Distributed system design based on dependability evaluation: a case study on a pilot thermal process

The aim of this paper is to test and validate a methodology for the design of distributed systems by evaluating performances and dependability (more specially reliability and availability). The optimal material architecture of the automation system is determined from an over-dimensioned preliminary material architecture, and from the functional decomposition of this system. The interest of this method is to allow an early comparison of several choices of architecture, and of sets of components, during the designing of the system. One of the results of our work is described below as the application of the method for the designing of a pilot thermal process.     

On the considerations for the design of an automated aircraft sheet metal component production loft generation system

In this paper an ambitious production loft generation system (PLGS) is created to incorporate innovative and unique features of aircraft sheet metal component (SMC) lofts meeting the stringent standards of aircraft industry owing to non-availability of suitable public domain software. This system is fully tested and validated with the support of the aircraft industry. It provides for automated blank layout generation based on surface models utilizing some unique algorithms and vector logics created through research and development over a period of 15 years taking into account the material properties, flow direction and plasticity and strives to eliminate post forming trimming operations by utilizing the databases of the aircraft industry. For the first time such a custom built system is created, which incorporates industrial process data and provides a host of processing options, together with various design cum production features like mould lines, joggles, bend relief, tooling holes, pilot holes, cut outs, chamfers/fillets, inspection angles etc. and displays features needed for quality assurance as essential ingredients. It has inbuilt, intelligent, high efficiency processing features such as the utilization of symmetry facilitating fractional processing of the SMC. This paper includes a brief account of various issues related to the chronology of design of the systems, implementation of the design options, intricacies of methods deployed, their efficacy and combinatorial suitability. Crucial ground breaking new algorithms relevant to the production features are also elucidated in this paper.     

Training of the maintenance personnel to prevent failures in aircraft systems

The aircraft maintenance process plays a vital role in aviation safety. The quality of the maintenance process and the qualifications of the aircraft maintenance personnel are important factors in the safety of aircraft.In this study the aircraft maintenance training model has been developed by especially taking in to account the EASA Part 66 regulations. The progression of the aircraft maintenance personnel training was investigated and suggestions to improve training process were given so as to prevent failures in aircraft systems.     

The NRC Bell 412 ASRA safety system: a human factors perspective on lessons learned from an airborne incident

The National Research Council (NRC) Bell 205 Airborne Simulator is a full authority fly-by-wire (FBW) research helicopter. On 24 May, 1996 this aircraft underwent a failure which drove all four flight control actuators to full extension shortly after engagement of the FBW system, with nearly catastrophic results. The sound design inherent in the original Bell 205 safety system allowed the safety pilot to override the FBW system and prevented the loss of aircraft and crew. This incident, however, led to the realization that the existing safety system configuration in the Bell 205 was only marginally acceptable, and that this same system would be inadequate for the next generation FBW aircraft, the NRC Bell 412 Advanced Systems Research Aircraft (ASRA). Experience gained from the Bell 205 incident, and historical experience, has driven the design process of the safety systems for ASRA, with a particular view toward the capabilities and limitations of the operators.     

Making IT fit: the design of integrated manufacturing systems

One of the important implications of information technology (IT) is that it has made possible widespread automation in manufacturing industry. However, the bulk of this has involved discrete automation of single plant items or process elements rather than the total production system. Although the capital cost of such total system automation is a significant factor in slowing the rate of change in this direction, there are also a number of problem issues related to the integration of machines, computers and human systems within manufacture and design. Arguably the types of issue involved are not fully understood and in many cases the technological change is demanding totally new approaches and responses to the design of production systems and the traditional manufacture/design connections.The paper explores some of the issues raised in advanced manufacturing systems, drawing on case study research into the adoption of flexible manufacturing systems as an example of computer-integrated manufacture. It comments on the experience of case study firms and presents some comments on the design problems facing those responsible for integrated manufacturing systems.     

Cable failure resulted in the crash of a trainer aircraft

A training aircraft was crashed during a training session. The pilot and the trainer ejected out before the crash. The aircraft was elucidating the spin and recovery motion in the air. During a spin motion the aircraft did not recover and crashed to the ground. Rudder and elevator cables were found failed in initial investigation. They were seemed to be failed before crash. The failed cables retrieved from the crashed aircraft as well as un-failed used cables from the in-service aircrafts were subjected to further analysis. The results revealed that more than 50% wires of a rudder cable was failed under the fatigue mechanism and fractured catastrophically rendering the rudder out of order. The material of this particular cable was also different from the other un-failed/failed cables having comparatively lower mechanical strength. The pilots applied the rudder controls for recovery from spin motion, but could not find it operational. The aircraft crashed due to failure of rudder cable. The failure of other cables was the after effects of the impact of aircraft to the ground.     

