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Viewing 151 to 180 of 4781
2014-04-01
Technical Paper
2014-01-0747
Youji Hiraoka, Katsunari Yamamoto, Tamotsu Murakami, Yoshiyuki Furukawa, Hiroyuki Sawada
Abstract The authors propose computerized support for Fault Tree Analysis (FTA) based on new knowledge management in product design. FTA is a method of analyzing and visualizing the causes of a fault event by Fault Tree diagram (FT diagram) that has a tree structure with logical step. Many methods of support for FTA are studied, but they are not effective for our FTA. We have developed the system of Computer-Aided FTA (FTAid) for design engineers by the collaborative research group (JATCO Ltd, The University of Tokyo and National Institute of Advanced Industrial Science and Technology). We reported this system in SAE2012 World Congress. After that, the knowledge management for FTA and new functions of this system have been studied continuously. In this paper we report that FT diagrams used FTAid improved to be useful for design engineers are analyzed based on individual qualification and skill of FTA, we study improvement of FTAid and the FTA education system.
2014-04-01
Technical Paper
2014-01-0724
Derek R. Braden, David M. Harvey
Abstract There is a continual growth of test and validation in high reliability product applications such as automotive, military and avionics. Principally this is driven by the increased use and complexity of electronic systems deployed in vehicles, in addition to end user reliability expectations. Higher reliability expectations consequently driving increased test durations. Furthermore product development cycles continue to reduce, resulting in less available time to perform accelerated life tests. The challenge for automotive electronic suppliers is performing life tests in a shorter period of time whilst reducing the overall associated costs of validation testing. In this paper, the application of prognostic and health monitoring techniques are examined and a novel approach to the validation and testing of automotive electronics proposed which it is suggested may be more cost effective and efficient than traditional testing.
2014-04-01
Technical Paper
2014-01-0281
Peter Subke
Abstract In the past, the automotive industry has learned the lesson that competition on the level of bits and bytes, proprietary bus systems, data communication and diagnostic protocols is unrewarding. Too much time and money has been spent on the development of proprietary diagnostic tools. Vehicle manufacturers and suppliers realized that standardization would be the best way to overcome this situation. Furthermore, regulatory requirements in the US and the EU for such standardization have strengthened this lesson. As a result, the automotive industry has standardized the technology for the communication of external test equipment with electronic control units (ECUs) in road vehicles. Standardization serves the price, the quality and the maintainability via scale and training curve effects.
2014-04-01
Journal Article
2014-01-0279
Rasoul Salehi, Aria Alasty, Gholam-Reza Vossoughi
Proper operation of an internal combustion engine is required by demands of a vehicle driver and governmental legislations. Therefore it is necessary to monitor, within an online technique, the engine and detect any fault which disrupts its normal operation. In this paper, the air-charge path, as a key element in a turbocharged engine, is monitored for an air leakage fault. At first, a robust algorithm to estimate unmeasured turbocharger rotational speed is presented. The sliding mode methodology is used to design the estimator which is shown to be robust to the compressor modeling uncertainties. The estimation error from the sliding mode observer (SMO) is then used to detect abnormal behavior of the turbocharger along with the engine due to a leakage fault in the air-charge path. Experimental results from a modern turbocharged SI engine indicate the designed monitoring technique is able to detect a leakage fault, of 7 mm or higher sizes, in the air-charge path.
