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Technical Paper
2014-10-13
Chunshan Li, Guoying Chen, Changfu Zong
This paper presents a fault-tolerant control (FTC) approach for four-wheel independently driven and steered (4WID/4WIS) electric vehicles. An adaptive control-based passive fault-tolerant controller is designed to improve vehicle safety, performance and maneuverability when an actuator fault happens. The proposed fault tolerant control method consists of the following three parts: 1) a fault detection and diagnosis (FDD) module that monitors vehicle driving condition, detects and diagnoses actuator failures with the inequality constraints ; 2) a motion controller that computes the generalized forces/moments to track the desired vehicle motion using Model Predictive Control (MPC); 3) a reconfigurable control allocator that redistributes the generalized forces/moments to four wheels with equality constrained optimization. The FTC approach is based on the reconfigurable control allocation which reallocates the generalized forces/moments among healthy actuators once the actuator failures is detected.
Technical Paper
2014-09-16
Prashant Vadgaonkar, Ullas Janardhan, Adishesha Sivaramasastry
Performance of Avionics systems is dictated by the timely availability and usage of critical health parameters. Various sensors are extensively used to acquire and communicate the desired parameters. In the Present day’s scenario, sensors are configured with wired approach. Number of sensors is growing due to automation, increasing the accuracy of intended Aircraft functions. Sensors are distributed all over the Aircraft and they are connected through wired network for signal processing and communicating. LRU’s which are integrating various sensors also use wired approach for communication. The Key driver for Airline operational cost is fuel. Fuel quantity is a direct function of weight. Weight of cables contributes significantly to the overall weight of the aircraft. Use of wired network approach poses challenges in terms of cable routing, stray capacitances, noise and mechanical structure. This paper describes various merits and demerits of wired sensors and their interface techniques.
Standard
2014-08-11
SAE J1979 / ISO 15031-5 set includes the communication between the vehicle's OBD systems and test equipment implemented across vehicles within the scope of the legislated emissions-related OBD.
Standard
2014-07-29
This SAE Aerospace Information Report (AIR) describes the design approaches used for current applications of aircraft Brake-by-Wire (BBW) control systems. The document also discusses the experience gained during service, and covers system, ergonomic, hardware, and development aspects. The document includes the lessons that have been learned during application of the technology. Although there are a variety of approaches that have been used in the design of BBW systems, the main focus of this document is on the current state of the art systems.
Standard
2014-07-11
This specification covers minimum design and test requirements for aircraft tire inflation-deflation equipment for use on all types of aircraft. It shall be the responsibility of the airframe manufacturer to determine the compatibility of the requirement with the applicable aircraft and to specify requirements in excess of these minimums as necessary.
WIP Standard
2014-06-26
On-Board Diagnostic (OBD) regulations require passenger cars, and light and medium duty trucks, to support communication of a minimum set of diagnostic information to off-board “generic” test equipment. This document specifies the diagnostic data which may be required to be supported by motor vehicles and external test equipment for diagnostic purposes which pertain to motor vehicle emission-related data. SAE J1979 was originally developed to meet U.S. OBD requirements for 1996 and later model year vehicles. ISO 15031 5 was based on SAE J1979 and was intended to combine the U.S. requirements with European OBD requirements for 2000 and later model year vehicles.
Standard
2014-06-10
This SAE Aerospace Information Report (AIR) provides guidelines for the development of landing gear fatigue spectra for the purpose of designing and certification testing of Part 25 landing gear. Many of the recommendations herein are generalizations based on data obtained from a wide range of landing gears. The aircraft manufacturer or the landing gear supplier is encouraged to use data more specific to their particular undercarriage whenever possible.
Standard
2014-06-10
On-Board Diagnostic (OBD) regulations require passenger cars, and light and medium duty trucks, to support communication of a minimum set of diagnostic information to off-board “generic” test equipment. This document specifies the diagnostic data which may be required to be supported by motor vehicles and external test equipment for diagnostic purposes which pertain to motor vehicle emission-related data. SAE J1979 was originally developed to meet U.S. OBD requirements for 1996 and later model year vehicles. ISO 15031 5 was based on SAE J1979 and was intended to combine the U.S. requirements with European OBD requirements for 2000 and later model year vehicles.
Technical Paper
2014-05-09
John O. Manyala
The emergence of tougher environmental legislations and ever increasing demand for increased ride comfort, fuel efficiency, and low emissions have triggered exploration and advances towards more efficient vehicle gearbox technologies. The growing complexity and spatial distribution of such a mechatronic gearbox demands precise timing and coordination of the embedded electronics, integrated sensors and actuators as well as excellent overall reliability. The increased gearbox distributed systems have seen an increased dependence on sensors for feedback control, predominantly relying on hardware redundancy for faults diagnosis. However, the conventional hardware redundancy has disadvantages due to increased costs, weight, volume, power requirements and failure rates. This paper presents a virtual position sensor-based Fault Detection, Isolation and Accommodation (FDIA), which generates an analytical redundancy for comparison against the actual sensor output. The proposed FDIA scheme has been validated experimentally using an electro-hydraulic test rig and the gearshift simulation model, including the non-linear hydraulic actuator dynamics.