民机进近着陆飞行操纵人机交互适航场景捕获模型构建

目的 构建面向民机进近着陆任务的飞行操纵人机交互场景捕获模型,为进近着陆安全分析和民机正向设计提供参考。方法 厘清场景捕获的基本内涵及层次任务,通过民机进近着陆操纵场景任务划分、场景维度设计、场景节点确定以及场景内容描述,建立人机交互场景捕获模型与实施程序。通过民机进近着陆中的下降、着陆等典型子任务场景,对民机进近着陆飞行操纵人机交互场景捕获实例进行验证与应用。结果 成功构建了飞行操纵人机交互场景模型。结论 针对民机进近着陆任务,构建了飞行操纵人机交互场景捕获模型,建立了飞行操纵场景任务及实施步骤,给出了飞行操纵场景节点与场景内容描述,为民机进近着陆系统安全性分析及基于正向的民机设计制造提供了理论依据。     

Design and operation of single-loop dual-rail inter-bay material handling system

Asynchronized automated material handling systems, e.g. automated electrified monorail systems and automated guided vehicle systems, have been playing important roles in manufacturing. Reliability becomes a critical issue as manufacturing enterprises are moving toward automation. In the past, reliability tissue has not been analysed explicitly for these types of systems. In this research, a new measure was proposed to specify reliability. A mixed integer programming model was developed to design flow paths for a special class of material handling systems, i.e. single-loop dual-rail systems. The model can be used to design systems with higher reliability. The model and application procedure in design and analysis were demonstrated through two case studies.     

Training programme on engineering applications at the CityPolytechnic of Hong Kong

An integrated training programme on engineering applications has been devised to meet the unique socio-economic needs of Hong Kong. The programme is directed at the design of a product which is competitive in the world market because product design is of paramount importance to the local export-oriented electronics industry. It comprises modules taught during the regular academic year and practical sessions held in a simulated industrial environment in the summer. Students are involved in nearly all aspects of the production process. It is an integrated programme because material covered in taught modules and the practical training are blended together to form a consolidated programme with a common theme. The programme has been operational for six years; feedback from former students their employers, industrialists, and members of accreditation teams is, in general, favourable     

飞机撞击特大型LNG储罐全过程仿真分析

采用数值模拟方法对飞机撞击特大型LNG储罐的全过程进行仿真分析。分析中采用LS-DYNA有限元程序,考虑罐体、储液与保温层间的相互问题,建立了F-15战斗机的SPH模型,对飞机材料的选择和参数确定进行了详细分析,并以Riera法为依据,对F-15战斗机SPH模型撞击刚体所产生的荷载进行了对比验证,对比结果证明了SPH模型的可靠性和实用性。分析结果表明：撞击角度越大,外罐所承受的撞击能量越大,相应的内罐破坏越小,因此垂直撞击为最不利撞击角度;撞击高度对整体工况计算结果影响不大,储罐在经受215m/s撞击速度撞击下均出现了严重破坏;112m/s撞击速度时内罐尚有安全余量,160m/s撞击速度时内罐撞击中心区域内材料已达到极限应变,因此可认为目前设计方法设计的储罐所能承受的最大撞击速度为160m/s。     

Tablet Press Automation: A Modular Approach to Fully Integrated Production

Fully automated tablet production is an exciting and emerging trend in the pharmaceutical industry. Improved tablet quality, manufacturing efficiency, and process validation are major reasons for the increasing emphasis on automated technology. This paper outlines the vast options and possibilities associated with tablet press automation and presents a specific modular approach in which the extent and time flame for the automation transition is dictated by the tablet manufacturer. This modular approach uses the tablet press control system as the central building block on which a variety of control modules are constructed to facilitate automated material flow, data collection, and remote process monitoring. The emphasis is placed on design flexibility due to the fact that each company will construct a unique definition of automation, which may be subject to change as various phases of automation are implemented and evaluated.     

