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Training / Education Classroom Seminars
This one day seminar presents an overview of seals and sealing system design for military and commercial aircraft. It is aimed to provide engineers having some previous actuator and control valve design background with an understanding of the general hardware groove standards, standard parts for static applications and how seal designs and sealing systems can be best used in dynamic reciprocating and rotary applications. Information will be provided regarding seal material and fluid compatibility, friction drag, expected wear rates depending on operating conditions and duty cycle, hardware surface finish and topography.
Training / Education Classroom Seminars
This four-hour short course intends to present an overview of electrically powered flight control actuation systems, covering commercial applications. The scope covers issues related to the mechanical design of actuators themselves, with limited reference to their control electronics. Additionally, this course will provide participants an understanding of the design considerations behind these actuation systems.
Training / Education Classroom Seminars
This four hour short course provides an overview of hydraulic system design of typical business and commercial aircraft. Topics will include the principles, system architectures, power sources, and the main components and technologies of hydraulic systems including hydraulic power generation, filtration, fluid storage, distribution, sensing and control. The step by step process of designing a hydraulic system will also be reviewed. Additionally, future trends in hydraulic systems will be discussed.
Training / Education Classroom Seminars
SAE International is pleased to offer this professional development seminar in conjunction with the SAE A-6 Aerospace Actuation, Control and Fluid Power Systems Committee meeting Oct. 20-23 Santa Barbara, CA. This 4 hour short course will provide an overview of the hydraulic components used on aircraft. There will be a brief overview of hydraulics, aircraft hydraulic systems, and aircraft flight controls. You will learn the function of each component used within the hydraulic system, and then look in depth at each component’s design.
Training / Education Classroom Seminars
Considerable attention has been given to the design and efficiencies of electric hybrid propulsion systems and energy storage technologies. Although they draw much less attention, hydraulic hybrid propulsion and regenerative braking systems for road vehicles are a cost effective alternative to electric systems and have relevance to important sectors of the passenger and commercial vehicle markets. In this two-day seminar, hydraulic hybrid vehicle systems and their potential will be examined using model based evaluations.
Training / Education Classroom Seminars
This 4 hour short course provides an overview of Power Electronics (PE) in use in modern transport aircraft. This course includes the context, principles, design drivers, and the main PE components of various flight applications, including those for harsh environments. This course is designed to deliver and demystify the basic theories and best practices of mechanical, electronics, thermal management, safety, reliability and maintainability disciplines. In addition, future trends in Power Electronics will be discussed.
Training / Education Classroom Seminars
This 4 hour short course offers an overview of aircraft hydraulic pumps focusing on their application in hydraulic systems, design and performance characteristics, and integration issues. These topics will examine the various pump technologies available for aircraft system applications, their design, performance and operational characteristics and limitations, and discuss the challenges and lessons learned in the integration of pumps in hydraulic systems.
2018-04-23 ...
  • April 23-25, 2018 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
Training / Education Classroom Seminars
Hydraulic brake systems, one of the most important safety features on many road vehicles today, must meet manufacturer and customer requirements in addition to Federal Motor Vehicle Safety Standards. This course will analyze automotive braking from a system's perspective, emphasizing legal requirements as well as performance expectations such as pedal feel, stopping distance, fade and thermal management. Calculations necessary to predict brake balance and key system sizing variables that contribute to performance will be discussed.
2011-04-12
Technical Paper
2011-01-0391
Quan Zheng, Bruce Church, Ken Defore
Electro-hydraulic actuation has been used widely in automatic transmission designs. With greater demand for premium shift quality of automatic transmissions, higher pressure control accuracy of the transmission electro-hydraulic control system has become one of the main factors for meeting this growing demand. This demand has been the driving force for the development of closed loop pressure controls technology. This paper presents the further research done based upon a previously developed closed loop system. The focus for this research is on the system requirements, such as solenoid driver selection and system latency handling. Both spin-stand and test vehicle setups are discussed in detail. Test results for various configurations are given.
