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2017-05-18
Journal Article
2017-01-9680
Husain Kanchwala, Pablo Luque Rodriguez, Daniel Alvarez Mantaras, Johan Wideberg, Sagar Bendre
Abstract In recent times, electric vehicles (EV) are gaining a lot of attention as they run clean and are environment friendly. Recent advances in the applications of integrating control systems in automotive vehicles have made it practicable to accomplish improvement in vehicle's longitudinal and lateral dynamics. This paper deals with a brief overview of current state of art vehicle technologies like direct yaw moment control, traction control and side slip control of EV. There are various controller algorithms available in literature with different torque vectoring strategies. As EV can be precisely controlled because of quick in hub wheel motor response times, therefore various torque vectoring strategies can be comfortably used for enhancing vehicle dynamics. Moreover, by using four independent in-wheel motors, several types of motion controls can be performed.
2017-03-28
Technical Paper
2017-01-0894
Nishant Singh
Abstract Improving fuel economy has been a key focus across the automotive industry for several years if not decades. For heavy duty commercial vehicles, the benefits from minor gains in fuel economy can lead to significant savings for fleets as well as owners and operators. Additionally, the regulations require vehicles to meet certain GHG standards which closely translate to vehicle fuel economy. For current state of the art fuel economy technologies, incremental gains are so miniscule that measurements on the vehicle are inadequate to quantify the benefits. Engineers are challenged with high level of variability to make informed decisions. In such cases, highly controlled tests on Engine and Powertrain dynamometers are used, however, there is an associated variability even with these tests due to factors such as part to part differences, deterioration, fuel blends and quality, dyno control capabilities and so on.
2017-03-28
Technical Paper
2017-01-1141
Bashar Alzuwayer, Robert Prucka, Imtiaz Haque, Paul Venhovens
Abstract Fuel economy regulations have forced the automotive industry to implement transmissions with an increased number of gears and reduced parasitic losses. The objective of this research is to develop a high fidelity and a computationally efficient model of an automatic transmission, this model should be suitable for controller development purposes. The transmission under investigation features a combination of positive clutches (interlocking dog clutches) and conventional wet clutches. Simulation models for the torque converter, lock-up clutch, transmission gear train, interlocking dog clutches, wet clutches, hydraulic control valves and circuits were developed and integrated with a 1-D vehicle road load model. The integrated powertrain system model was calibrated using measurements from real-world driving conditions. Unknown model parameters, such as clutch pack clearances, compliances, hydraulic orifice diameters and clutch preloads were estimated and calibrated.
2016-10-25
Technical Paper
2016-36-0211
Thiago Hoeltgebaum, Rodrigo de Souza Vieira, Daniel Martins
Abstract The competitiveness within the automotive sector increases constantly. Research institutes, universities and manufacturers are commonly trying to discover the new trends and to develop novel technologies. Nevertheless, it is important to understand if a certain technology is worth researching. In order to do that, a state of the art survey is necessary which is usually divided in two main groups: Literature Information and Market Analysis. The literature information regards papers, congress proceedings, books, among other types of formal publication. The market analysis is responsible to gather information within the manufacturers press releases, websites and events, for example. Even though, depending on the technology, those two topics are not enough to reveal the importance of a given technology. Therefore, it is necessary to search the patents database, where it is possible to find the development status of a device.
2016-10-25
Technical Paper
2016-36-0230
Guilherme Canuto da Silva, Paulo Carlos Kaminski
Abstract Automotive industries are undergoing a transformation of their manufacturing systems. Called by the German government as Industrie 4.0, this transformation is based on the evolution of traditional Embedded Systems-ES to Cyber-Physical Systems-CPS. In the next years such evolution will have to reach transitory stages, where ES and CPS should coexist for a determined period of time (ES-CPS). Based on this projection, this work compares ES with CPS, identifies the main differences between these systems and thus forms a transitory stage of automotive manufacturing for the next years. The work is structured as follows: Introduction section places the reader on the treated subject and presents the methodology of the work. Later, Industrie 4.0, Embedded Systems (ES) and Cyber-Physical systems (CPS) are defined. Once this is done, the analysis of ES-CPS transition is finished. Analysis results are presented and a representation of ES-CPS transition is proposed.
2016-10-25
Technical Paper
2016-36-0125
Luiz Bellatini, Leandro Alencar, Ricardo Malerman, Rogério Fernandes
Abstract The purpose of this paper is to share with the Product Engineering community relevant learnings on Internal Shift System for Manual Transmissions in order to promote transmission performance and eliminate potential concerns on shift quality and system durability for passenger cars. The subsystems in focus are the Manual Transmission Sliding Sleeve, Gear Fork, Rods and Synch Rings. One important shift ability response that directly affects customer satisfaction is the Gear Clashing. This is a noise and vibration phenomena resultant of parallel synch activation while gear is intended to be engaged. This phenomenon was determinate by lack of Gear Fork design characteristics, which allowed two forks displacement at same time during cross-shifting maneuvers. Through simulation analysis, which consists a detailed select and shift 3D stack-limit motion, an abnormal displacement of non-intended flyer fork displacement has been captured in a specific hardware under development.