Progress in experimental stress analysis for Airbus aircraft design

Advanced experimental stress analysis techniques have been increasingly used on large aircraft structures to provide stress data for both design and numerical analyses validation. In the past these techniques tended to be limited to the structural test phase which is subsequent to the design and manufacture stage. Experimental stress techniques have had to become more sophisticated and utilised much earlier in the programme in order to meet the ever increasing demands for competitive, aircraft design, performance and reliability. Currently the techniques have applications from the earliest design stage through to final in-service support engineering. Photoelastic stress analysis was one of the earliest and most powerful experimental design tools in use at Filton, however, the range of techniques is continually being extended to meet the technological demands of new designs. This has involved keeping abreast of a wide array of sciences to identify and develop new physical procedures for stress related experimental analysis. Progress is reviewed in this paper as well as the vision for the future within the context of Airbus aircraft design. The economic and technical pressures to move towards more automation and image processing are discussed including the requirement to provide data that is more user friendly to conventionally trained design and stress engineers.     

Applied Integrated Design in Composite UAV Development

This paper presents a modern approach to integrated development of Unmanned Aerial Vehicle made of laminated composite materials from conceptual design, through detail design, strength and stiffness analyses, definition and management of design and production data, detailed tests results and other activities related to development of laminated composite structures with main of its particularities in comparison to metal structures. Special attention in this work is focused to management processes of product data during life cycle of an UAV and experimental tests of its composite wing. Experience shows that the automation management processes of product data during life cycle, as well as processes of manufacturing, are inevitable if a company wants to get cheaper and quality composite aircraft structures. One of the most effective ways of successful management of product data today is Product Life cycle Management (PLM). In terms of the PLM, a spectrum of special measures and provisions has to be implemented when defining fiber-reinforced composite material structures in comparison to designing with metals which is elaborated in the paper.     

The use of Functional Resonance Analysis Method (FRAM) in a mid-air collision to understand some characteristics of the air traffic management system resilience

The Functional Resonance Analysis Model (FRAM) defines a systemic framework to model complex systems for accident analysis purposes. We use FRAM in the mid-air collision between flight GLO1907, a commercial aircraft Boeing 737-800, and flight N600XL, an executive jet EMBRAER E-145, to investigate key resilience characteristics of the Air Traffic Management System (ATM). This ATM system related accident occurred at 16:56 Brazilian time on September 29, 2006 in the Amazonian sky. FRAM analysis of flight monitoring functions showed system constraints (equipment, training, time, and supervision) that produce variability in system behavior, creating demand resources mismatches in an attempt to perceive and control the developing situation. This variability also included control and coordination breakdowns and automation surprises (TCAS functioning). The analysis showed that under normal variability conditions (without catastrophic failures) the ATM system (pilots, controllers, supervisors, and equipment) was not able to close the control loops of the flight monitoring functions using feedback or feedforward strategies to achieve an adequate control of an aircraft flying in the controlled air space. Our findings shed some light on the resilience of Brazilian ATM system operation and indicated that there is a need of a deeper understanding on how the system is actually functioning.     

极寒条件下航空机务服数字化设计应用研究

目的 研究服装数字化技术在航空机务服设计中的应用。方法 运用文献研究法、案例分析法及实验法,对航空机务服数字化设计应用研究的相关情况进行概述,研究服装数字化技术在航空机务服设计中应用的可行性及其优势。结果 以航空机务服设计过程为例,证实服装数字化技术适用于工作服的定制化设计生产,将在研究航空机务服设计各环节的基础上,进行设计模块的数字化技术研究。结论 随着人们对服装设计生产制造过程的数字化、自动化、智能化的需求不断增长,服装二维及三维的相关数字化技术也渐趋成熟。服装数字化技术在工作服定制化服务中具有良好的发展前景,通过服装数字化技术设计的极寒条件下的工作服能够满足航空机务员的需求,保障了航空机务员户外工作的顺利开展,进而维护了航空的飞行安全。     

ARALL (Aramidfaserverstärkter Aluminiumschicht-Verbundwerkstoff) - Ein neuer Hybrid-Verbundwerkstoff mit besonderen Schwingfestigkeitseigenschaften

