Browse Topic: Railway vehicles and equipment

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Electric Vehicle Power Transfer System Using Conductive Automated Connection Devices Vehicle-Mounted Pantograph (Bus-Up)J3105/2_202001 (Current)1/20/2020
This document details one of the connections of the SAE J3105 document. The connections are referenced in the scope of the main document SAE J3105. SAE J3105/2 details the vehicle-mounted pantograph, or the bus-up connection. All the common requirements are defined in the main document; the current document provides the details of the connection. This document covers the connection interface relevant requirements for an electric vehicle power transfer system using a conductive automated charging device based on a conventional rail vehicle pantograph design. To allow interoperability for on-road vehicles (in particular, buses and coaches), one configuration is described in this document. Other configurations may be used for non-standard applications (for example, mining trucks or port vehicles).
Hybrid - EV Committee
SAE STANDARDS NEWS20AUTP02_061/1/2020
SAE publishes On-Route Mechanized Conductive EV Charging Systems Recommended Practices SAE International published SAE J-3105 Electric Vehicle Power Transfer System Using Conductive Automated Connection Devices Recommended Practice in January 2020. The document promotes the safe testing and performance of mechanized conductive power transfer systems. Written for buses and heavy-duty vehicles in general, SAE J-3105 encompasses the general physical, electrical, functional, testing and performance requirements for conductive power transfer primarily for vehicles using a conductive automated-charging-device (ACD) connection capable of transferring DC power. As the EV market expands, the need for the continued standardization of DC power distribution remains, and SAE J-3105 addresses three interfaces required to ensure power delivery is consistent. It defines a conductive power transfer method including the curbside electrical contact interface, the vehicle connection interface, the electrical characteristics of the DC supply and the communication system. It also covers the functional and dimensional requirements for the vehicle-connection interface and supply-equipment interface.
A Comparative Study to Assess the Effect and Cause of Ride Quality and Comfort of Passenger Vehicle with Subjective Correlation2019-28-241011/21/2019
Vehicle Dynamics testing has its importance in the fields of benchmarking and the validation of mathematical models built in order to predict the ride performance of the vehicle. The importance of enhancing the ride comfort is increasing day by day in present day scenario because of the long hours of driving experience. In presented work, the ride testing is done for two hatchback vehicles on highway conditions in order to compare the ride quality and ride comfort. The parameters like Vibration Dose Value, SEAT factor and Ride Diagram values are used to evaluate the ride comfort. After successful evaluation of the vibration levels affecting the ride comfort of the driver as well as the passenger the next major task is to identify and study the cause of the discomfort. The cause of the discomfort is studied and analyzed in terms of the complex motion of the vehicle. Vehicle motions like choppiness produces higher levels of discomfort as compared to the vertical movement of the vehicle. In order to correlate the objective test results with driver perception, subjective test is also carried out for four drivers for the same test conditions followed for the objective tests. Finally, a well-defined matrix is developed including all the parameters that affect the ride quality and ride comfort of the vehicle.
Deouskar, Aniruddha, Ramola, Rahul, Jha, Anuj
Analysis of the Tractor-Trailer Dynamics during Braking2019-01-21449/15/2019
The intensive development of tractor-building industry in the world has led to the widespread use of wheeled tractors and tractor trains in transportations on public highways. This requires an increase of engine capacity and speed of tractor trains, as well as strict demands for their braking systems. The formation of the necessary braking properties of wheeled tractors and tractor trains on their basis should be carried out at the design phase, taking into account a wide range of aggregated machines and tools. Blocking the wheels of the trailer with different sequence of their blocking and blocking the wheels of the tractor has significant impact on the total braking force, deceleration and stability of the tractor train. It is advisable to take this into account when modeling the braking process of a tractor train. The article deals with the braking dynamics of the tractor train and the impact of the dynamic distribution of normal reactions between the axles on the brake properties of the tractor train. The mathematical model of the braking process of the tractor-trailer train (consisting of a wheeled tractor and a two-axle trailer at the limit of blocking the wheels) has been obtained. The coefficients of the total braking force distribution between the to the front and rear axles of the tractor, front and rear axles of the trailer, ensuring the directional stability of the tractor-trailer train, have been determined.
Podrigalo, Mikhail, Klets, Dmytro, Kholodov, Mykhailo, Klimenko, Valeriy, Rudzinskyi, Volodymyr, Kholodov, Anton
Fast Accurate Non-Destructive Measurement of Absorber Impedance and Absorption2019-01-15846/5/2019
Cabin acoustic comfort is a major contributor to the potential sales success of new aircraft, cars, trucks, and trains. Recent design challenges have included the increased use of composites, and the switch to electrically powered vehicles, each of which change the interior noise spectral content and level. The role of acoustic absorption in cabins is key to the optimisation of cabin acoustic comfort for modern vehicles, with acoustic impedance data needed in order to assess and optimise the impact of each component of a given lay-up. Measurements of absorbing interior trim are traditionally performed using either sample holder tests in a static impedance tube (impedance and absorption), or through tests in reverberation rooms (absorption only). Both of these procedures present challenges. In-tube absorption and impedance measurements are destructive, requiring highly accurate sample cutting and sealing. Reverberation room absorption measurements are subject to the effects of varying room diffusion, along with the impact of edge diffraction, sample geometry, and location. Finally, while non-destructive methods using hand-held probes also measure absorption, they are not able to measure impedance accurately. This paper describes fast non-destructive tests using a portable flanged impedance tube, and how they be used to quantify and optimise the absorption of interior trims. Measurements are made on non-locally reacting lay-ups, with the results corrected to equivalent in-tube results using a flanged-to-sample holder correction factor. The corrected flanged tube results are then compared with baseline in-tube measurements. Discussions address data quality and how the non-destructive measurements may be used to optimise lay-ups for increased absorption.