2010-04-12
Technical Paper
2010-01-1200
Jyh-Shin Chen
Fully Flexible Valve Actuation (FFVA) systems provide maximum flexibility to adjust lift profiles of engine intake and exhaust valves. A research grade electro-hydraulic servo valve based FFVA system was designed to be used with an engine in a test cell to precisely follow desired lift profiles. Repetitive control was chosen as the control strategy. Crank angle instead of time is used to trigger execution to ensure repeatability. A single control is used for different engine speeds even though the period for one revolution changes with engine speeds. The paper also discusses lift profile extension, instantaneous lift profile switching capability and built-in safety features.
2013-09-24
Technical Paper
2013-01-2427
Lorenzo Serrao, Giulio Ornella, Gilberto Burgio, Ettore Cosoli
The paper illustrates the development of a hydraulic hybrid powertrain concept for off-highway vehicles, which is the result of a three-year program at Dana's advanced technology centers. Engineers have conducted extensive simulations and tests while equipping a demonstration vehicle to determine feasibility, develop advanced features, and quantify benefits of hydraulic hybridization for traction. The system concept and operation as well as its development process are illustrated, focusing the system engineering principles and on the model-based approach to system design, control, and energy analysis. Experimental results are provided.
2013-09-24
Technical Paper
2013-01-2352
Paul C. Niglas
The new RSDII (Reduced Stopping Distance, phase 2) regulation creates an increased emphasis by the heavy truck industry to ensure that brake systems are properly chosen and optimized. This regulation has led to vehicles being fitted with much more powerful brakes. However, despite the intent of these new brakes to provide larger braking forces for shorter stopping distances, the performance of vehicles is still limited by the maximum friction coefficient between the vehicle's tires and the road. In order to get the most out of these new brakes, it is essential that the entirety of the vehicle be taken into account. With the use of a hardware-in-the-loop simulation tool, this paper will present stopping data predictions from a variety of vehicles of varying brake torque and wheelbase. It will be shown how these factors change the way a vehicle behaves under panicked stopping situations.
2013-09-24
Technical Paper
2013-01-2349
Naseem A. Daher, Monika Ivantysynova
Modern on-road vehicles have been making steady strides when it comes to employing technological advances featuring active safety systems. However, off-highway machines are lagging in this area and are in dire need for modernization. One chassis system that has been receiving much attention in the automotive field is the steering system, where several electric and electrohydraulic steering architectures have been implemented and steer-by-wire technologies are under current research and development activities. On the other hand, off-highway articulated steering vehicles have not adequately evolved to meet the needs of Original Equipment Manufacturers (OEM) as well as their end customers. Present-day hydrostatic steering systems are plagued with poor energy efficiency due to valve throttling losses and are considered passive systems relative to safety, adjustability, and comfort.
2013-09-24
Technical Paper
2013-01-2347
Mikko Huova, Matti Linjama, Kalevi Huhtala
Hydraulic systems are widely used in working actions of mobile machines. They offer good power to weight ratio, robustness and relatively good controllability. However, there has been growing interest on the energy efficiency of such machines during recent years. Load sensing proportional valve control is a typical solution for multi-actuator systems leaving a significant margin for improvement of energy efficiency. Digital hydraulic valve system enables independent metering and reduces losses significantly without a need of complete redesign of the hydraulic system of such machine. Digital hydraulic valve system consists of parallel connected on/off-valves and offers deterministic operation which is crucial for successful implementation of independent metering. Four different digital hydraulic valve control approaches are analyzed in the paper: four-edge-control, four-edge control with pressurized tank line, five-edge-control and six-edge-controlled three-chamber-cylinder.
2004-03-08
Technical Paper
2004-01-1389
Liyun Zheng, Jeremy Plenzler
Vane type cam phasers have been widely used in internal combustion engines to vary valve timing to achieve purposes such as low emissions, greater torque, and higher horsepower. One of the primary concerns in using a vane phaser is its position holding ability when disturbances are present. Disturbances include cam torque oscillation, cam pulley speed fluctuation, oil pressure fluctuation, and engine acceleration or deceleration. Cam torque disturbance is the biggest contributor to phaser position error. This paper will first present the generic schematic of a variable cam phasing system and its challenges, followed by the characterization of the fluid dynamics of the vane phaser, with an emphasis on the effects of pressure, leakage, and oil aeration on the vane phaser fluid dynamics and its ability to reject cam torque disturbance.