2014-04-01
Journal Article
2014-01-0280
Rui Chen, Xinlei Wang
Abstract In this paper, a model-based diagnostic system was developed to detect and isolate the dosing fault and the outlet NOx sensor fault for the SCR system. The dosing fault is treated as an actuator additive fault, while the outlet NOx sensor drift and/or offset fault is treated as a sensor additive fault. First, a 0-D SCR model was developed to facilitate the model-based approach. A parity equation residual generator was designed based on the linearized SCR model and the fault transfer function matrix. The diagnostic algorithm is then implemented in the Matlab/Simulink environment for validation. A high fidelity nonlinear 1-D SCR model is used to generate system outputs and to simulate the plant. The simulation results show that the model-based fault diagnosis system succeeds in detecting and isolating the outlet NOx sensor and dosing faults with good sensitivity and robustness
2014-04-01
Journal Article
2014-01-0282
Alex Beresnev, Max Beresnev
The article provides the rationale for, and describes a new internal combustion engine (ICE) diagnosing method, which involves obtaining a signal within the audio frequency range and its examination together with engine performance through the use of algorithms of high resolution time-and-frequency analysis and techniques involving partial signal reconstruction in the phase space. Examples of how the method may be applied to reveal defects and faults of various units and systems are also described in the article. The paper shows that the method may also be used for other assemblies and units of cars (apart from engines) to analyze patterns for periodic wave structures.
2014-04-01
Journal Article
2014-01-1448
Johan Hult, Simon Matlok, Stefan Mayer
A combination of optical and laser based methods have been employed for simultaneously studying fuel jet penetration and ignition behaviour of fuel jets inside the cylinder of a large marine two-stroke diesel engine during operation. Tests were performed on a four-cylinder Diesel engine with a bore diameter of 0.5 meter. Optical access was obtained through a custom designed engine cover. A double pulsed laser was employed for global illumination of the liquid fuel jet. For detection a dual camera set-up was employed, which allowed both simultaneous fuel jet and flame emission imaging, or dual frame fuel jet imaging for velocity measurements. From the data recorded the liquid penetration, jet cone angle, jet penetration velocity, ignition location, ignition time and flame lift-off could be extracted. Data was recorded for two different charge densities and temperatures, for two different atomizer designs, and for two different fuels.
2014-04-01
Journal Article
2014-01-0284
Håkan Warnquist, Mattias Nyberg, Jonas Biteus
When a truck or bus suffers from a breakdown it is important that the vehicle comes back on the road as soon as possible. In this paper we present a prototype diagnostic decision support system capable of automatically identifying possible causes of a failure and propose recommended actions on how to get the vehicle back on the road as cost efficiently as possible. This troubleshooting system is novel in the way it integrates the remote diagnosis with the workshop diagnosis when providing recommendations. To achieve this integration, a novel planning algorithm has been developed that enables the troubleshooting system to guide the different users (driver, help-desk operator, and mechanic) through the entire troubleshooting process. In this paper we formulate the problem of integrated remote and workshop troubleshooting and present a working prototype that has been implemented to demonstrate all parts of the troubleshooting system.
2014-04-01
Journal Article
2014-01-1260
Cosmin Emil Dumitrescu, Christopher Polonowski, Brian T. Fisher, A. S. (Ed) Cheng, Gregory K. Lilik, Charles J. Mueller
Natural luminosity (NL) and chemiluminescence (CL) imaging diagnostics are employed to investigate fuel-property effects on mixing-controlled combustion, using select research fuels-a #2 ultra-low sulfur emissions-certification diesel fuel (CF) and four of the Fuels for Advanced Combustion Engines (FACE) diesel fuels (F1, F2, F6, and F8)-that varied in cetane number (CN), distillation characteristics, and aromatic content. The experiments were performed in a single-cylinder heavy-duty optical compression-ignition (CI) engine at two injection pressures, three dilution levels, and constant start-of-combustion timing. If the experimental results are analyzed only in the context of the FACE fuel design parameters, CN had the largest effect on emissions and efficiency.
2013-11-27
Technical Paper
2013-01-2883
Rajesha Kundrukote
A vehicle electronic control unit consists of various high side power stages for driving different loads. Common faults such power stages experience are Short Circuit to Battery (SCB), Short Circuit to Ground (SCG) and Open Load (OL). These faults can occur during either on-state or off-state of power stage output. It is essential to diagnose a fault such as SCB during switch off-state, SCG during switch on-state and OL during both on and off-state of the switch in order to avoid system malfunction, power-stage damage etc. A high-side power-stage mainly consists of a switching power MOSFET and its driver section. Quite often the semiconductor manufacturers provide diagnostic information through a digital status (ST) output. A logic low level on the ST pin indicates a fault. The limitation the ST signal is its inability to distinguish faults SCG, SCB and OL. For high-side switches (HSS), to overcome these drawbacks, there is a need of proper diagnosing technique.