Standard
2014-04-09
To define a list of anomalies related to OBD Communications. Misinterpretations of various OBD Communications Standards and Recommended Practices have resulted in OBD “no-communications” situations in the field. This Information Report identifies the most prevalent of these.
Technical Paper
2014-04-01
Aleš Kolar, Ralf Cerna, Werner Hofegger, Christoph Pichler, Markus Riener, Nathan Murphy, Georg Zembacher
The correct information about legal demands of the On-Board-Diagnostic (OBD) system in a vehicle project is required throughout the entire development process. Usually, the main obstacle in succeeding is to provide the company's expertise of some few experts for all employees who work in OBD related projects. The paper describes the AVL solution for knowledge management and tool supported control system design and calibration: OBD System Development Database. The software enables the user to access the regulatory requirements for a specific application and legislation from past, present and future (proposed rule-making) point of view. Information concerning already available and stored monitoring concepts is linked to the requirements in order to re-use potentially suitable concepts and to enable an efficient knowledge exchange within the company. Also, various reporting functionalities are implemented, for example the listing and comparison of legal requirements and monitoring concepts.
Technical Paper
2014-04-01
Mohammed Farag, Matthias Fleckenstein, Saeid R. Habibi
Abstract Due to their high energy density, power density, and durability, lithium-ion (Li-ion) batteries are rapidly becoming the most popular energy storage method for electric vehicles. Difficulty arises in accurately estimating the amount of left capacity in the battery during operation time, commonly known as battery state of charge (SOC). This paper presents a comparative study between six different Equivalent Circuit Li-ion battery models and two different state of charge (SOC) estimation strategies. The Battery models cover the state-of-the-art of Equivalent Circuit models discussed in literature. The Li-ion battery SOC is estimated using non-linear estimation strategies i.e. Extended Kalman filter (EKF) and the Smooth Variable Structure Filter (SVSF). The models and the state of charge estimation strategies are compared against simulation data obtained from AVL CRUISE software. The effectiveness of the models and estimation strategies is then compared through a comprehensive evaluation for model complexity, model accuracy, and root mean squared error in state of charge estimation.
Collection
2014-04-01
Vehicle diagnostics deals with the development, delivery and execution of diagnostic procedures for vehicle systems. This technical paper collection will explore new technologies, processes and trends in the area of vehicle diagnostics.
Technical Paper
2014-04-01
Tomohiro Minagawa, Daiji Nagaoka, Hiroyuki Yuza, Teruo Nakada, Takeyuki Kamimoto
Abstract The filtration efficiency of a DPF drops when it suffers a failure such as melting and cracks during regeneration. And then, on-board diagnostics (OBD) device has become needed worldwide to detect a DPF failure. In the development of an OBD soot sensor, evaluation of the sensor demands a portable instrument which can measure the soot concentration for on-board and in-field use. Some of the emission regulations require the in-field emission measurements under normal in-use operation of a vehicle. This study is intended to develop a high sensitivity and high response portable smoke meter for on-board soot measurements and a reference to OBD soot sensors under development. The smoke meter accommodates a 650 nm laser diode, and its principle is based on light extinction in high soot concentration range and backward light scattering for low soot concentration measurement. Raw exhaust sample flows through a thermo-controlled optical tube at a flow rate of 3 liter/min, and the total system unit weighs only 16 kg.
Technical Paper
2014-04-01
Robert Cloudt
A particulate matter On-Board Diagnostics method based on temperature sensing is demonstrated. The concept applies a detection filter downstream of the main particulate filter and a flow diversion pipe. A small fraction of the main exhaust flow is diverted through the detection filter. In case the main soot filter has some leakage, soot will collect on the detection filter where it reduces the filter's permeability. As a result the diverted flow is reduced. This effect is sensed by a temperature sensor placed downstream of the detection filter because the change of diverted mass flow results in a change of heating rate. This principle allows particulate filter diagnostics based on cost-effective and readily available sensing technology. Comprehensive diagnostics software is developed to interpret and assess the temperature signal. The developed diagnostics software detects particulate filter filtration inefficiency and performs plausibility checks. The concept is demonstrated using an instrumented test vehicle with purposely damaged particulate filter.