2004-03-08
Technical Paper
2004-01-1031
Thomas C. Croft
A variety of factors require consideration throughout the seal selection process during the design of a hydraulic system. This work serves as a description of material and dimensional characteristics that should be utilized by design and maintenance engineers. Information is given regarding polymeric materials that are commonly used in the manufacture of sealing devices. For dimensional properties, equations and discussion are given to assist in determining the correct size and fit for seals. Practical information regarding failure analysis is presented as well.
2004-03-08
Technical Paper
2004-01-0835
J. Gholipour, M. J. Worswick, D. Oliveira
This paper examines the application of damage models in tube bending and subsequent hydroforming of AlMg3.5Mn aluminum alloy tubes. An in-house Gurson-based damage model, incorporated within LS-DYNA, has been used for the simulations. The applied damage model contains several void nucleation and growth parameters that must be determined for each material. A simpler straight tube hydroforming process was considered first to check the damage parameters and predicted ductility. Then the model was applied to a sequence of bending and hydroforming. The damage history from pre-bending was mapped to the hydroforming stage, to allow prediction of the overall ductility. The applied forming parameters in the simulation were based on data extracted during the experimental tests. Finally, the numerical results were compared to the experimental data.
2004-03-08
Technical Paper
2004-01-0847
Zi Lu, Philemon C. Chan
A test study of the sensitivity of airbag load at out-of-position (OOP) conditions was performed. The calibrated pneumatically driven Airbag Test Simulator (ATS) was used as the test platform to provide a large number of well-controlled repeat tests. Dummy responses were measured with parametric variations of dummy position, neck shield, airbag folding, airbag cover, and steering wheel effects. A selected airbag was used and tests were carried out using the Hybrid III and THOR dummies. The data were analyzed in detail to provide phenomenological understanding of the effects of some critical parameters affecting OOP loads and dummy responses. The results identify a number of critical parameters that can significantly affect dummy responses at OOP conditions.
2004-03-08
Technical Paper
2004-01-1322
A. J. Turner, K. Ramsay
With the drive toward more fuel efficient vehicles, the individual and combined efficiency of powertrain subsystems is increasingly important. Development of alternative transmission types (AMT, DCT, CVT) has brought significant benefits arising from an increase in the number of ratios, ratio span and unit efficiency. However, it is recognised that further potential lies in improving actuation technology in controlled transmissions, of all types. Since the economic benefit of further refinement of traditional hydraulic devices appears to be limited, it is suggested that alternative technology is required. This alternative would seek to further reduce parasitic energy consumption due to pumping and associated system losses and also improve poor duty cycle controllability, whilst enabling cooling of any slipping sub-elements.
2004-03-08
Technical Paper
2004-01-0652
Shingo Uozumi, Takao Taniguchi, Kazumasa Tsukamoto, Masahiro Hayabuchi, Tatsuya Iwatsuki, Satoru Kasuya
AISIN AW has developed a new six-speed automatic transmission TR-60SN for rear wheel drive (RWD) vehicles, for use in sports utility vehicles with high torque engines. This new TR-60SN has been developed based on the concept of improving fuel consumption and drivability while minimizing the number of component parts, and covering engine torque of 10 or 12 cylinders. To achieve this, TR-60SN utilizes component parts including gear train, torque converter, oil pump, and casing that have a completely new design. In addition, a new electric-hydraulic control unit has also been developed that offers both world class shift quality and a sporty shift feeling.