2013-10-14
Journal Article
2013-01-2544
Chao Liu, Changfu Zong, Lei He, Chunshan Li, Minghui Liu
A fault detection and diagnosis (FDD) algorithm of 4WID/4WIS Electric Vehicles has been proposed in this study aiming to find the actuator faults. The 4WID/4WIS EV is one of the promising architectures for electric vehicle designs which is driven independently by four in-wheel motors and steered independently by four steering motors. The 4WID/4WIS EVs have many potential abilities in advanced vehicle control technologies, but diagnosis and accommodation of the actuator faults becomes a significant issue. The proposed FDD approach is an important part of the active fault tolerant control (AFTC) algorithm. The main objective of the FDD approach is to monitor vehicle states, find the faulty driving motor and then feedback fault information to the controller which would adopt appropriate control laws to accommodate the post-fault vehicle control system.
2013-10-07
Technical Paper
2013-36-0228
Fernanda Meneses Kelly, Helaine Maria Braga Sbampato
On cab-over trucks to access the engine and others components it is necessary to tilt the cab. This is a regular procedure done several times during the vehicle life cycle. In order to make it easier and safer for mechanical tilting system, it was developed an articulated safety bar to sustain and maintain the cab on the open position. On the current bars available in the market, to close the cab it is necessary that the operator get under the cab to disengage the safety bar. This procedure puts the operator under risk because an accident can happen while the disengagement and the cab can close over him. Thinking on that and looking for a better ergonomic and safety situation, the objective of this work is to present a new articulated safety bar that the engagement and disengagement is done automatically with the natural tilting movement of the cab. This solution was developed at Iveco Latin America for adoption on the new Vertis HD and is under patent process.
2013-10-07
Technical Paper
2013-36-0248
Hélio Rocha Pegorer, João Vilan Júnior, Max Mauro Dias Santos
The increasing application of embedded electronic components in vehicles brings the need to use diagnostic systems for track and control of parameters. Development, manufacturing and after-sales are all fields that use diagnostic systems' help to execute their tasks. Applying communication protocols such as KWP2000, SAEJ1939/73 and UDS makes diagnostic device and automotive network communicate to each other according to standards. This work aims to present an overview about a few communication protocols for diagnostic and services, by showing their specific tools and applications.
2013-09-24
Journal Article
2013-01-2408
Arnold Taube, Michael Mercier
Adoption of a new Electronic Systems Computer-Aided Design (ECAD) system for modeling electrical systems design by Product Engineering offers the promise of improved accuracy and productivity for Service Publication's authors to create wiring diagrams and to standardize their format; while improving the comprehension and functionality of those documents for service technicians. It is also potentially disruptive, requiring new workflows, processes, standards and lines of communication to be developed. This paper describes how to structure and organize a project for effectively and efficiently bringing a new ECAD system for modeling electrical system design into Service Publications. It also provides insight into some lessons learned.
2013-09-24
Journal Article
2013-01-2409
Tomi Krogerus, Mika Hyvönen, Kalevi Huhtala
In this paper, the operating states of a wheel loader were studied for diagnostics purposes using a real time simulation model of an articulated-frame-steered wheel loader. Test drives were carried out to obtain measurement data, which were then analyzed. The measured time series data were analyzed to find the sequences of operating states using two different data sets, namely the variables of hydrostatic transmission and working hydraulics. A time series is defined as a collection of observations made sequentially in time. In our proposed method, the time series data were first segmented to find operating states. One or more segments build up an operating state. A state is defined as a combination of the patterns of the selected variables. The segments were then clustered and classified. The operating states were further analyzed using the quantization error method to detect anomalies.