Murray, Paul B., Alexander, Jon, Kunio, Jason, Larsen, Flemming
Aerodynamic Characteristics Simulation of Heavy Commercial Vehicles Passing through Expressway Tunnel in Cross Wind2019-01-06664/2/2019
Considering the aerodynamic characteristics of the vehicle traveling under the crosswind and the complexity of the flow field change, this paper uses overset mesh of STAR CCM+ software to carry out CFD simulation analysis on the aerodynamic characteristics of heavy commercial vehicles passing through the highway tunnel of which entrance and exit exist crosswind. Corresponding aerodynamic coefficients and flow field changes around the body at different crosswind speeds and different tunnel forms are monitored. The results show that the yaw moment is sensitive to the speed of crosswind. When a heavy commercial vehicle passes through a tunnel where crosswind increases from 10m/s to 13m/s,the yaw moment change rate increases from 34.8 kN•m/s to 45.9 kN•m/s. It also can be seen in these results is that when passing through two tunnels with a distance, the heavy commercial vehicle’s side force, roll moment and yaw moment change because of the surrounding periodic variation of flow field.
Ma, XiaoJing, Miao, ZhenHua, Ma, Jiayi, Zhang, Zhe, Ren, Linlin, Zhang, Yingchao
Autonomous Vehicle Engineering: January 201919AVEP011/8/2019
Editorial Trust, testing and transition SAE Standards News SAE updates J3016 automated-driving graphic View from a Visionary Chris Urmson helped give birth to vehicle autonomy. His company, Aurora, is leading the technology to maturity and widespread adoption. Extending EV Range Using AV Programming Intelligent programming of autonomous electric vehicles offers potentially big energy savings, according to a study by IAV. Intel Study: Autonomous Vehicles Expected to be Common-in 50 Years New U.S. consumer survey sees most Americans "expect" AVs, though many currently fear the technology. Europe's Latest AV Testing Facilities Key for Swift Autonomous Adoption The need for data sharing and commonality in burgeoning AV technologies is bringing new meaning to the words 'proving grounds.' End Public 'Shadow' Driving! The best way to test and train AI for autonomous vehicles is through proper simulation, systems engineering, and an end-state scenario matrix. A veteran engineer explains why the current AV testing paradigm must change. StreetDrone Offers Cost-Effective 'Mule' for AV Developers Two mobility-minded entrepreneurs make development of autonomous technology easier and more affordable for anyone. Predicting the Road to Efficiency Leveraging the building blocks of automated driving, Delphi's Intelligent Driving technology is designed to improve the efficiency and driving range of any vehicle. AV Regulations: Feds Ready to Get Their Claws Back? The new AV 3.0 federal guidelines for autonomous-vehicle development drew criticism for having no legal teeth. But they may only be the beginning. Florida's Babcock Ranch and the Future of Autonomous Communities An 18,000-acre development in southwest Florida seeks to be the model for short-range autonomous mobility and sustainable power for it all. Eying Mobility's Next Phases At the 2018 Los Angeles Auto Show, automakers and mobility experts examine mobility's ongoing transformation.
An Investigation of a Locomotive Structural Crashworthiness Using Finite Element Simulation02-11-04-001911/2/2018
In this article, the crashworthiness of a locomotive is assessed through finite element analysis (FEA). The present investigation is focused on the analysis of a locomotive with driving cab to improve the modeling approach and exploring the intrinsic structural weaknesses to improve its crashworthiness. The analyses are conducted according to the EN 15227 standard, which provide crashworthiness requirements for locomotive structure. The finite element model is validated in terms of acceleration and energy balance by the experimental results. The validated model is further used to assess the crashworthiness behavior at a higher impact speed, that is, 100, 160, and 225 km/hr. It has been noticed that local buckling occurs at different points, which reduces the desired progressive damage behavior in the locomotive. The results indicate that at higher speed, large plastic deformation occurs in the frontal part of the locomotive. The maximum deformation is 8.22 m which occurs at the speed of 225 km/hr.
Sharma, Sunil Kumar, Sharma, Rakesh Chandmal
Preliminary Study on Closed-Loop Acceleration Control of Motorcycles2018-32-005010/30/2018
In this study a preliminary investigation regarding closed-loop acceleration control for motorcycles is presented. Comprehensive considerations for the implementation of such a controller are discussed. Challenges, which are addressed, are a stable and sufficiently accurate measurement with the help of low-cost sensors and the consideration of the varying available maximum acceleration for set point calculation. In case of torque control, the maximum available torque is scaled by the throttle and thus automatically meets the limitation. Using acceleration as control variable, the varying set point limitation must be considered. According to current hypothesis, a precise closed loop control of the motorcycle longitudinal dynamics can be realized on the basis of the reference variable acceleration, yielding new possibilities in drive train control. The current control of the longitudinal dynamics is done by specifying a target output torque. However, the actual torque of the ICE is not available as a measured variable and is subject to a degree of uncertainty. In the case of a torque-based longitudinal dynamics control, the actual value can only be determined with great expense and thus a closed-loop control is not possible. Instead of the torque, the longitudinal acceleration can alternatively be used as a basis, since it is easier and less expensive to measure. The closed-loop acceleration control represents a methodology for use in future powertrains. For example, the potential use of hybrid powertrains in motorcycles raise new challenges for powertrain and vehicle control strategies. Compared to conventional drive configurations, at least two drive units contribute to the output torque, resulting in a higher control effort, which can be overcome by using acceleration control.