ARALL (Aramid Fibre Reinforced Aluminum Laminate)-A New Fatigue Resistant Hybrid Composite High fuel expenses and the tendency to build larger aircrafts are two main factors forcing the aircraft engineers to develop structures which allow for higher design stress levels. Higher design stress levels require an increasing concern with the fatigue behavior of the structure. One way to solve the problem is to develop new high strength fatigue resistant materials. In this paper a material of this type is presented: ARALL, an aramid fibre reinforced aluminum laminate. This hybrid material consists of thin sheets of a high strength aluminum alloy which are bonded together. Into the bond-line thin layers of aramid fibres are embedded. As soon as fatigue cracks are initiated in the metallic part of the hybrid composite material during the fatigue loading, the strong and fatigue insensitive aramid fibres remain unbroken behind the propagating crack. They hinder the crack opening and reduce the stress intensity factor at the crack tip in the metal part of the hybrid composite. This mechanism leads to a significant reduction of the crack growth and can be enhanced by introducing favourable residual stresses into the hyb- rid material. For an optimized ARALL material an aluminum sheet thickness of about 0.5 mm and an aramid layer thickness of about 0.25 mm (with a fibre volume content of about 40–50%) are chosen. ARALL decreases the crack growth rates by orders of magnitude, as compared to monolithic aluminum sheets, and is an extremely damage tolerant material.     

ARALL: A materials challenge for the next generation of aircraft

The development of new aircraft is significantly influenced by the introduction of new structural materials. A driving force behind such developments is the perpetual incentive of reducing the aircraft operating costs of which the most important aspects are fule consumption and maintenance.

The structural weight of the aircraft has a high impact on the fuel consumption. Reduction of the weight can be achieved by the introduction of advanced structural design techniques together with new materials which have low density and high (static and dynamic) stress level capabilities. Maintenance costs can be reduced mainly by enlarging the inspection periods of the aircraft. These two aspects, together with the new damage tolerance requirements (FAR and JAR) and durability questions in view of increasing aircraft lives, make the design of an aircraft with low operating costs very complex and difficult.

In this whole process the selection of materials becomes a critical issue. This is illustrated by considering three potential families of materials:

1. - aluminium alloys (both new and conventional)

2. - composites

3. - aramid aluminium laminate (ARALL).

Special attention is given to the development and possible applications of the ARALL material.     

Feature-driven,process-based approach to the integration of CAD /CAM in wireframe models

This paper presents a structure for an integrated CAD/CAM system in wireframe models than can be simultaneously used for product design and manufacture of prismatic components. A feature-driven, process-based design methodology, which derives its basis from traditional geometry-based design, feature-based design, deterministic and expert heuristic manufacturing knowledge, is proposed. This methodology provides an integrated modelling environment for automation of downstream manufacturing applications such as process planning and NC code generation. Representation of features in the design database is not limited to geometry alone but includes material, tooling and machine specifications and is based on a process-to-geometry mapping. Research shows that informational completeness of a CAD database depends on application; and for manufacturing tasks, the vocabulary of the process describing the means of making a part should be mapped directly to the feature-based geometry. This effort answers key issues in integrating CAD and CAM in the most widely used wireframe modelling systems.     

Similarities and differences between human–human and human–automation trust: an integrative review

The trust placed in diagnostic aids by the human operator is a critical psychological factor that influences operator reliance on automation. Studies examining the nature of human interaction with automation have revealed that users have a propensity to apply norms of human–human inter-personal interaction to their interaction with ‘intelligent machines’. Nevertheless, there exist subtle differences in the manner in which humans perceive and react to automated aids compared to human team-mates. In the present paper, the concept of trust in human–automation dyads is compared and contrasted with that of human–human dyads. A theoretical framework that synthesizes and describes the process of trust development in humans vs automated aids is proposed and implications for the design of decision aids are provided. Potential implications of this research include the improved design of decision support systems by incorporating features into automated aids that elicit operator responses mirroring responses in human–human inter-personal interaction. Such interventions will likely facilitate better quantification and prediction of human responses to automation, while improving the quality of human interaction with non-human team-mates.     

Framework on robotic percussive riveting for aircraft assembly automation

Presented in this paper is a framework for the implementation of a robotic percussive riveting system, a new robot application for aircraft assembly. It is shown here that a successful robot application to the automation of a process requires in-depth research of the process and the interaction with the robot. For this purpose, a process planning-driven approach is proposed to guide a robot application research.Atypical process planning will involve a list of
key considerations including: process sequence, process parameters, process tooling, and process control. Through this list, a number of key research issues are identified for robotic percussive riveting, such as rivet pattern planning,rivet time determination, rivet tooling design and rivet insertion control. The detailed research on these issues has effectively created know-how for the successful implementation of our robotic percussive riveting system.