2013-09-20
Journal Article
2013-01-9041
Shawki Abouel-Seoud, Mohamed Khalil, Sameh Metwalley, Essam Allam, Hany Assad
Reliability has always been an important aspect in the assessment of industrial products and/or equipments. Good product design is of course essential for products with high reliability. However, no matter how good the product design is, products deteriorate over time since they are operating under certain stress or load in the real environment, often involving randomness. Maintenance has, thus, been introduced as an efficient way to assure a satisfactory level of reliability during the useful life of a physical asset. The earliest maintenance technique is basically breakdown maintenance (also called unplanned maintenance, or run-to-failure maintenance), which takes place only at breakdowns. A later maintenance technique is time-based preventive maintenance (also called planned maintenance), which sets a periodic interval to perform preventive maintenance regardless of the health status of a physical asset. The vehicle component is judged to be safe depending on its reliability.
2013-09-17
Technical Paper
2013-01-2315
Raphael Van Der Vorst, Jean Louis Magerman, Bruno Bernay, Swen Vandenberk, Alex Carrella
Wing Anti-Icing Systems (WAIS) are integral part of a wing design. Their presence ensures safety in all-weather conditions. In standard designs, the WAIS are fitted in the slat internal structure and runs throughout its span in between the ribs. Given its critical function, such a system has to pass qualification test. The test specification is dictated by international standards. In the case discussed in this article, the standard adopted is the RTCA DO-160G “Environmental Conditions and Test Procedures for Airborne Equipment”. In particular, the work presented here concerns with the Vibration environmental test. The standard prescribes a number of dynamic tests to be carried out on the AIS: random, shock and sine excitation tests have to be performed in order to study their effect on the parts composing the Anti-Icing System. The standard prescribes vibration levels at the attachment locations of the AIS to the wings' ribs.
2013-09-17
Technical Paper
2013-01-2294
Faisal Khan, Ian Jennions, Tarapong Sreenuch
In today's aircraft the diagnostic and prognostic systems play a crucial part in aircraft safety while reducing the operating and maintenance costs. Aircraft are very complex in their design and require consistent monitoring of systems to establish the overall vehicle health status. Most diagnostic systems utilize advanced algorithms (e.g. Bayesian belief networks or neural networks) which usually operate at system or sub-system level. The sub-system reasoners collect the input from components and sensors to process the data and provide the diagnostic/detection results to the flight advisory unit. Several sources of information must be taken into account when assessing the vehicle health, to accurately identify the health state in real time. These sources of information are independent system-level diagnostics that do not exchange any information/data with the surrounding systems.
2013-09-17
Technical Paper
2013-01-2227
Shuhei Segawa, Junich Tamura, Satoshi Suzuki, Hisao Oka, Kiichi Meguro, Yoshiji Satou
In the expansion of composite material application, it is one of the most important subjects in assembly of aircraft structure how drilling of composite/metal stack should be processed in an efficient way. This paper will show the result of development of a drill bit for CFRP/Aluminum-alloy stack by Kawasaki Heavy Industries (KHI) and Sumitomo Electric Hardmetal (SEH). In order to improve workability and economic performance, the drill bit which enables drilling CFRP/Al-alloy stack: at 1 shot; from both directions; without air blow and coolant (just usual vacuuming); was required. A best mix drill bit which has smooth multi angles edge and pointed finishing edge was produced as a result of some trials. Developed drill bit achieved required performance and contributed to large cost reduction, labor hour saving, production speed increase and work environment improvement.
2013-09-17
Technical Paper
2013-01-2202
Jonathan G. Pelham, Ip-Shing Fan, Ian Jennions, Jim McFeat
UAS (Unmanned aircraft system), widely known to the general public as drones, are comprised of two major system elements: an Unmanned Aircraft (UA) and a Ground Control Station (GCS). UAS have a high mishap rate when compared to manned aircraft. This high mishap rate is one of several barriers to the acceptance of UAS for more widespread usage. Better awareness of the UA real time as well as long term health situation may allow timely condition based maintenance. Vehicle health and usage are two parts of the same solution to improve vehicle safety and lifecycle costs. These can be worked on through the use of two related aircraft management methods, these are: IVHM (Integrated Vehicle Health Management) which combines diagnosis and prognosis methods to help manage aircraft health and maintenance, and FOQA (Flight Operations Quality Assurance) systems which are mainly used to assist in pilot skill quality assurance.