Winkler, Alexander, Grabmair, Gernot
Simulation Research of a Hydraulic Interconnected Suspension Based on a Hydraulic Energy Regenerative Shock Absorber2018-01-05824/3/2018
The current paper proposes a hydraulic interconnected suspension system (HIS) based on a hydraulic energy-regenerative shock absorber (HESA) comparatively with the passive suspensions. The structure and working principles of the HIS system are introduced in order to investigate the damping performance and energy regeneration characteristics of the proposed system. Then, the dynamic characteristics of the HIS-HESA system have been investigated based on a 4-DOF longitudinal half vehicle model. In the simulation, two different road inputs were used in the dynamic characterization of the HIS-HESA; the warp sinusoidal excitation, and the random road signal. In addition, a comparative analysis was provided for the dynamic responses of the half vehicle model for both the HIS-HESA and the conventional suspension. Furthermore, a parametric analysis of the HIS-HESA has been carried out highlining the key parameters that have a remarkable effect on the HIS-HESA performance. The dynamic performance evaluation includes both of the body acceleration and the pitch angle as the main analysis criteria of the vehicle dynamic performance. The results showed that the vehicle with the HIS-HESA system has good anti-pitch performance and excellent ride performance against the traditional suspensions. Moreover, the HIS-HESA suspension system can regenerate some of the dissipated power due to the damping process.
Zou, Junyi, Guo, Xuexun, Xu, Lin, Abdelkareem, Mohamed A. A., Gong, Bian, Zhang, Jie, Tan, Gangfeng
Videogrammetry in Vehicle Crash Reconstruction with a Moving Video Camera2018-01-05324/3/2018
In an accident reconstruction, vehicle speeds and positions are always of interest. When provided with scene photographs or fixed-location video surveillance footage of the crash itself, close-range photogrammetry methods can be useful in locating physical evidence and determining vehicle speeds and locations. Available 3D modeling software can be used to virtually match photographs or fixed-location video surveillance footage. Dash- or vehicle-mounted camera systems are increasingly being used in light vehicles, commercial vehicles and locomotives. Suppose video footage from a dash camera mounted to one of the vehicles involved in the accident is provided for an accident reconstruction but EDR data is unavailable for either of the vehicles involved. The literature to date describes using still photos to locate fixed objects, using video taken from stationary camera locations to determine the speed of moving objects or using video taken from a moving vehicle to locate fixed objects. However, techniques to evaluate the position, speed and acceleration of moving objects seen in video taken from moving locations have not been evaluated. To address the increasing prevalence of dash cams and other in-vehicle video and the value in using such video in vehicle crash reconstruction, this paper describes techniques for determining the position and speed of a moving object from digital video taken from a moving vehicle. Evaluations of the accuracy of those techniques were done when provided three different levels of information about the environment: 1 Aerial Photography (USGS) 2 Survey Data (Total Station) 3 3D Scan Data (of both the environment and vehicles)
Manuel, Emmanuel Jay, Mink, Richard, Kruger, Daniel
Development of New Hybrid Transaxle for Mid - Size Vehicle2018-01-04294/3/2018
The new P710 hybrid transaxle for a mid-size 2.5-liter class vehicle was developed based on the Toyota New Global Architecture (TNGA) design philosophy to achieve a range of desired performance objects. A smaller and lighter transaxle with low mechanical loss was realized by incorporating a new gear train structure and a downsized motor. The noise of the P710 transaxle was also reduced by adopting a new damper structure.
Matsumura, Mitsutaka, Shiozaki, Kazuya, Mori, Nobuhito
Rubber Suspension Bushing Model Identified by General Design Parameters for Initial Design Phase2018-01-06934/3/2018
This article proposes a rubber suspension bushing model considering amplitude dependence as a useful tool at the initial design phase. The purpose of this study is not to express physical phenomena accurately and in detail and to explore the truth academically, but to provide a useful design method for initial design phase. Experiments were carried out to verify several dynamic characteristics of rubber bushings under vibration up to a frequency of 100 Hz, which is an important frequency range when designing ride comfort performance. When dynamic characteristic theory and the geometrical properties of the force-displacement characteristic curve were considered using these dynamic characteristics as assumptions, an equation was derived that is capable of calculating the dynamic stiffness under an arbitrary amplitude by identifying only two general design parameters (dynamic stiffness and loss factor) under a reference amplitude. The rubber suspension bushing model was then constructed by transforming this equation. Two verifications were carried out to confirm that the model is capable of reproducing measured bushing characteristics. Previous models consist of a large amplitude stiffness component and an artificially created friction component, and must be identified using three unknown values. In contrast, the proposed model only consists of a function derived theoretically from the above assumptions. Consequently, this model can be identified using the two unknown values described above, which are general design parameters used by suspension engineers in everyday design work.
Horiuchi, Kentaro, Sakaguchi, Shinichi
Time-Varying Loads of Co-Axial Rotor Blade Crossings2017-01-20249/19/2017
The blade crossing event of a coaxial counter-rotating rotor is a potential source of noise and impulsive blade loads. Blade crossings occur many times during each rotor revolution. In previous research by the authors, this phenomenon was analyzed by simulating two airfoils passing each other at specified speeds and vertical separation distances, using the compressible Navier-Stokes solver OVERFLOW. The simulations explored mutual aerodynamic interactions associated with thickness, circulation, and compressibility effects. Results revealed the complex nature of the aerodynamic impulses generated by upper/lower airfoil interactions. In this paper, the coaxial rotor system is simulated using two trains of airfoils, vertically offset, and traveling in opposite directions. The simulation represents multiple blade crossings in a rotor revolution by specifying horizontal distances between each airfoil in the train based on the circumferential distance between blade tips. The shed vorticity from prior crossing events will affect each pair of upper/lower airfoils. The aerodynamic loads on the airfoil and flow field characteristics are computed before, at, and after each airfoil crossing. Results from the multiple-airfoil simulation show noticeable changes in the airfoil aerodynamics by introducing additional fluctuation in the aerodynamic time history.
