance of reliability evaluator. A series–parallel case reliability–redundancy allocation is considered and the proposed ELFIS is validated by comparison of its results with those of multi-layer perceptron neural network and adaptive network-based fuzzy inference system. Normalized mean squared error and mean absolute percentage error show that ELFIS can bring better accuracy in evaluating the system reliability for those reliability-based optimal designs. 相似文献
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机械系统的Bayes可靠性评估 总被引:4,自引:2,他引:2
讨论了机械系统的Bayes可靠性评估问题,当应力、强度均服从正态分布,且分布参数未知的情况下,首先分析了机械产品单元可靠性评估问题,讨论了给定验前分布情况下的单元可靠性Bayes精确下限,给出了无验前信息时的可靠性Bayes精确下限,鉴于精确限计算的复杂性,给出了应力-强度模型可靠性下限的近似计算方法,同时给出了可靠性的近似分布,然后把机械单元的可靠性信息折合到机械系统上,利用最大熵方法得到了系统可靠的验前分布,若没有做系统的可靠性试验,则根据此验前分布就可以对机械系统的可行性进行评估;若做了系统级可靠性试验,则利用Bayes公式求得系统可靠的验后分布,然后利用验后分布进行可靠评估,仿真实例说明机械系统Bayes可靠性评估的应用。 相似文献
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Young Kap Son 《Journal of Mechanical Science and Technology》2011,25(7):1717-1725
Reliability of an engineering system depends on two reliability metrics: the mechanical reliability, considering component
failures, that a functional system topology is maintained and the performance reliability of adequate system performance in
each functional configuration. Component degradation explains not only the component aging processes leading to failure in
function, but also system performance change over time. Multiple competing failure modes for systems with degrading components
in terms of system functionality and system performance are considered in this paper with the assumption that system functionality
is not independent of system performance. To reduce errors in system reliability prediction, this paper tries to extend system
performance reliability prediction methods in open literature through combining system mechanical reliability from component
reliabilities and system performance reliability. The extended reliability prediction method provides a useful way to compare
designs as well as to determine effective maintenance policy for efficient reliability growth. Application of the method to
an electro-mechanical system, as an illustrative example, is explained in detail, and the prediction results are discussed.
Both mechanical reliability and performance reliability are compared to total system reliability in terms of reliability prediction
errors. 相似文献
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Yi Pengxing Yang Shuzi Du Runsheng Wu Bo Liu Shiyuan School of Mechanical Science Engineering Huazhong University of Science Technology Wuhan China 《机械工程学报(英文版)》2005,18(4):519-524
Taking into account the whole system structure and the component reliability estimation uncertainty, a system reliability estimation method based on probability and statistical theory for distributed monitoring systems is presented. The variance and confidence intervals of the system reliability estimation are obtained by expressing system reliability as a linear sum of products of higher order moments of component reliability estimates when the number of component or system survivals obeys binomial distribution. The eigenfunction of binomial distribution is used to determine the moments of component reliability estimates, and a symbolic matrix which can facilitate the search of explicit system reliability estimates is proposed. Furthermore, a case of application is used to illustrate the procedure, and with the help of this example, various issues such as the applicability of this estimation model, and measures to improve system reliability of monitoring systems are discussed. 相似文献
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在可靠性度量中,除常见的随机不确定信息,还普遍存在着模糊不确定信息,因此在传统可靠性分析的基础上,基于模糊理论提出一种综合处理随机不确定信息与模糊不确定信息的可靠度计算方法,获得能同时处理概率密度函数与隶属函数的可靠度计算模型;并且在改进型证据理论的基础上对不同来源的可靠性信息进行融合处理,提出两种信息融合方式。研究结果表明,在随机性与模糊性并存的情况下,此可靠性度量模型能够较好地处理随机信息与模糊信息,所得结果有很高的准确性,并且能够动态地反映可靠度的计算机理;信息融合方法能够较好地处理不同来源的可靠性信息,对多源信息情况下的可靠度计算提供一种处理方法。 相似文献
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面向工业机器人系统的三种可靠度配置策略的研究 总被引:4,自引:4,他引:0
工业机器人的可靠性决定着它的应用前景及质量,而我国的工业机器人的可靠性并不容乐观,急需加以提高,针对这种情况,本文给出了三种有效的面向不同系统要求的工业机器人系统可靠度配置策略:"最小努力及比例"分配法适用于首次研制出来、已投入使用并准备进行产品生产,进一步提高其可靠度的工业机器人系统;"混联"分配法是一种简便易行的工业机器人系统可靠度分配方法,此方法适用于在无约束条件下进行研制新型工业机器人时,对其进行的系统可靠度分配,使得所研制的工业机器人具有较高的可靠性;"两级优化"分配是在有约束条件下的一种可靠度优化分配方法.这三种工业机器人配置策略的研究作为其可靠性设计中一个关键环节,不仅具有理论研究价值,同时具有重大的现实意义. 相似文献