2004-03-08
Technical Paper
2004-01-0726
Patrick Tinchi Pang, David Agnew
The dynamic response time of a hydraulic brake system often comes into consideration when making decisions on system optimization or trade-offs in performance. A study of the relative importance of response time can be found in reference [1]. For the brake system engineer, it is desirable to know the impact that each of the system components contributes under varying conditions. To better describe and predict the fluid dynamics inside an automotive brake system, a model is set up to predict the pressure differential of the brake fluid through each brake component. A proposed method of testing in vehicle was used to quantify individual flow restrictions. The test results were compared to actual data for correlation. Knowing the individual flow characteristics of a brake systems components provides valuable information to the brake system engineer for the purpose of optimizing response time performance.
2004-03-08
Technical Paper
2004-01-1067
J. Z. Feng, F. Yu, Y. X. Zhao, G. Xu
In order to reduce the development time and cost of vehicle control systems, the co-simulation approach has been paid great attention recently, which combines the advantages of different software packages and provide the means of rapid iteration of control algorithm and insight into its effects on vehicle performance in design stage. This paper presents the design process of a controller for bandwidth-limited active hydro-pneumatic suspension employed by an off-road vehicle based on the co-simulation technology. First, a detailed multi-body dynamic model of the vehicle is established by using ADAMS/View software package. Second, aiming at achieving high ride quality and handling performance so as to increase the vehicle traveling speed even on rough terrain surfaces, a combined PID and fuzzy controller is designed for the bandwidth-limited active suspension system and then worked out by means of S-functions provided by Matlab/Simulink.
2004-10-26
Technical Paper
2004-01-2733
William P. Fornof
A coalescing filter is typically used in a compressed air system to remove liquid and oil aerosols. A coalescing filter is most efficient when located downstream of an air dryer. The air dryer removes most of the liquid oil condensed in the compressor discharge line. Measuring the percent of oil removed by a coalescing filter is useful for determining efficiency. This paper covers a laboratory method to reproduce oil aerosols much like the filter will see in an actual application. High duty cycles produce the maximum amount of oil from the compressor. The air dryer acts as pre-filter for the coalescing filter. The coalescing filter element and its associated housing should be tested as a unit since the element's inherent efficiency is effected by the design of the housing.
2004-10-25
Technical Paper
2004-01-3064
Hiroki Shimoyama, Shigeru Ikeo, Eitaro Koyabu, Ken Ichiryu, Suck-kyu Lee
In this study, we evaluate the effectiveness of the hybrid system using Constant Pressure Hydraulic System (CPS). In the city traffic, vehicles are required to start and stop frequently. Therefore, the engine often runs in its low efficiency area. So, we study the CPS hybrid vehicle. This paper shows the experimental and simulation results. The efficiency of this system depends on the performance of the hydraulic pump/motor. We investigate various methods to keep the operation of the pump/motor at the high performance point and compared the fuel economy with that of conventional vehicle.
2004-03-08
Technical Paper
2004-01-1386
J. W. G. Turner, M. D. Bassett, R. J. Pearson, G. Pitcher, K. J. Douglas
Electrohydraulic and electromechanical valve train technologies for four-stroke engines are emerging which allow much greater flexibility and control of the valve events than can be achieved using mechanically-based systems. Much of the work done on exploiting the benefits of these systems has been directed towards improving engine fuel economy and reducing emissions. In the present work a study has been made, using an engine simulation program, in to some of the possible benefits to engine performance that may be facilitated by the flexibility of fully variable valve train (FVVT) systems. The simulation study indicates that FVVT systems, limited by realistic opening and closing rates, provide sufficient range in the valve event duration and timing to enable the engine to produce very high specific outputs whilst achieving a high level of torque in the low- and mid-speed range.
2004-03-08
Technical Paper
2004-01-1638
Hiroshi Tsutsui, Takayuki Hisano, Akitomo Suzuki, Makoto Hijikata, Masatoshi Taguchi, Koichi Kojima
Recently, 5-speed automatic transmissions have become mainstream through the world, and 6-speed automatic transmissions have also been introduced in the market. Consequently, the issue of shift control is gaining importance, and a trend toward increasing number of gears in automatic transmissions has become apparent. On the other hand, weight saving and downsizing of the transmission, including the hydraulic control unit, are strongly required in order to promote fuel efficiency. To meet these requirements, an electro-hydraulic control unit offering sophisticated functionality desired in order to provide excellent shift quality. As an answer to these requirements AISIN AW developed two types of new 6-speed automatic transmissions in 2002: “TR-60SN” for RWD vehicles and “TF-60SN” for FWD vehicles. Both TR-60SN and TF-60SN have the same structural characteristics.