Schatzman, Natasha L., Komerath, Narayanan, Romander, Ethan A.
Comparison of a State of the Art Hydraulic Brake System with a Decentralized Hydraulic Brake System Concept for Electric Vehicles2017-01-25159/17/2017
The ongoing changes in the development of new power trains and the requirements due to driver assistance systems and autonomous driving could be the enabler for completely new brake system configurations. The shift in the brake load collective has to be included in the systems requirements for electric vehicles. Many alternative concepts for hydraulic brake systems, even for decentralized configurations, can be found in the literature. For a decentralized system with all state of the art safety functionalities included, four actuators are necessary. Therefore, the single brake module should be as cost-effective as possible. Previous papers introduced systems which are for example based on plunger-like concepts, which are very expensive and heavy due to the needed gearing and design. In this paper a comparison between a state of the art hydraulic brake system using an electromechanical brake booster, and a completely new decentralized hydraulic brake concept is presented. After introducing the two systems, the paper focuses on the question, what advantages can be achieved by a hydraulic actuation close to the wheel in comparison to a centralized system. Therefore, key figures, which have been introduced in previous work, will be used and extended to evaluate the systems and compare their performance. They are related to dynamics and efficiency, like time to lock (TTL), hydraulic efficiency and energy consumption. This overall rating approach can be a guideline for developers choosing and developing the ideal brake system concept for a target vehicle.
Riese, Christian, Verhagen, Armin, Schroeter, Simon, Gauterin, Frank
Micromachined Sensors Monitor Train Rails and Predict FailuresTBMG-272828/1/2017
Spinoff is NASA's annual publication featuring successfully commercialized NASA technology. This commercialization has contributed to the development of products and services in the fields of health and medicine, consumer goods, transportation, public safety, computer technology, and environmental resources.
The Analysis of the Stiffness-Damping Parameters of a H-Bahn Vehicle2017-01-18906/5/2017
H-Bahn ("hanging railway") refers to the suspended, unmanned urban railway transportation system. Through the reasonable platform layout, H-Bahn can be easily integrated into the existing urban transit system. With the development of urban roads, the associated rail facilities can be conveniently disassembled, moved and expanded. The track beam, circuits, communication equipment, and sound insulation screen are all installed in a box-type track beam so that the system can achieve a high level of integration and intelligence. The carriage of the modern H-banh vehicle is connected with the bogies by two hanging devices. The vehicle is always running in the box-type track beam; therefore there are less possibilities of derailment. Consequently, the key work focuses on the running stability evaluation and curve negotiation performance analysis. In order to study the factors affecting running stability, the different stiffness and damping parameters in the primary and secondary suspension system are assigned to calculate the running stability index. To begin with, the vertical and lateral mathematic -dynamics models of the vehicle are established. Moreover, based on the USA VI rail spectrum, the vertical and lateral input displacements of the rail can be developed. In addition, the time-domain acceleration responses calculated by the dynamics model are converted to the amplitude-frequency characteristic curves by the Fourier transform. Finally, the weighted Sperling index calculated by the corresponding frequency and amplitude can evaluate the vehicle running stability. From the results of the vertical running stability analysis, the vertical indexes Wz are less than 2.5 almost, so that the running stability belongs to Level 1. For analyzing the lateral vibration, the hanging device is regarded as a fixed rigid body connecting the vehicle body and bogies. From the results of lateral running stability analysis, the lateral index Wy increases with the lateral stiffness of the air spring (< 2.5 × 105), and Wy is more than 3.0 at some points. In order to analyze the curve negotiation performance, the statics model describing the lateral rolling condition is established. By solving the nonlinear equations describing the statics model, the rolling angles of vehicle body are calculated in different conditions. The stiffness of air spring and centrifugal acceleration should be controlled in the limited values for improving the curve negotiation performance.
Zhang, Xingyu, Yang, Bo, Zhang, Manchuang, Hu, Sanbao
Effect of Friction Torque on Electromechanical Brake System Dynamics2017-01-19026/5/2017
Actuator and roller screw mechanism are key components of electromechanical brake (EMB) system in automotive and aerospace industry. The inverted planetary roller screw mechanism (IPRSM) is particularly competitive due to its high load-carrying capacity and small assembly size. For such systems, friction characteristic and friction torque generated from rolling/sliding contacts can be an important factor that affects the dynamic performance as well as vibration behavior. This paper investigates the modeling and simulation of the EMB system in early design stage with special attention to friction torque modelling of IPRSM. Firstly, a step-by-step system model development is established, which includes the controller, servo motor, planetary gear train and roller screw mechanism to describe the dynamic behavior of the EMB system. Secondly, detailed analytical formulations are established to calculate the friction torque in the time domain for evaluating its influence on the EMB displacement dynamic response. Finally, the dynamic performance for the EMB system is simulated under various driving conditions. Simulation results show that the friction torque has a significant influence on system brake performance. Larger friction torque tends to increase the vibration level. A force control strategy is proposed to decrease the oscillatory movement caused by the friction.
Qiao, Guan, Liu, Geng, Shi, Zhenghong, Wang, Yawen, Ma, Shangjun, Lim, Teik
Bob Lutz: What makes a great engineer?16AUTP11_1311/1/2016
Throughout the 2016 documentary film Live Another Day about the fall and rise of the Detroit-3 automakers, former GM Vice Chairman Bob Lutz shows the insight and enthusiasm that made him one of the industry's most effective “product guys” for four decades. While Lutz, now 84, actually holds a marketing MBA, his practical knowledge of aircraft design, systems and aerodynamics learned as a U.S. Marine Corps fighter pilot combined with a life-long love of cars, motorcycles and aircraft made him, as he says, “a close friend of engineers and designers.” He spoke recently with editor-in-chief Lindsay Brooke. I've met many good engineers in my +30 years covering the industry. But what makes a great one?
