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英文部分Study of electro-hydraulic feed System of Hydraulic Roof Bolter based on fuzzy reliability theoryHuang Zizhai,Zhao JingyiHebei Key Laboratory of Heavy Machinery Fluid Power Transmission and Control, Yanshan University, Qinhuangdao, HebeiAbstract: Based on the theory of fuzzy mathematics to describe working conditions of the system, which combined with experiments, to be a calculation method with membership function of normal distribution. It was closer to the actual conditions, so as to ensure system reliability. To introduce construction conditions and performance characteristics of electro-hydraulic feed System of Hydraulic Roof Bolter, and connected with experiment data of practical construction, the feasibility of research method was verified.Keywords: Fuzzy Reliability; Hydraulic Roof Bolter; The Electro-hydraulic System; Normal DistributionI. INTRODUCTIONElectro-hydraulic system is a key part of construction machinery. Now, electrical and hydraulic is more and more closely integrated, it is necessary to study the integrated reliability of the system with the part of electric control1. And the key factor to guarantee normal working of Hydraulic Roof Bolter is higher reliability of electro-hydraulic system. But, the system from normal to failure shows many the states of transition. And it is often so difficult to use accurately numeric to describe the probability of reliability. It is more scientific and rational way, with fuzzy theory, to solve the problems of fuzzy reliability between totally invalid and completely normal 2.Hydraulic Roof Bolter is a important equipment in rock bolting. It is applied to improve ability of laterally loaded in dam foundation, pile foundation, retaining wall, slope treatment, and deep foundation pit (Fig.1). For using electro-hydraulic feed System, the unfavorable factors were heavy and complexity load, long work time, frequent fro movement and adverse working environment etc. So the failure rate was high.Figuer.1 Hydraulic Roof BolterII. THE CALCULATION METHOD OF FUZZY RELIABILITYA. The definition of fuzzy reliability of componentsFor independent components in system, it was described as i (i = 1, 2,3, n). The inherent performance indexes were rated pressure, voltage, flow and current etc, which were discrete random variable. It was expressed as S . The function indexes in system were tempera-ture and humidity, pressure, voltage, flow and current of system and cleanliness of oil etc, which were discrete fuzzy variable. It was expressed as . The formula of fuzzy reliability of components was: (1)Where, -the value of the i th inherent performance index of component i (i =1,2,3, n)- the i th value of function index of component i (i =1,2,3, n)- the probability of the i th inherent performance index of the n th component- the subordinate function of the i th function index of the n th component- the subordinate function of the i th function index of the n th component in thresholdThe f was worked out by fuzzy component failure rate, its calculation formula was: (2)B. The Calculation Model of Fuzzy ReliabilityThe method of L A Zadeh is: (3)Where, the did not expressed fraction, but expressed a corresponding relation from (elements in universe ( U) to (membership