2013-09-17
Technical Paper
2013-01-2249
Christian Modest, Frank Thielecke
This paper presents a model-based approach for the multi-objective design of optimized diagnosis functions for high lift actuation systems. These systems are used to augment lift at low speed during takeoff and landing, and are safety critical. This demands requirements to the detection of failures and the isolation of root causes in order to provide a high availability at low risk. Dedicated functions cover the determination of features, the detection of symptoms and the isolation of root causes by means of inference and resolution. The aim of the design approach is to provide these functions in an optimal manner with respect to multiple objectives. In order to be clear and traceable the approach consists of separate consecutive steps. These are arranged by using systems engineering principles. With respect to requirements, models of different levels of detail are developed and used to design stepwise all required functions.
2013-09-17
Technical Paper
2013-01-2182
Marc Olivas, Jérôme Genoulaz, Luca Incarbone
In this paper, we present a new application of electromagnetic topology to model the channel formed by an aircraft harness to develop fault detection and localization. This method allows the numerical simulation of reflectometry signals for any kind of wired uniform and non-uniform.
2013-09-17
Technical Paper
2013-01-2220
M. Reza Mofakhami, Jerome Pinsonnault
In civil aviation the main driver for Structural Health Monitoring (SHM) is to provide maintenance and ownership benefits. The maintenance benefits are defined in terms of improving maintenance planning, increasing inspection intervals and reducing inspection cost. The ownership benefits can be measured in residual value and life extension. In this paper different aspects of SHM implementation are discussed for fatigue monitoring and fatigue damage sensing with a consideration of minimizing challenges for SHM implementation. First, the current Fatigue Monitoring implementation scenarios for the most representative agile military aircraft are reviewed. In the following some aircraft utilization results obtained from analyzing different airlines are presented. The obtained results show a better possibility of categorizing fleet of an airline in comparison with agile military aircraft.
2013-09-17
Technical Paper
2013-01-2146
William Bense
Operational reliability of aircraft engines can be increased if one can detect signs of damages before failure. Prognosis and Health Monitoring (PHM) consists in detecting these signs, and giving the probability of equipment anomaly at a defined horizon. This article presents a global overview of PHM systems. Using a system engineering approach, the needs and the equipments to monitor are clearly specified. The dedicated algorithms and embedded / ground systems split are then defined. Embedded system is mainly limited to data acquisition and data reduction. Ground system contains most of the algorithmic part. First, embedded indicators are normalized in order to be compared flight by flight. Then several kinds of approach can be applied to these indicators: among them, trend analysis toward a predefined threshold or anomaly detection. When an anomaly is detected, a classification algorithm identifies failure signature and associated equipment.
2013-09-17
Technical Paper
2013-01-2333
Ravi Rajamani, Abhinav Saxena, Frank Kramer, Michael Augustin, J.B. Schroeder, Kai Goebel, Ginger Shao, Indranil Roychoudhury, Wei Lin
The term Integrated Vehicle Health Management (IVHM) describes a set of capabilities that enable sustainable and safe operation of components and subsystems within aerospace platforms. However, very little guidance exists for the systems engineering aspects of design with IVHM in mind. It is probably because of this that designers have to use knowledge picked up exclusively by experience rather than by established process. This motivated a group of leading IVHM practitioners within the aerospace industry under the aegis of SAE's HM-1 technical committee to author a document that hopes to give working engineers and program managers clear guidance on all the elements of IVHM that they need to consider before designing a system. This proposed recommended practice (ARP6883 [1]) will describe all the steps of requirements generation and management as it applies to IVHM systems, and demonstrate these with a “real-world” example related to designing a landing gear system.