Brooke, Lindsay
Modelling, Analysis and Simulation of Clutch Engagement Judder and Stick-Slip2016-01-235510/17/2016
Analytical and numerical study is carried out to study the behavior of stick-slip and judder phenomenon during engaging and disengaging of the automotive clutch. For this purpose, a four degree of freedom torsional power train lumped mass model is developed. This torsional vibration system includes engine-flywheel, clutch, gear box and vehicle drive line, which are connected to each other by shafts. Equation of motion of the system is developed and initially a stability analysis is carried out for various gradients of coefficient of friction using eigen value analysis. Later, a numerical simulation is carried out to analyze the judder and stick-slip phenomenon using commercially available mathematical tool MATLAB. It is observed that the clutch stick-slip is increased with increase in external torque and clutch pressure fluctuations.
Sivanesan, M, Jayabalaji, G
Battery Parameter Estimation from Recorded Fleet Data2016-01-236010/17/2016
Existing battery parameter model structures are evaluated by estimating model parameters on real driving data applying standard system identification methods. Models are then evaluated on the test data in terms of goodness of fit and RMSE in voltage predictions. This is different from previous battery model evaluations where a common approach is to train parameters using standardized tests, e.g. hybrid pulse-power capability (HPPC), with predetermined charge and discharge sequences. Equivalent linear circuit models of different complexity were tested and evaluated in order to identify parameter dependencies at different state of charge levels and temperatures. Models are then used to create voltage output given a current, state of charge and temperature. The average accuracy of modelling the DC bus voltage provides a model goodness of fit average higher than 90% for a single RC circuit model. Both single RC equivalent circuit model and R-equivalent circuit model produce goodness of fit at average 75 % or higher. The dual RC equivalent circuit model experienced larger errors in voltage estimations compared to single R and RC equivalent circuit models.
Arvidsson, Rickard, McKelvey, Tomas
Improvement of Practical Electric Consumption by Drag Reducing under Cross Wind2016-01-16264/5/2016
Reducing vehicle fuel consumption has become one of the most important issues in recent years in connection with environmental concerns such as global warming. Therefore, in the vehicle development process, attention has been focused on reducing aerodynamic drag as a way of improving fuel economy. When considering environmental issues, the development of vehicle aerodynamics must take into account real-world driving conditions. A crosswind is one of the representative conditions. It is well known that drag changes in a crosswind compared with a condition without a crosswind, and that the change depends on the vehicle shape. It is generally considered that the influence of a crosswind is relatively small since drag accounts for a small proportion of the total running resistance. However, for electric vehicles, the energy loss of the drive train is smaller than that of an internal combustion engine (ICE) vehicle. Therefore, drag represents a relatively larger proportion of the total running resistance. That makes it necessary to consider the influence of a crosswind in order to reduce electric power consumption in real-world driving. In this study, representative test conditions taking into account a crosswind were proposed for wind tunnel tests based on an analysis of U.S. market data such as vehicle speeds and wind speeds. The test results made clear the mechanism causing drag to change under the representative test conditions. The representative test conditions were calculated by the Monte Carlo method using real-world driving data. It was found that a yaw angle of 4 degrees is the most influential yaw angle. The mechanism causing drag to change was studied in wind tunnel tests. The factors affecting the change in drag were identified, and measures for reducing that change were examined.
Kawamata, Hideyuki, Kuroda, Satoru, Tanaka, Shingo, Oshima, Munehiko
Development of an Efficient Power Train Cooling System with Effective Utilization of Front End Opening for a Utility Vehicle2016-01-06524/5/2016
This paper reports a study on Charge air cooler effectiveness, Air intake pressure drop, Acceleration Performance and Rise over ambient temperature of a utility vehicle for different layouts of Inter cooler, radiator, condenser and fan module in order to finalize an efficient Power train cooling system layout. The main objective is effective utilization of front end opening area, eliminating inter cooler heat load on the radiator, so that radiator size, fan size and fan motor wattage can be optimized to achieve desired cooling performance requirements with the cooling system (CRFM) module. Effect of the intercooler effectiveness, Intake pressure drop, Vehicle acceleration performance and Rise over ambient temperature are studied and both the advantages and disadvantages of the proposals are discussed to finalize the better position of inter-cooler along with other engine cooling components.
Ranjan, Ravi, Brahmasani, Lakshmaiah, Khan, Parvej
Development of New Hybrid Transaxle for Compact-Class Vehicles2016-01-11634/5/2016
1 As the demand for so-called eco-cars has been increasing recently, new hybrid transaxle P610 has been developed to achieve outstanding fuel economy and an excellent driving performance. P610 was installed in the 4th generation Prius, the first car to implement TOYOTA's new development strategy, TNGA (Toyota New Global Architecture). In order to accomplish the goal, radical reduction of mechanical loss, size and weight, dual-axle motor structure are adopted to draw out the potential capability of the THS (Toyota Hybrid System) to the maximum extent possible. Furthermore, placing the compact power train low, which is realized by installed the PCU(Power Control Unit) on top of the transaxle, led to provide the low center of gravity of the vehicle and excellent driving performance.