function). And the“+” was not summation but signs integral of fuzzy set in universe U . For failure series system, the system was normal when every component was normal working, otherwise, it was failure. To set the U was real number field, and the was fuzzy reliability of system that was approximately normal working. That was:Where, - the fuzzy reliability of the i th component- the number of components The general calculation method was that set the U as real number field, and the as fuzzy reliability of component that was approximately normal working.Fig.2 linear representationThat was:Where, : the mean of the fuzzy number : the lower confidence limit: the upper confidence limitThe linear representation of it is:If the function of and the function of were linear, the was 1. If the variable was or , the was 0. If it was in , was .If the was more closely , the was more closely 1.By the calculation method used normal distribution，the general calculation method was simple and easy3. But the sample space of failure probability of many components was accord with normal distribution. So the calculation method was used by normal distribution that was accurate and reasonably.To set the U was real number field, and thewas fuzzy reliability of component that was approximately normal working. That was: Where, : the mean of the fuzzy number : the lower confidence limit: the upper confidence limitFig.3 the normal distributionTheandwere obtained by calculation of interval estimation of normal distribution, the calculation formula was:Where, : the unbiased estimation of 、:the percentile value of standard normal distribution：the confidence level：the value is obtained by different components parameter：the number of sample As stated above, the confidence interval was：Namely：The number of was corresponding to the 1 of membership degree.If , assumed the membership degree was 0.If ，the membership degree was .The was:III. THE CALCULATION OF FUZZY RELIABILITY OF ELECTRO-HYDRAULIC FEED SYSTEM OF HYDRAULIC ROOF BOLTERThe study calculation was a example by electro-hydraulic feed System of Hydraulic Roof Bolter.The feed System that was the longest work time was in the electro-hydraulic of Hydraulic Roof Bolter. That was favorable factor for the calculation.Fig.4 structure diagram of Hydraulic Roof BolterFig.5 structure diagram of feed SystemFig.6 The Electro-hydraulic System LogicThe electro-hydraulic feed System of Hydraulic Roof Bolterwere formed with variable pump (I1), gear pump(I2), oil handle(I3), proportional valve(I4), pressure sensor(I5),controller(I6), unravelcylinder(I7). Fig.5. The unravel cylinder drove the power head to unravel and fallback. The construction process of the system was: the first, for drilling, the unravel cylinder provided power to overcome load. The load was large and several variable. The second, for adding pipe, the worker needed to add the other pipe after drilling in a pipe for the demand of depth. For clamping the pipe by fixture, providing overcome power by cylinder to shackle, driving the power head on start point and connecting pipe, the process was accomplished. The third, for drawing water slag discharge, which was needed slag discharge by water into enough depth. The crushed stone and soil was exhaust with water by fro movement of