2016-10-25
Technical Paper
2016-36-0127
Gustavo Siebert, Amilton Sinatora
Abstract The growing use of tribotest has been helping the researches to understand the actuation mechanisms of additives on the friction and wear control of engine parts. But, it is common to observe differences between the tribofilms formed in real situation from that obtained using tribotests. Furthermore, the automakers have difficulty to correlate the results obtained using tribotests with that performed using engines in dynamometers. For the piston ring/cylinder bore tribosystem is almost impossible to reproduce its real tribosystem using tribotests. Therefore simplifications are necessary and they affect the tribochemical behavior of the tribosystem. To understand how these simplifications and the test parameters affect the tribochemical behavior of the simplified tribosystem is critical to design a tribotest that correlate well with the real situation.
2016-10-25
Technical Paper
2016-36-0177
Fábio Coelho Barbosa
Abstract Public transport has been considered the preferred strategy to reduce congestion and pollution from urban road traffic. For low to medium capacity, bus systems are considered the most affordable and flexible mode. Currently, diesel based systems still dominate transit bus market, due to their high productivity, low deployment costs, technological maturity, operational reliability and flexibility (high daily ranges, fast refuelling and no infrastructure requirement along the routes). However, although some important improvements in engine technology and aftertreatment devices, enforced by emission standards improvements (Euro VI, US 2010 and those related), have been achieved, it is well known that there is a limit to cleaning exhaust diesel buses exhaust. In this context, transit authorities and operators have been under pressure to shift for more environmental friendly technologies.
2016-04-05
Technical Paper
2016-01-0883
Walter Mirabella, Francesco Avella, Marco Di Girolamo, Tim Abbott, Oliver Busch
Abstract A thorough bibliographic survey was carried out to collect literature-available information about blending octane numbers (BONs) of most widely used ethers by the refining industry (mainly MTBE and ETBE). The intention was to review the publicly reported BONs values, to suggest the most appropriate figures for future reference, while also understanding the causes of the differences. Summary tables feature all BON values, either explicitly reported in literature or calculated based on experimental results. Due to synergistic intermolecular interactions with hydrocarbons, BONs typically depend on base stock composition. The octane gain tends to grow as the paraffin content in the base stock increases. Moreover BONs tend to decrease as the octane numbers (ON) of the base stock increase.
2006-03-06
Technical Paper
2006
2002-11-05
Technical Paper
2002-01-2918
Vitaliy Yu. Nezym
The presence of tip clearance between rotating blades and casing produces unfavorable influences upon compressor stage performances. Application of abradable linings (inserts) in the casing above rotating blades reduces this tip clearance to practically zero. And the variant is spread enough when rotor blade tips make an entire annular recess (EAR) of approximately rectangular configuration (RC) in the meridional section of casing (of lining). Some researches proved that the presence of entire annular recess in abradable lining may compensate somewhat the influence of tip clearance between blade tips and casing baseline. Therefore it is possible to substitute abradable linings for entire annular recess of rectangular configuration specially manufactured in the casing.
2002-11-05
Technical Paper
2002-01-2924
Robert N. McGrath
This paper summarizes several years of research which considered the National Aeronautics and Space Administration's assertion that the Small Aircraft Transportation System (SATS) will be an economical alternative to automobile and airline travel, when considering the value of travelers' time. Performance was studied in the corporate aviation environment, using NASA's metric for cost effectiveness. Cost, cost effectiveness, and the sensitivity of cost effectiveness to key independent variables were examined. Analyses shed favorable light on NASA's premise.
2002-11-05
Technical Paper
2002-01-2923
David Berry
Aerospace engineers continually strive to identify materials which provide processing flexibility, reduce manufacturing costs, and prove durable in harsh environments. PEEK™ polymer, successfully displaces metals, traditional composites, and other plastics in a growing number of aerospace applications due to its exceptional properties and ability to be easily fabricated into high tolerance parts through multiple manufacturing techniques.
2002-11-05
Technical Paper
2002-01-2922
Thierry Miquel, Félix Mora-Camino
This paper proposes an analysis and comparison study between two different nonlinear control approaches to design a relative guidance mode for civil aircraft. The first investigated approach is based on feedback linearizing control, whereas the second investigated approach is based on optimal control. These two approaches are compared in terms of performances and complexity, including trajectory characteristics and communication requirements. It appears that both approaches are quite promising and deserve extensive studies for further refinement and validation.