Taniguchi, Makoto, Yashiro, Takahisa, Takizawa, Keiji, Baba, Shinichi, Tsuchida, Michitaka, Mizutani, Tatsuhiko, Endo, Hiroatsu, Kimura, Hiromichi
Aerodynamic Load Maps of Vehicle Shapes at Arbitrary Attitude2015-01-25749/15/2015
The interest in flying cars comes with the question of characterizing aerodynamic loads on shapes that go beyond traditional aircraft shapes. When carried as slung loads under aircraft, vehicles can encounter severe aerodynamic loads, which may also cause them to go into divergent oscillations that can threaten the vehicle and aircraft. Slung loads can encounter the wind at arbitrary attitudes. Flight test certification for every vehicle-aircraft combination is prohibitive. Characterizing the aerodynamic loads with sufficient resolution for use in dynamic simulation, has in the past been extremely arduous. Sharp changes that drive instabilities arise over small ranges of yaw and pitch. With the Continuous Rotation technique developed by our group, aerodynamic load characterization is viable and efficient. With two well-chosen attitude sweeps and appropriate transformations, the entire 6-DOF load map can be obtained, for several rates. The paper describes application of the method to scale models of various vehicles of interest, and the decomposition of the air load features into various fluid dynamic phenomena. Rate effects are also measured and investigated using both 6-DOF load measurements at varying rates of motion, and hot-wire anemometry data from the wake. Generalized aerodynamic load prediction by reference to canonical shapes, is explored. Unsteady effects are conclusively shown to be absent. Starting with generalized empirically-based load prediction for cylinders and rectangular shapes that we have already demonstrated, the uncertainty in load prediction for some vehicles of interest is examined. Models of a truck, a HumVee and a Sentinel vehicle reminiscent of a Tactical Response Vehicle, are used as examples.
Motahari, Nicholas R., Turbeville, Franklin, Hiremath, Nandeesh, Komerath, Narayanan
System for Recirculation of Mobile Tooling2015-01-24949/15/2015
Aircraft assembly systems which require tooling or machinery to pulse or move between multiple positions within a factory can be positioned with high repeatability without high performance foundations or sweeping out large areas of floorspace. An example shows a system of large left and right-hand frames which are positioned at 3 sequential manufacturing steps and then recirculated to the start of production via a central return aisle. The frames are 41 ton actual weight and are 72′ long, similar to a rail car. The system achieves rectangular motion for the recirculation path. The supporting and moving system incorporates low-cost rail in a floor with minimal preparation and simple to use controls. The system is also easily reconfigured if the manufacturing system needs to be altered to meet rate or flow requirements.
Hempstead, Benjamen D., Smith, Scott
Optimization of EV Mounting System Considering Power Train Torsion Control2015-01-22256/15/2015
Faced on transient vibration of EV, considering the characteristics of the electric drive system, active and passive integrated transient vibration control method of power train mounting system was proposed. Models of power train system and mounting system were established, modal characteristics were grasped by simulation and experiment. A feed-forward controller was constructed from the facet of active control, mounting system transient vibration and power train torsion vibration were reduced. Based on this, further optimization of mounting system was conducted from a passive control perspective. Results show that the active and passive integrated control method can effectively reduce the dynamic reaction force of mounting points, improve the vibration conditions of power train and vehicle body as well.
Yu, Peng, Zhang, Tong, Li, Jing, Chen, Shiyang, Guo, Rong
Interior Noise Design of a Light Rail Vehicle Using Statistical Energy Analysis2015-01-23006/15/2015
This paper addresses the NVH design of a light rail vehicle whose maximum allowable interior SPL levels at certain speeds are regulated and may vary between countries, states, and cities. The objective of this study was to predict sound pressure levels (SPL) at several interior locations across a wide range of frequencies and estimate if the current design configuration will meet the noise level limits. Statistical Energy Analysis (SEA) was used to predict interior SPL and to understand and rank the various noise contribution paths and give a better understanding of the physics of transmission and what types of design changes are most effective to reduce the overall interior SPL to meet targets. A typical light rail vehicle is composed of a frame-like structure covered by lightweight panels and with interior panels that are increasingly made from composites, sandwich, laminated, or honeycomb materials or extruded panels. These lightweight structures made from materials that have previously been used primarily in aerospace applications have modal characteristics and transmission properties that require more advanced modeling than for simpler monolithic panels. Evaluation of the dominant noise transmission paths from the dominant sources allows sensitivity studies to evaluate which noise paths are the best candidates for improvement to overall vehicle NVH and which parts may be candidates for cost and weight reduction without significant degradation of the acoustic performance. This paper describes the motivation for this study and the details of the light rail vehicle construction. The SEA modeling approach is discussed, including the modeling of the structures and the main contributing sources. The contribution path ranking and the interior SPL predicted by the SEA model at several target locations are presented and compared to measured interior SPL data. Conclusions about the results and recommendations for future work are given.
Fiedler, Robert, Musser, Chadwyck, Cuchý, Petr
Control Research of Power Train Torsional Vibration Based on Magneto-Rheological Fluid Dual Mass Flywheel2014-01-286710/13/2014
To research the torsional vibration damping characteristic of magneto-rheological fluid dual mass flywheel (MRF-DMF) and the control system in power train, the multi-degree power train torsional vibration model which contains MRF-DMF and semi-active fuzzy control model are built, then the damping characteristic of MRF-DMF in several conditions are gained and compared with MRF-DMF when no control system. The result indicates: the damping characteristic of MRF-DMF effect on power train when using control is better than without control in idle, speed up, slow down, ignition and stalling, while the damping characteristic is less obvious in constant speed because the simulation condition and damping moment relatively stable.