inside drill rod. The inside drill rod was drove by unravel cylinder, which was linked together the power head. For pulling out pipe, the process was opposite to adding pipe, when the construction of the one of borehole. But the load was largest and the pressure was highest.For electro-hydraulic feed System, the system was normal when every component was normal working, otherwise, it was failure. So that was failure series system, which were composed of seven components.As stated above, obtain the fuzzy number of the i th component. That was:When two components were in the system:Then, n components were in the system, deducing the calculation formula:The calculation of fuzzy reliability of electro-hydraulic feed System of Hydraulic Roof Bolter was: Fig.7 experiment in workshopFig.8 experiment in construction siteWith the maintain and repair work eight-hour records each day for ten months, to every work week for the cycle, collecting pressure, temperature and other signals, obtained the necessary experiment data. By applying the data provided by manufacturer, reference documents and experiment, the of every component was obtained. And it was into equation from (6) to (9), calculating out the value of and. Such as:Tab-1The value of tab-1induced into (12) calculating to obtain that:Fig.9 the failure componentsThe results showed that the fuzzy reliability was 0.72817, the membership degree was 1, when the electro-hydraulic feed System of Hydraulic Roof Bolter was working. The reliability of the system was among 0.55024 and 0.90526. In other words, the probability of the value of reliability of the system was about normal distribution.IV. ConclusionsTo comparatively completely describe the changing rules of the reliability of the electro-hydraulic feed system on the basis that fuzzy theory and reliability theory. The calculation method with membership function of normal distribution was proposed, with tracking experiments, that the result was dependability and accuracy. To introduce construction conditions and performance characteristics of electro-hydraulic feed System of Hydraulic Roof Bolter, and connected with experiment data of practical construction, the feasibility of research method was verified. Then, the analysis method was showed effective to study reliability for the electro-hydraulic feed system of Hydraulic Roof Bolter, and providing the scientific theory reference for the reliability design and failure diagnosis which is more and more nowadays.REFERENCES1 Zhao Jingyi; Yao Chengyu. Progress of reliab- ility research on hydraulic system J. Hydraulics Pneumatics & Seals, 2006(3):50522 Zhao Jingyi, Guo Rui and Wang Zhiyong. The developing of independent suspension and its electro-hydraulic control system of heavy platform vehicle. Journal of Northeastern University, 2008, vol.29, pp237-2403 Guo Rui, Li Na, Zhao Jingyi. Design and Development of SPC90 Slag Pot Carrier of Large Steel Slag TransportationSpecial Device for Steel Mills. 