2002-11-05
Technical Paper
2002-01-2929
Simon I. Briceño, Dimitri N. Mavris
Recent market studies indicate a renewed interest for a quiet Supersonic Business Jet (SBJ). The success of such a program will be strongly dependent upon the achievement of stringent engine noise, emissions and fuel consumption goals. This paper demonstrates the use of advanced design methods to develop a parametric design space exploration environment which will be ultimately used for the identification of an engine concept capable of satisfying acoustic levels imposed by FAR part 36 (stage IV) and NOx and CO2 standards as stated in the 1996 ICAO. The engine performance is modeled through the use of Response Surface and Design of Experiments Techniques, enabling the designer/decision-maker to change initial engine parameter values to detect the effects of the responses in a time efficient manner. Engine performance and engine weight results are obtained through physics-based engine analysis codes developed by NASA.
2002-11-05
Technical Paper
2002-01-2928
Mohsiul Alam
The AS900 is a 7,000-lbf-thrust class medium bypass turbofan for business jet and small regional transport aircraft. During initial development testing, high non-synchronous vibration (NSV) limited AS900 engine operation in the test cells. The NSV was associated with a substantial aft end motion involving both spools, the static structure, and the aft mount system. The aft mount was modified, which allowed the engine to run at its maximum power with a moderate level of NSV. However, the presence of NSV was perceived to be a customer satisfaction issue as a potential exciter of cabin noise in the aircraft. Therefore, a comprehensive analysis and test program was initiated to eliminate NSV from the AS900 engine. This paper presents the process of identifying the root cause of the NSV and its influencing factors, as well as the design changes to successfully eliminate it from the AS900 engine.
2002-11-05
Technical Paper
2002-01-2927
Ismael Fernández, Adam R. Krause, Dimitri N. Mavris
The success of business jets like the Citation X, the fastest civil aircraft in use after the Concorde, highlights the need for speed to improve business and globalization. Currently, developing a supersonic business jet has many technical and economical impediments. These obstacles include sonic boom, emissions and noise requirements problems that are easily meet or do not exist for subsonic aircraft. A baseline aircraft, defined by an optimization process, is the starting point for this study. However, this baseline aircraft does not meet the sonic boom, emissions and noise requirements, which are very strict. Companion studies to this one indicate that it may be possible to meet emissions and noise requirements, but it is clear that technology infusion is necessary for the future viability of this aircraft concept to succeed.
2002-11-05
Technical Paper
2002-01-2939
Francois Gau
Aircraft are aging. Wiring on aircraft is mostly inspected visually with little emphasis on non-destructive testing. Current “on-condition” practices are time consuming, costly and subject to human factors. Wiring should to be considered as a system on the aircraft and analyzed on a proactive basis, similar to the engines and the structure. New technologies are available to enable a wire integrity program.
2002-11-05
Technical Paper
2002-01-2931
Hampus Gavel
As the time between different development projects of new aircraft (a/c) extends, experienced personnel in the field of basic a/c system design are difficult to employ when being on the onset of a new design. Further on basic a/c system design is a field neglected in literature and in the educational system. A text is under development that summarizes the Saab experience of the complete fuel system design with respect to the fighter a/c Viggen and Gripen, the commuter a/c 340 and 2000, the trainer a/c SK60 and also the conceptual a/c B3LA. This paper is an extract of this text and describe early considerations that have to be made when designing a fuel transfer system. Emphasis is put on the top requirements on a/c level.
2002-11-05
Technical Paper
2002-01-2930
Michael Buonanno, Choongiap Lim, Dimitri N. Mavris
Market forecasts predict a potentially large market for a Quiet Supersonic Business Jet provided that several technical hurdles are overcome prior to fielding such a vehicle. In order to be economically viable, the QSJ must be able to fly at supersonic speeds overland and operate from regional airports in addition to meeting government noise and emission requirements. As a result of these conflicting constraints on the design, the process of selecting a configuration for low sonic boom is a difficult one. Response Surface Methodology along with physics-based analysis tools were used to create an environment in which the sonic boom can be studied as a function of design and mission parameters. Ten disciplinary codes were linked with a sizing and synthesis code by using a commercial wrapper in order to calculate the required responses with the desired level of fidelity.
2002-11-05
Technical Paper
2002-01-2944
Philip R. Kedrowski, Robert E. Wahl, Edward D. Clark
Over the past 20 years, gas turbine engine simulators have evolved into an integral tool for testing and certifying the electronic controllers of gas turbine engines. At Honeywell, this evolution has taken place on parallel paths. Namely, the simulators for testing the Auxiliary Power Unit (APU) controllers and the simulators for testing the propulsion engine controllers. Although at the same company, these paths implemented two unique approaches in their development. However, the underlying philosophy behind how these simulators are used is the same and unique to Honeywell. This work outlines these evolutionary approaches and gives light to Honeywell's successful approach to simulator design and implementation. In the early years, simulators were built solely as a tool for use in testing the hardware interface of the controllers and didn't significantly reduce the time performing tests on development engines.