Chen, Zhiyong, Chen, Zhiyuan, Mao, Yang, Shi, Wenku, Zhang, Guihui
Safe and Eco Friendly Train Traction System with No Rails2014-01-22899/30/2014
In this research paper, a novel train traction system is described. In this system, the vehicle is lifted like a hovercraft by air cushion and the traction is achieved by using horizontally mounted all-wheel drive. Chance of derailment is completely eliminated and wherein even in the event of failure of few traction wheel stations during run, the train remains mobile with absolute safety even at high speeds. All-wheel drive traction is powered by overhead electrification to maintain high power to weight ratio and faster acceleration. In the present invention, no rail is used. This eliminates the enormous cost of laying the complex and expensive railway tracks. Other advantages include the lack of exhaust fumes and carbon emissions at point of use especially in countries where electricity comes primarily from non-fossil sources, less noise, lower maintenance requirements of the traction units. In case, where the availability or laying the overhead electrification is an issue, the present invention has the potential to adopt alternate power sources such as petrol or diesel or gas turbine or jet engines or hybrid power sources for traction. But ecological issues may have to be compromised in such cases. The present invention has a potentially wide scope to revolutionize urban and suburban railway traction (both passengers and goods) and long distance traction. For proving the technical feasibility, a working model was developed. In this paper, the results from the working model are discussed in detail. (Indian patent and PCT application are pending).
Giridharan, K
Effects of Liquid Cargo on Lateral Stability of B-Train Combination2014-01-23199/30/2014
Road train vehicles have been applied as one of the common and efficient ways for transportation of goods, specifically hazardous liquid cargos, in different nations. These vehicles have a wide variety of lengths and towing systems such as the fifth wheel or the dolly draw-bar. Based upon specific regulations, they could be authorized to move on specific roads. In order to avoid hazard and danger in case of accidents, safety performance of a B-train vehicle as a specific type of road train vehicles is investigated in this paper. A Multi-Body Dynamic (MBD) model, which consists of a prime mover and two trailers coupled by fifth wheels, are simulated in the initial phase of the study. The developed dynamic model is capable of simulating required tests as well as the SAE lane change, along with a constant radius turn for the purpose of roll and yaw stability analysis and safety evaluation. The effects of variation of the fluid fill level are considered in this research. The trammel pendulum concept is adopted for simulation of fluid movements, known as sloshing, in two articulated tankers of the model. Moreover, a preview driver controller is integrated to the MBD model to provide the follow-up the path during the lane-change and constant radius turn maneuvers. Compared to the results from the simulation of fixed liquid cargo, the critical behavior of the vehicle in terms of rollover at lower speeds is observed when the movement of fluid is taken into account. The results show that transportation of a high density fluid yields a more critical condition compared to a low density one, when the same axle load is retained.
Hazrati Ashtiani, Iman, Abedi, Mehrnoosh
Green Wheel Loader - Operating Strategy of an Energy Efficient Hybrid Drive Train2014-01-24009/30/2014
Today's mobile machines still offer vast potentials regarding energy efficiency, which can be exploited by increasing the efficiency of drive train subsystems and optimising their interaction. Within the research project “TEAM”, the most promising drive train technology currently available is incorporated into a wheel loader in order to demonstrate the fuel savings possible through highly efficient subsystems and adapted operating strategies. This contribution gives an overview over the machine's drive train structure and explains the developed operating strategy in detail. Fuel saving estimations obtained by system simulation are shown. Furthermore, the intended use of the parallel hybrid and its impact on machine efficiency and functionality is discussed.
Schneider, Markus, Koch, Oliver, Weber, Juergen
Noise Synthesis of Electric Parking Brake using Vibration Analysis and Transfer Path Analysis2014-01-25159/28/2014
Prediction of noise and vibration of a gear train is important to achieve a competitive design. Objective of this paper is to develop a dynamic simulation model for vibration analysis and a synthesis process to predict vehicle interior noise using TPA (Transfer Path Analysis). The hybrid gear model is developed to simulate the stiffness of teeth and meshing characteristics in a gear pair. It is modeled by using the teeth stiffness map which is following real contact characteristics of a gear pair. The teeth stiffness is obtained by structural analysis. The multi-body model is composed of flexible bodies, shafts and nonlinear bearings. Input forces at the mounting point (input point) of the gear train are calculated by accelerations from dynamic analysis under real operating conditions. Calculated forces are used to synthesize a vehicle interior noise. Predicted noise is compared with experiment data.
Park, Jin kuk, Jung, Hyun Bum, Han, Min Gyu, Jeon, Nam ill
Advanced Materials for Aerospace and Space Applications2014-01-22339/16/2014
Constant swirls of innovative ideas are starting to push composites and hybrid metal-composite components for use in an ever expanding circle of products. Recent discoveries of Graphene/Au composites have invigorated innovations for its application to aerospace and space products. Attributes such as a low CTE, stiffness, and light weight attract other manufacturers of smaller products to use composites for enhanced performance and durability. The uses and economics of composites is an enormously broad subject. Examples of composite materials will be described in this paper to provide samples of applications selected for their far reaching potential to enhance product performance. Examples will also be presented to explain the application of carbon based composites where the product performance or application would not be possible without special materials. This paper will also describe emerging materials such as graphene and some of its applications to enhance the performance of current technologies It is easy become enamored with the composite big parts built for trains, planes, automobiles, ships, and wind turbine blades. We sometimes forget that there is a world of composites that exists outside these highly visible products where composites materials are contributing in substantial ways to other product's improvement. Many times the use of composites is integrated into the larger products in the form of components where tribology is critical to performance or coatings are needed to provide thermal protection.