2004-03-08
Technical Paper
2004-01-1635
Hideaki Takahara, Hideki Yasue, Ryoji Habuchi, Tadashi Ishihara, Shigeo Tsuzuki, Jiro Maeda
As requirements for protecting the global environment are being heightened on a worldwide scale in recent years, the development of low fuel consumption technologies in order to inhibit the discharge of CO2 is an important issue for the automotive industry. Recently, Toyota has developed a Super CVT for the 1.3-to 1.5-liter class vehicles to further improve their fuel economy. This CVT has been adopted on vehicles equipped with the ‘idling stop system’. The ‘idling stop system’ automatically stops the engine when the vehicle is stopped and the transmission shift lever is in the ‘D’ position (e.g. when the vehicle is at a stoplight). This improves the fuel economy of the vehicle by eliminating fuel consumption while the vehicle is stopped. The conventional CVT poses unique conditions such as startoff time lag or shock after the engine is restarted. These conditions occur because the CVT oil pump cannot generate hydraulic pressure while the engine is stopped.
2004-03-08
Technical Paper
2004-01-1639
Cheolwan Kim, Chin-Yuan Perng, Dengfu Zhang
In this paper we describe the application of a CFD methodology to characterize the orifice flows over a wide range of flow conditions with various geometrical features commonly found in hydraulic control systems. There are three objectives in carrying out this study. First, apply CFD analyses to provide physical insight into the orifice flow physics and clarify the use of relevant engineering parameters critical to hydraulic control applications. Second, quantify orifice discharge coefficient with respect to orifice diameter ratio, cross-sectional shape, plate thickness, orifice entrance and exit geometries. Third, support physical test and establish building block elements for hydraulic system modeling. The results obtained from CFD calculations agree very well with available data published in professional handbooks and fluid mechanics related textbooks, especially in the high Reynolds number flow regime.
2013-01-09
Technical Paper
2013-26-0042
N. Prabhakar, P. Sripathy, S. E. Bharathiraja, K. Ayyappan
Leveling valves are typical pneumatic flow control valves which are fitted in the vehicle chassis to supply or deplete air pressure in the bellows so as to maintain the chassis always in a horizontal position, under the loaded or unloaded condition of vehicle or trailer. Therefore it is necessary to study the flow rate of air for different operating angles of leveling valve corresponding to the vehicle load. Filters are provided, one at the upstream and two at the downstream in order to prevent dust from entering into the valve and bellows. All flow control valves have an inherent flow characteristic that defines the relationship between ‘valve opening’ and flow rate under constant pressure conditions. Hence Computational Fluid Dynamics (CFD) can be utilized as a useful design tool to optimize the flow area of leveling valve and also to study the difference in pressure between upstream and downstream of a filter in order to push the fluid through the filters.
2013-01-09
Technical Paper
2013-26-0111
Parul Goyal, Gaurav Chaudhary, Nirmal N
A two-stage spool valve system is common in the hydraulic system of an off-road vehicle and used as hydraulics control element for controlling the hydraulic cylinder. Off-road vehicle industries mostly use a fixed-gain PID based controller for the flow control of the two-stage spool valve system. A hydraulic spool valve system exhibits highly nonlinear behavior, which makes it challenging to design a PID based controller to control its dynamics. This paper presents a method for the dynamic system model development of the two-stage spool valve system. This model will be useful to study the impact on the valve dynamics due to lubricating oil properties variation to avoid the potential system hazards and machine failure scenarios. An alternative control system design approach is also proposed based on the gain-scheduled control technique, wherein the non-linear dynamics of the valve system is linearized at different equilibrium points and PID gains are scheduled at these points.
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