浅谈机械安全-E／E／PE控制系统的功能安全标准IEC62061

循着IEC 62061的架构和脉络,探讨如何从危险风险分析确定SIL、SRECS的安全要求规格书制定、SRECS的设计和集成以及功能安全管理等相关问题.     

LOPA在化工装置SIL定级中的应用

在保证化工生产安全方面,SIL评估是一个很重要的环节。安全完整性等级（SIL）是一个广泛应用的评估安全仪表功能（SIF）的性能指标。保护层分析（LOPA）作为SIL定级中最常用的一种方法,它根据装置生产工艺流程,针对单个风险进行分析,分析风险的保护措施,进行计算,根据结果确定SIL等级。LOPA是一种半定量的评估方法,综合考虑保护层、可接受风险概率和初始事件（IE）概率等多个因素,通过计算量化确定SIL等级。本文简要介绍LOPA评估的基本程序,并以一个简单示例具体说明LOPA的每一个步骤和计算,以供参考。     

第三十七讲:功能安全标准IEC6 1508第二版的变化(一)

本文主要描述了新版IEC61508中一些关于功能安全技术的新变化和新要求,同时介绍了功能安全中心在标准转化过程之中的一些研究心得。由于内容较多,作为一个延续性的讲座,本文是第一篇,主要介绍了在新版标准在失效分类和概率计算方面的变化。     

风险评估在IEC 61010-I标准第三版中的应用

本文介绍ISO/IEC Guide 51中的风险评估方法,然后给出风险评估方法在IEC 61010-1标准第三版中的应用.     

从实例看IEC62061在机械安全领域的具体应用

以某车床车刀电机控制系统为例,通过风险分析、安全计划、安全需求规格书、安全相关控制功能设计与实现等环节简要说明了IEC62061在机械安全领域的应用方法和实现思路。     

风险评估在IEC61010-1标准第三版中的应用

本文介绍ISO／IECGuide51中的风险评估方法，然后给出风险评估方法在IEC61010—1标准第三版中的应用。     

第二十九讲:安全产品SIL认证的鉴别和评估

经过SIL认证或评估的安全产品都具有证明其SIL能力的文档、证书和特殊标示,本文一方面简要介绍了如何鉴别这些资料的规范性、完整性和准确性,另一方面对于其中反映SIL能力的各个参数进行评估,说明其在使用过程中的限制条件和规范准则。     

安全仪表系统安全完整性等级（SIL）评估技术应用

介绍安全仪表系统SIL等级评估过程,并对PTA装置氧化反应器尾氧超8%联锁回路进行评估.通过评估可以合理、有效地设置安全仪表系统,保障石化装置安全完整性.     

功能安全技术讲座第三讲基于风险的SIL确定技术

讲解基于风险的安全完整性等级确定技术,给出三种确定安全完整性等级的方法。     

乙烯装置安全仪表系统SIL评估要点分析

以乙烯装置为分析对象,重点介绍了SIL评估方法,即LOPA分析法和可靠性框图法.基于这两种方法进行全面的SIL评估,发现并分析该装置安全仪表系统可靠性不足之处,提出合理可行的优化方案,进一步提升装置运行的安全可靠性.     

过程工业部门仪表型安全系统的功能安全

概述制定国际标准IEC61511“过程工业部门仪表型安全系统的功能安全”的意义、范围和组成。介绍了IEC61511同国际标准IEC61508“电气/电子/可编程电子安全相关系统的功能安全”的关系。分别说明了IEC61511的3个部分的范围和主要内容。并说明基于IEC61511的过程仪表安全技术有着广泛的应用前景。     

功能安全评估技术及工具化解决方案

结合基于风险的SIL确定、PFD计算、SIL确认和优化等功能安全先进技术的讨论,介绍一款功能安全专用工具。该工具充分体现了“全系统、全生命周期”的功能安全设计理念,是SIL评估和优化设计的必备工具之一。     

Robust state estimation based on sliding mode observer for aeroelastic system

This paper concerns the application and demonstration of sliding mode observer for aeroelastic system, which is robust to model uncertainty including mass and stiffness of the system and various disturbances The performance of a sliding mode observer is compared with that of a conventional Kalman filter to demonstrate robustness and disturbance decoupling characteristics. Aeroelastic instability may occur when an elastic structure is moving even in subcritical flow speed region Simulation results using sliding mode observer are presented to control aeroelastic response of flapped wing system due to various external excitations as well as model uncertainty and sinusoidal disturbances in subcritical incompressible flow     

What does mean mean? – A systematic treatment of statistical methods for measurand estimation

Results of a study in statistical methods for point-wise estimation are presented. Estimation criteria based on unbiasedness, minimum-mean-square-error, maximum likelihood, least squares, and on decision theory are compared and contrasted. Decision theory emerges as a parsimonious and powerful rational, able to unify both ‘frequentist’ and ‘Bayesian’ estimation principles, and to reduce inflation of ad hoc solutions.     