Technical Paper
2014-04-01
Fabian Köpple, Dimitri Seboldt, Paul Jochmann, Alexander Hettinger, Andreas Kufferath, Michael Bargende
In order to comply with more and more stringent emission standards, like EU6 which will be mandatory starting in September 2014, GDI engines have to be further optimized particularly in regard of PN emissions. It is generally accepted that the deposition of liquid fuel wall films in the combustion chamber is a significant source of particulate formation in GDI engines. Particularly the wall surface temperature and the temperature drop due to the interaction with liquid fuel spray were identified as important parameters influencing the spray-wall interaction [1]. In order to quantify this temperature drop at combustion chamber surfaces, surface temperature measurements on the piston of a single-cylinder engine were conducted. Therefore, eight fast-response thermocouples were embedded 0.3 μm beneath the piston surface and the signals were transmitted from the moving piston to the data acquisition system via telemetry. Extensive parameter variations were performed, in order to investigate the influence of e.g. the rail pressure, the engine load and the engine speed on the surface temperature of the piston.
Technical Paper
2014-04-01
Timothy H. DeFries, Michael Sabisch, Sandeep Kishan, Francisco Posada, John German, Anup Bandivadekar
Fuel economy (FE) and greenhouse gas (GHG) emissions measured via chassis testing under laboratory conditions were never intended to represent the wide range of real-world driving conditions that are experienced during a vehicle's lifetime. Comprehensive real-world information is needed to better assess US FE label adjustments, determine off-cycle credits for FE standards, and forecast real-world driving behavior, fuel consumption, and CO2 emissions. This paper explores a cost effective method to collect in-use fuel consumption data using the on-board diagnostics (OBD) data stream in light-duty vehicles (LDVs). The accuracy of fuel consumption calculated from the OBD data was analyzed in two ways. First, fuel rates calculated from standard OBD Parameter IDs (PIDs) were compared with fuel rate estimates based on enhanced PID (OEM fuel injector fuel rate) data in two different vehicles. The cumulative fuel rate derived from standard PIDs was lower than the fuel rate values obtained from injector-based data (Enhanced PID) for the tested vehicles by approximately 3% and 13%.
Standard
2013-12-16
This SAE Aerospace Information Report (AIR) identifies current nondestructive inspection (NDI) methods used to ensure product integrity and maximize "in service" life of the major structural components of aircraft wheel and brake assemblies.
WIP Standard
2013-12-04
The scope of the test method is to provide stakeholders including fluid manufacturers, brake manufacturers, aircraft constructors, aircraft operators and airworthiness authorities with a relative assessment of the effect of deicing chemicals on carbon oxidation. This test is designed to assess the relative effects of runway deicing chemicals by measuring mass change of contaminated and bare carbon samples tested under the same conditions.
Technical Paper
2013-11-27
Suchismita Chatterjee, Arun Sivasubrahmaniyan
Misfires in SI engines are one of the major causes for increase in vehicle exhaust emissions beyond the regulatory limit. Misfires have a great potential to destroy catalytic converters due to increased exhaust temperatures caused by unburned fuel from the misfired cylinders. It also leads to decrease in engine efficiency and high fuel consumption. Misfires are majorly caused due to unfavorable spark plug temperatures, low ignition energy, fuel system malfunction, improper air-fuel mixture ratio, flame propagation speed, etc. Monitoring of misfire detection in SI engines is an essential requirement of On-Board Diagnostic (OBD) regulations in many countries. This paper compares the conventional and advanced misfire detection technologies in spark-ignition engines, available and under development for meeting the OBD regulations worldwide. It describes the misfire detection principle. Comparison of the methods is done considering system cost, system accuracy in detecting misfire, ease of implementation and conclusions are drawn.
Standard
2013-11-01
The focus of this SAE Aerospace Standard (AS) is the integration of thermally actuated pressure release devices, hereafter referred to as fuse plugs, with the wheel and brake assembly. It does not address the manufacturing, quality or acceptance test requirements pertaining to the production of these fuse plugs. It establishes minimum design, installation, qualification, and operational requirements for fuse plugs which are used only in tubeless tire type aircraft braked wheels. Fuse plugs are designed to completely release the contained inflation pressure from a tubeless tire and wheel assembly when brake generated heat causes the tire or wheel to exceed a safe temperature level. The objective is to prevent tire or wheel rupture due to brake generated heat that could cause an unsafe condition for personnel or the aircraft. (Reference: U.S. Department of Transportation FAA Advisory Circular No. 23-17C; Title 14, Code of Federal Regulations (14 CFR) Part 25.735 (j); U.S. Department of Transportation FAA Advisory Circular No. 25.735-1 and U.S.
Standard
2013-11-01
This SAE Aerospace Standard (AS) defines the requirements for brake systems used on military aircraft equipped with wheel-type landing gears.
Standard
2013-11-01
This document covers military aircraft wheel and hydraulically actuated brake equipment.
WIP Standard
2013-10-21
This Aerospace Information Report will summarize several existing aircraft landing gear shimmy analysis techniques and provide guidance on the synthesis and testing of tire properties, strut properties, and other landing gear mechanical properties that support the various shimmy analysis methods. This AIR is applicable to large and small fixed wing and rotary wing aircraft for military or civilian use.
Standard
2013-10-20
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