2002-11-05
Technical Paper
2002-01-2945
Kevin D. Cluff, Joseph A. Scalise
This paper details the evaluation and implementation of Honeywell's End Item Temperature Test (EITT) process which functionally tests each production LRU at the customer-required temperature extremes. An aircraft system that formerly utilized 100% screening of electronic parts was selected for this process. A fixture was developed to allow the end item to be thoroughly tested while inside an environmental chamber. Using EITT, Honeywell replaced screening with EITT for specifically selected parts. The EITT adds thermal testing in addition to the normal environmental stress screening and acceptance test procedure steps. EITT also provides an effective tool for root cause failure analysis. The EITT-produced units (LRUs) were found to have 47% fewer IC removals than the previously built systems that were subjected to the 100% part screening. By reducing the part screening-caused damage, a 42% reduction was observed in mechanical damage such as bent leads.
2002-11-05
Technical Paper
2002-01-2942
Gordon J. J. Bartley, Andy M. Anderson, Kenneth B. Jones
Cabin air quality is of continuing importance [1]. Contamination of air with particulates or vapors has the potential of affecting the health of passengers and flight crew. Therefore, measures are required to maintain acceptable levels of cabin air quality. One potential source of cabin air contamination is lubricating oils used in the engines. Type II oils are required for the main engines, but Type I or Type II oils can be used for the APU, with Type I recommended by some engine manufacturers for its cold-start properties. Southwest Research Institutes (SwRI®) Department of Emissions Research used an internally developed analytical method called Direct Filter Injection/Gas Chromatograph (DFI/GC™) to analyze for volatile fractions of lubricating oil contaminants on Environmental Control System (ECS) components. Samples of two standard Type II aviation turbine lubricating oils were analyzed with the DFI/GC™ method and their spectra examined.
2002-11-05
Technical Paper
2002-01-2948
Craig F. Chang, Thomas E. Ulbricht
The objective of this paper is to present an Aircraft Landing Systems' (ALS) approach to the solution of the whirl vibration problem of aircraft brakes. The developed method utilizes the concept of asymmetry to break two friction coupled symmetric modes into two distinct and separated modes. The analytical derivation of the whirl vibration will be first discussed. A method of creating asymmetry will then be presented. Finally, experimental results will be presented that confirm the effectiveness of the technique to reduce aircraft brake whirl vibration.
2002-11-05
Technical Paper
2002-01-2949
James R. Phillips
A dynamical model of tire longitudinal slip, suitable for use in aircraft brake control system and antiskid design, is presented. The model differs from conventional mu–slip models in that it incorporates a single degree of freedom for tire stretch. Applications of the model in simulation, control synthesis, and stability analyses are described.
2002-11-05
Technical Paper
2002-01-2947
T. B. Walker, D. J. Steinke, K. L. Johnson
2002-11-05
Technical Paper
2002-01-2953
Colin M. Taylor
This paper examines why large aircraft engines are started the way they are today, and why that may all change in the not too distant future. Electric starting of aircraft engines and Auxiliary Power Units (APU) has been limited to 28 VDC battery systems, with starting power typically under 10 kW. Above this power level the very high battery currents, and resulting voltage drops, make the approach less and less practical. Large engines for commercial transports may require more than 100 kW to start so low voltage battery starting will not be an option.
2002-11-05
Technical Paper
2002-01-2954
Albert Qiu, Hassan Kojori, Bin Wu
This paper presents a summary of a university based research project sponsored by Honeywell for the development of sensorless control method for Brushless DC (BLDC) motors for industrial and aerospace applications. In particular, the development, test results and assessment of an advanced cost effective sensorless BLDC motor controller for aerospace applications are presented and discussed in detail. The motor is controlled by the method of detecting the back EMF instead of the usage of the rotor position or speed sensors. The implemented embedded controls utilize an ASIC with the main objective of enhancing reliability, fault-tolerance, power density and performance.
2002-11-05
Technical Paper
2002-01-2958
Christophe Hamel, Tom Judd, Ketan Nguyen, Bryan Rowe, Kevin Wohlers
2002-11-05
Technical Paper
2002-01-2951
Ratan Guha
Demand on the reliability of Electric Generators for Aerospace applications is assuming more importance everyday with the advent of “Fly-by-Wire” and “More-Electric-Aircraft” concepts. With today's high-powered avionics and sophisticated control systems, airline operators expect better performance and would no longer accept weak links in the system that need frequent maintenance. One of the weakest points in an electric generator is its reliance on rolling element bearings, which are subject to unpredictable and frequent failures. Huge redundancy and frequent maintenance ensure uninterrupted supply of electricity in an aircraft.
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