Force estimation and failure detection based on disturbance observer for an ear surgical device

The disturbance observer is one of the useful tools for estimating the contact force between the subject body and the environment in robotic and mechatronic systems. This paper introduced a novel automatic office-based ear surgical device for the treatment of Otitis Media with Effusion (OME) under the guidance of force sensing information. Since the force sensing information must be reliable so as to ensure the safety of the device, a contact force estimation method based on the disturbance observer is proposed. The system model is built and a control strategy is proposed and developed. In the control strategy, a composite motion controller for an ultrasonic motor (USM) stage is presented, and then the design and the stability analysis of an advanced disturbance observer is given. Furthermore, a contact estimator and a failure detector, aiming to enhance the safety and reliability enhancement, are designed. Finally, the proposed control strategy is studied with both simulation and experiment. The experimental results show that the advanced disturbance observer can estimate the actual contact force correctly and precisely, and the disturbance observer based force estimation and failure detection method is feasible which can be used in force sensing, contact detection and fault diagnosis.     

Kinematic calibration of gantry hybrid machine tool based on estimation error and local measurement information

This paper presents the kinematic calibration of a four degrees-of-freedom (DOF) hybrid machine tool based on a novel planar 3-DOFs parallel mechanism and a long movement of the worktable. Closed-form solutions are developed for both the inverse and direct kinematics about the parallel mechanism. The error model is built and the mechanism accuracy is investigated. Two types of kinematic calibration method are proposed by a simple measurement device. The first type of calibration method is based on estimation error, and can easy improve the machine tool accuracy quickly by estimating the error trends. The second type of kinematic calibration method is based on local measurement information, which includes the position errors and does not include the pose errors of the machine tool. The calibration tests showed the effectiveness of the calibration methods, which can be useful for the similar types of parallel machine tool.     

Sonar based position estimation system for an autonomous mobile robot operating in an unknown environment

The paper presents a new method of position estimation for robot navigation in a completely unknown environment. The method is different from conventional ones in that it does not need any kind of a priori reference model or man-made landmarks. A series of local maps is built and updated from sonar data while the robot is exploring the unknown environment. Among the constructed local maps, the robot autonomously selects the ones with distinctive features and memorizes them as reference landmarks. An orientation clustering method is developed which enables the robot to extract the features of the map. The maps selected in such a way are then used to estimate the position and orientation of the robot while undertaking the given task. In doing so correspondence indices are defined to determine the corresponding reference map to the current local one among the numerous stored maps. The two maps are matched so as to minimize the discrepancy between them, thus enabling one to estimate the position and orientation of the robot. The usefulness of all these approaches is illustrated with the results produced by a real robot equipped with ultrasonic sensors.     

机电产品设计过程中的成本估算与控制方法研究

采用基于模糊理论的加权相似方法估算零部件的成本,同时利用占比计算系统得到零部件的目标成本,通过计算改进率确定修改优先级,以此达到控制产品成本的目的.以CNC机床的传动系统开发为例论述了方法的应用,结果表明,提供的方法可以很好地控制产品的寿命周期成本.     

Energy based signal parameter estimation method and a comparative study of different frequency estimators

The influences of window functions and noise on the performance of the energy-based signal parameter estimation method are investigated, and the appropriate parameters and algorithm are recommended accordingly. The frequency, amplitude and phase estimation variances of the energy based method are deduced and verified by computer simulation. The performances of four frequency estimation methods are compared: the energy based method, the interpolation based method, the phase difference based method and the Fourier transform (FT) continuous zoom based method. For the second and third methods, the Quinn algorithm and the phase difference based method with factor η=0.5 are recommended, respectively. It was found that each method has its own advantages. The energy based method has the best stability compared with others. The interpolated method has the lowest frequency estimation variance when the frequency biasδ is large, while the phase-difference based method does better when δ is low. The change of δ does not influence the maximum frequency estimation error of the FT continuous zoom based method. Comparatively speaking, the phase-difference based method has the least frequency estimation error.     

用IEC61508标准分析福岛核灾难源头与失策及其Profi—Hierarcky解决方案

分析2011年日本东北近海地震一海啸致福岛核电灾难，发现有严重不符IEC61508风险-SIL准则的多处“冒险点”。结论：决策失误来自忽视基础技术的部门垄断。