2013-09-17
Technical Paper
2013-01-2106
Hitoshi Oyori, Noriko Morioka
With airlines increasingly directing their attention to operating costs and environmental initiatives, the More Electric Architecture for Aircraft and Propulsion (MEAAP) is emerging as a viable solution for improved performance and eco-friendly aircraft operations. This paper focuses on electric taxiing that does not require the use of jet engines or the auxiliary power unit (APU) during taxiing, either from the departure gate to take-off or from landing to the arrival gate. Many researchers and engineers are considering introducing electric taxiing systems as part of efforts to improve airport conditions. To help cut aircraft emissions at airports, MEAAP seeks to introduce an electric taxiing system that would reduce the duration for which engines and APUs operate while on the ground. Given this goal, the aircraft electrical system deployed for use at airports must rely on a power source other than the jet engines or APU.
2013-09-17
Technical Paper
2013-01-2250
Nayeff Najjar, James Hare, Paul D'Orlando, Gregory Leaper, Krishna Pattipati, Andre Silva, Shalabh Gupta, Rhonda Walthall
This paper addresses the issue of fault diagnosis in the heat exchanger of an aircraft Air Conditioning System (ACS). The heat exchanger cools the air by transferring the heat to the ram-air. Due to a variety of biological, mechanical and chemical reasons, the heat exchanger may experience fouling conditions that reduces the efficiency and could considerably affect the functionality of the ACS. Since, the access to the heat exchanger is limited and time consuming, it is preferable to implement an early fault diagnosis technique that would facilitate Condition Based Maintenance (CBM). The main contribution of the paper is pre-flight fault assessment of the heat exchanger using a combined model-based and data-driven approach of fault diagnosis. A Simulink model of the ACS, that has been designed and validated by an industry partner, has been used for generation of sensor data for various fouling conditions.
2013-09-17
Technical Paper
2013-01-2159
Luigi Di Palma, Assunta Sorrentino, Pasquale Vitiello, Carmelo Izzo
The target of this paper is to describe the SHM project developed at CIRA. In order to achieve the low weigh target in the MALE UAV structures, the SHM project has the target to setup a system that, being able to evaluate the current state of the structure, will enable minus conservative assumption in the composite structural design. A lamb wave based procedure has been developed in order to analyze the presence of a barely visible impact defect (BVID). The techniques for the damage detections of composite and metallic structures have been developed through extensive numerical-experimental analysis based on lambwave investigation by using piezoelectric sense- actuators. The use of SHM technology and methodology has shown the possibility to have a significant reduction in the structural weight. The technology has achieved a TRL level between 4 and 5 and in order to achieve a higher TRL a test on a component in relevant environment is planned at the end of 2014.
2013-09-17
Technical Paper
2013-01-2331
Jianhua Ge, Brian Lefevre, Michael Roemer, Rodney Martin
This paper presents a novel health monitoring and fault adaptive control architecture for an unmanned hexrotor helicopter. The technologies developed to achieve the described level of robust fault contingency management include; 1.) A Particle Swarm Optimization (PSO) routine for maximizing the “built-in” fault tolerance that the closed loop flight control system affords, 2.) A two-stage Kalman filter scheme for real-time identification of faults that are masked by control system compensation, and 3.) A reconfigurable control allocation method which compensates for large degradations of the six main motor/rotor assemblies. The fault adaptive control system presented herein has strong robustness against small faults without the need for controller reconfiguration, and strong tolerance of large faults through adaptive accommodation of the fault source and severity.
2013-09-17
Technical Paper
2013-01-2332
Lucas Campos Puttini
This paper discusses the correlation of IVHM (Integrated Vehicle Health Management) as an emerging aerospace discipline and the Big Data paradigm widely discussed in the Information Technology industry. The 4-V model is discussed to qualify a Big Data problem in terms of the volume, variety, velocity and veracity of the data involved. Big Data management allows, for example, correlations to be found to “spot business trends, determine quality of research, prevent diseases, combat crime, and determine real-time roadway traffic conditions”. Examining these two fields side by side is necessary and desirable because innovation is very likely to occur when and where different but correlated domains interface. This paper compares the most significant technical components required for Big Data Analytics and IVHM to work.
Viewing 151 to 180 of 4781