2010 WASE International conference on Information Engineering. Beidai River, China, 2010, pp320-3234 Wang Peizhuang. Fuzzy Set Theoryand its App- licationM. SHANGHAI SCIENCE & TECH- NOLOGY PUBLISHINGHOUSE , 1983.5 Xu Yaoming. The Basis of Hydraulic Reliability Engineering M. HARBIN INSTITUTE OF TE- CHNOLOGY PRESS.1991.New generation automated drilling machine for tunneling and underground mining workJacek KarliskiAbstract：Selected problems of designing a new generation automated drilling machine for tunnelling and underground mining work are presented. The requirements needed to build a machine of this class were identified and collected. An original concept of the self-propelled drilling machine was developed. A virtual model of the machine was created and subjected to different numerical cases of loading. FEM strength calculations of the load- bearing structures were carried out. All the machines work operations have been fully automated. The result is a new original automated drilling machine.2007ElsevoerB.VAll righrs reserved.Keywords: FEM; Drilling machine; Mining1. Introduction Drilling machines find application in tunnelling and mining excavation. Such machines must be functional and meet user expectations. A new original automated modular drilling machine shown in Fig. 1 is proposed.Depending on the model, the Self-Propelled Mining Machine can be used to drill shot holes or anchor holes. All its types and varieties have an identical complete tractor and afront platform (Fig. 1) and differ mainly in the work booms and their attachments. The new generation drilling machines intended use is roof bolting or (after retooling and hydraulic system modification) shot hole boring in tunnelling and underground mining excavation. Fig. 1. Self-propelled modular drilling machine with two booms. The drilling machine consists of a universal tractor, a front platform with an operator protecting structure and a straight-line boom to which different work tools can be attached. The machine can fit expansion and adhesive anchors with a length of 1.82.6 m and a diameter of 2838 mm and drill shot holes 4576 mm in diameter and up to 4340 mm long. Thanks to the load-sensing hydraulic system equipped with ergonomic joysticks the work tools can be quickly reset and the hydraulic feed can be quickly adjusted to the power demand of the drifter drills boring shot holes or anchor holes. The modern hydrostatic drive unit allows the machine to negotiate longitudinal elevations at an angle of up to 12in underground excavations and ensures flexible transfer of drive from the combustion engine to the road wheels. Meeting all the noise and exhaust cleanliness the drive unit ensures excellent ergonomic conditions for the operator during driving. Since the operator will work in very difficult environmental conditions, i.e. at high ambient temperatures (above 35 C), high humidity (around 95%) and in enclosed areas with limited air movement (mine faces), the machine should be equipped with an air-conditioned ergonomic cabin. The machine has an original straight-line boom (Fig. 2) rotatable by 360 whose kinematics enables boring parallel holes in mining excavations 35 m2 in cross-section and roof bolting in 7.5 m wide and 7.0 m high excavations at one setting of the machine. Fig. 2. Kinematics of boom rotatable by 360Fig. 3. 3D virtual model of self-propelled drilling machine.中文部分基于模糊可靠性理论的液压锚杆钻机的电液进料系统的研究摘 要基于模糊数学理论来描述系统的工作条件，与实验相结合，形成了一个采用正态分布隶属函数的计算方法。它更接近实际情况，确保了系统的可靠性。介绍了液压锚杆钻机电液进料系统的建立条件和性能特点，并且联系实际施工中的实验数据，验证了研究方法的可行性。关键词:模糊可靠性；液压锚杆钻机；电液控制系统；正态分布I. 引言 电液系统是工程机械的重要组成部分。目前，电气和液压越来越紧密地结合起来，因此很有必要研究有电气控制部分的集成系统的可靠性1。以保证液压锚杆钻机正常工作的关键因素是较高的电液系统的可靠性。然而，从系统正常运行到出现故障显示了过渡过程中的多种状态。并且，往往很难用准确的数字来描述可靠性的概率。更加科学合理的方法是，应用模糊理论解决完全失效和完全正常之间的模糊可靠性问题2。液压锚杆钻机是岩石锚杆支护中的重要设备。它用于提高大坝地基、打桩地基、挡土墙、挡土墙、边坡治理、深层地基等的横向承载能力（如图1）。由于使用电动液压进料系统时，存在复杂的重负荷、工作时间长、频繁往复运动和恶劣的工作环境等不利的因素，因此失效率较高。图1液压锚杆钻机II.模糊可靠性的计算方法A各组件的模糊可靠性定义 对于系统中的独立分量，可描述为i（I = 1，2,3，N）。固有性能指标为额定压力、电压、流量、电流等，均为离散型随机变量，记作S。系统功能指标包括温度和湿度、压力、电压、系统的流量和电流以及石油清洁度等，均为离散的模糊变量，记作。分量的模糊可靠性计算公式为： (1)式中，-第i分量的第i个固有性能指标值（i= 1,2,3，.，N）-第i分量的第i个功能指标值（i= 1,2,3，.，N）-第n个分量第i个固有的性能指标的概率-第n 个分量第i个功能指标的隶属函数-在阈值中第n个分量第i个功能指标的隶属函数B模糊可靠性的计算模型L. A. Zadeh方法为： (3)式中，不表示分数，而是表示从（总体中的元素）到（隶属函数）的对应关系。 “+”不是和，而是在全域U中的模糊集的符号积分。对串联故障系统，当每个组件的正常工作，该系统才是正常的。否则，它是存在故障的。把U设置为实数域，设置为近似正常的工作系统的模糊可靠性。即：式中，-第i个分量的模糊可靠性-分量的数目一般的计算方法，是将U设为实数域，设为近似工作组件的模糊可靠性。 图2 线性表示即：式中，:模糊数的平均值:置信下限:置信上限它的线性表示含义为：如果关于的函数和关于的函数均是线性的，则等于1；如果变量或者，则等于0；如果，且，则越趋近于，就越趋近于1。应用正态分布的计算方法，使一般的计算方法简易明了3。但是，许多组件的故障概率的样本空间是符合正态分布。这样用正态分布的计算方法精确合理的。把U设置为实数域，设置为近似工作组件的模糊可靠性。则：式中，:模糊数的平均值:置信下限:置信上限图3 正态分布和是通过正态分布的区间估计获得的，其计算公式为：式中，：的无偏估计量、:标准正态分布的百分值：置信度：由不同分量参数获得的值：样本容量如前所述，置信区间是：即：的数量对应的隶属度为1。如果，假设隶属度为0。如果，隶属度为，。为：III.液压锚杆钻机电液进料系统的模糊可靠性计算这项研究的计算以液压锚杆钻机的电液进料系统为例。在液压锚杆钻机的电液系统中，进料系统是工作时间最长的，这对计算来讲是有利因素。图4 液压锚杆钻机结构图图5 进料系统的结构图图6 电液系统逻辑图液压锚杆钻机的电液进料系统由变量泵(I1)、齿轮泵(I2)、油处理(I3)、比例阀(I4)、压力传感器(I5)、控制器(I6)、解开缸(I7)组成，见图5。解开缸驱动动力头瓦解和后援。该系统的建设过程是：第一，解开缸提供动力，以克服负载用于钻井。负载较大，且为几个分量。第二，加管，在管道钻孔到需求深度时，工人需要添加其他管道。由夹具夹紧管道，提供由缸束缚克服的力量，驾驶动力头的起点上，连接管，完成这个过程。第三，给水排渣，排放渣水排放到足够的深度是必要的。碎石和土壤和水一起通过内钻杆来回运动排出。内钻杆由解开缸驱动，解开缸是和动力头联系在一起的。拉出管道，当一个钻孔施工时，这个过程与加入管相反，。但此时有最大的负荷和最高的压力。对于电液进料系统，当每个组件正常工作时，该系统才是正常的。否则，它是存在故障的。所以这是一个由七个部分组成串联故障系统。当系统中的两个部分正常工作，则：当系统中的n个部分正常工作，推导出计算公式：液压锚杆钻机的电液进料系统模糊可靠性的计算方法是：图7车间实验图8施工现场实验随着十个月每天工作8小时的维护和修复记录，每工作周为1个周期，采集压力、温度和其他信号，获得了必要的实验数据。通过应用制造商、参考文件和实验提供的数据，得到了每一个组件的模糊数的平均值。将其代入方程式（6）到（9），计算出值和。见表1：表1将表1中的数据带入到式子（12）得：图9 失效的部件结果显示液压锚杆钻机的电液进料系统正常工作时，模糊可靠性是0.72817，隶属度为1时。该系统的可靠性在0.55024和0.90526之间。换句话说，系统的可靠性值的概率符合正态分布。IV. 结论基于模糊理论和可靠性理论，比较完整地描述了的电液进料系统的可靠性的变化规律。通过跟踪试验，提出了采用正态分布隶属函数计算方法，结果可靠精确。介绍了液压锚杆钻机电液进料系统的建立条件和性能特点，并联系实际施工中的实验数据，验证了研究方法的可行性。另外，结果表明，这种分析方法对研究液压锚杆钻机的电液进料系统的可靠性比较有效，并且为当今越来越普遍的可靠性设计和故障诊断提供了科学的理论依据的。新一代隧道和地下采矿工作自动钻孔机摘 要本文介绍了在设计新一代隧道和地下采矿用自动钻机时的选择问题。要求须建一台机器的这一类分别鉴定和收集。发展（开发）了这些自行研制的钻孔机的原始概念。建立了一个虚拟的模型,并将该模型应用到各种不同数值载荷的情况。提出了负荷轴承结构相结合的有限元强度计算的方法。所有的机器的操作工作已经完全自动化。因而产生了一种新的原创的自动钻孔机。关键词：有限元建模；钻孔机；矿用1介绍钻孔机在隧道和采矿挖掘中得到应用。这类机器必须功能齐全并满足用户的需求。图1显示了一个新的独创的自动化模块钻床。图1 自走式模块化有两个臂钻床。根据该模型,这种自推进采矿机械可用于钻孔或锚索孔。它所有的类型和品种有一个相同的完整的牵引机和一个前面的平台(图1),和不同的工作主要在吊杆和他们的附件。新一代钻孔机的用途是屋顶螺栓或(后重新组合和液压系统修正)隧道和地下矿山钻孔开挖。钻井机器由一个通用牵引机、前面具有一个具有保护操作者的结构的平台，另外给平台还具有一个用于放不同工具的直线吊杆。这台机器能适合扩张和胶粘剂的1.82.6锚长度和直径2838米和钻洞4576毫米直径射击和4340毫米长。另外由于负载敏感液压系统配备有符合人体工学的操纵杆，工作元件可以迅速复位，液压动力机构可以快速调整以适应钻机钻头镗孔或锚索的动力需求。现代静液压传动装置可以调整使机器适应高达12角的地下挖掘，并可确保驱动从内燃机到车轮灵活转移。驾驶室拥有出色的人体工程学操纵条件，并可使所有的噪音和废气减少。由于操作者工作条件非常艰苦，比如高温度（高于35 C）高湿度（约95）的封闭区，空气流动（矿面）有限，机器要配备一个配有空调的人性化的操作室。本机拥有一个可旋转360的直线吊臂（图2），通过一次设置机器，该吊臂的运动可以在35截面上挖掘7.5米宽7.0米高的锚杆支护平行孔。设计这款机器的建议和指导方针是基于市场调查而制定的第一组指导方针包括机器的外型尺寸和参数： 运输高度：最大 2500毫米；一个带空调的可选择驾驶室；锚固挖掘高度：最大 6.5米，钻孔截面积：3035平方米； 驾驶挖掘宽度：最大 4.5米；开挖的纵向坡度：12 ，横坡：7；机器的宽度：最大 2200毫米；机器的速度：一档 高达5公里/小时，二档 高达12公里/小时；与一静液压传动装置，驱动装置可选hydrokinetic标准模型操纵室强度必须满足要求：能量11600J（根据保护操作机构的需要）无论驾驶和工作时，操纵室需要开空调;有效的冷却温度：最小 282K（5），矿山表层外部温度：308345 K，高湿度，当移动到一个新的工作面时温度和湿度频繁变化。图2 吊杆360动力旋转。 图3自走式钻机三维虚22
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