Bullen, George Nicholas
Learning of Intelligent Controllers for Autonomous Unmanned Combat Aerial Vehicles by Genetic Cascading Fuzzy Methods2014-01-21749/16/2014
Looking forward to an autonomous Unmanned Combat Aerial Vehicle (UCAV) for future applications, it becomes apparent that on-board intelligent controllers will be necessary for these advanced systems. LETHA (Learning Enhanced Tactical Handling Algorithm) was created to develop intelligent managers for these advanced unmanned craft through the novel means of a genetic cascading fuzzy system. In this approach, a genetic algorithm creates rule bases and optimizes membership functions for multiple fuzzy logic systems, whose inputs and outputs feed into one another alongside crisp data. A simulation space referred to as HADES (Hoplological Autonomous Defend and Engage Simulation) was created in which LETHA can train the UCAVs intelligent controllers. Equipped with advanced sensors, a limited supply of Self-Defense Missiles (SDM), and a recharging Laser Weapon System (LWS), these UCAVs can navigate a pre-defined route through the mission space, counter enemy threats, and destroy mission-critical targets. Multiple missions were developed in HADES and a squadron of four UCAVs was trained by LETHA. Monte Carlo simulations of the resulting controllers were tested in mission scenarios that are distinct from the training scenarios to determine the training effectiveness in new environments and the presence of deep learning. Despite an incredibly large sample space, LETHA has demonstrated remarkable effectiveness in training intelligent controllers for the UCAV squadron and shown robustness to drastically changing states, uncertainty, and limited information while maintaining extreme levels of computational efficiency. Her specific architecture is applicable to a wide array of topics and specializes in problems with limited distributed resources in a spatiotemporal environment containing uncertainties and unknowns.
Ernest, Nicholas, Cohen, Kelly, Schumacher, Corey, Casbeer, David
Submersible Pressure Transducer for Tank Fluid Level MonitoringTBMG-197896/1/2014
Monitoring the level of liquid can be accomplished through the use of a pressure transducer. The density of the liquid and its height create pressure on the diaphragm of the pressure transducer to generate an accurate and cost-effective level measurement. Generally, pressure transducers can be used for level measurement from 10 inches of water column up to 10,000 PSI (700 bar).
Effects of Driver Acceleration Behavior on Fuel Consumption of City Buses2014-01-03894/1/2014
Approximately 50% energy is consumed during the acceleration of a city bus. Fuel consumption during acceleration is significantly affected by driving behavior. In this study, 13 characteristic parameters were selected to describe driving style based on analysis of how driving influences fuel consumption during acceleration. The 100,000 km real-world vehicle running data of six drivers on three city buses in a particular bus line in Tianjin, China were sampled using a vehicle-on-line data logger. Based on the selected characteristic parameters and collected driving data, an evaluation model of the fuel consumption level of a driver was established by adopting the method of decision tree C4.5. For two-level classification, the model has over 85% prediction accuracy. The model also has the advantages of having a few training samples and strong generalization. As an example of the model application, the fuel-saving potential of a driver under optimal operations was analyzed. Thus, the model can be used to train and evaluate drivers employed by bus companies.
Ma, Hongjie, Xie, Hui, Chen, Shuangxi, Yan, Ying, Huang, DengGao
Design Improvement of Differential Casing through CAE Strain Correlation2014-01-07564/1/2014
A differential casing is one of the important elements in the vehicle power train, whose objective is to house differential gears and take different loads coming from these gears. The function of a differential is to drive a pair of wheels while allowing them to rotate at different speeds. While taking a turn, the outer wheel needs to travel more compared to the inner wheel. This is possible due to the differential which rotates them at different speeds. This Paper highlights a simplified methodology to capture the differential casing failure and to resolve the same. The methodology adopted was then correlated with the test measurements to increase the confidence. During physical tests, strains are measured at different orientations of the differential casing and correlated with simulation results.
Londhe, Abhijit, Kangde, Suhas, N, Sreenadh
Experimental Determination of Rigid Body Properties of a Powertrain Unit for NVH Refinement2014-01-00394/1/2014
This paper establishes quick and accurate methods to experimentally determine the rigid body properties of a powertrain unit namely, the centre of gravity, the moment of inertia and the torque roll axis and also the rigid body dynamics of mounting system such as the rigid body modes, kinetic energy distribution, and elastic roll axis. The centre of gravity is determined using single point suspension and laser pointer to locate the axis passing through the centre of gravity. A special unifilar pendulum test rig is developed for determining the moment of inertia where an accelerometer measures the rotational oscillations for a given time period and the moment of inertia is determined by solving a set of inertial ellipsoid equations. An easy method of reorienting the powertrain is demonstrated in this paper. The torque roll axis is determined by generating a torsional excitation about the crankshaft axis of a freely suspended powertrain and by locating the centre of rotation of the powertrain in two different planes. The rigid body modes are determined by modal analysis on a standalone mounting arrangement required for proper excitation of the six degrees of freedom. After determining the translational and rotational modal frequencies, the kinetic energy is calculated for each mode frequency and the contribution of different modes at a particular frequency are determined. The elastic roll axis is determined in a similar manner as that of the torque roll axis; the difference in elastic roll axis estimation is that the powertrain is mounted on elastomeric mounts on a standalone test rig. The technique reduces the development time for power train mounting systems and also enhances vehicle design.
Frank, Jos, Manchi, Venkateshwararao, Raghavendran, Prasath
Gear Train Mesh Efficiency Study: The Effects of an Anti-Backlash Gear2014-01-17694/1/2014
In recent years, the focus on engine parasitic losses has increased as a result of the efforts to increase engine efficiency and reduce greenhouse gasses. The engine gear train, used to time the valve system and drive auxiliary loads, contributes to the overall engine parasitic losses. Anti-backlash gears are often used in engine gear trains to reduce gear rattle noise resulting from the torsional excitation of the gear train by the engine output torque. Friction between sliding surfaces at the gear tooth is a major source of power loss in gear trains. The effect of using anti-backlash gears on the gear friction power loss is not well known. As a part of the effort to reduce parasitic losses, the increase in friction power loss in the Cummins ISX 15 gear train due to the anti-backlash gear was quantitatively determined by modifying the methods given in ISO 14179-2 to fit the anti-backlash gear sub-assembly. A test case with a two gear mesh arrangement was designed for the purpose of validating the analysis by rig testing. The torque required to drive the test case as a function of gear rotational speed was measured on the rig. The test plan consisted of two configurations: 1. the anti-backlash gear and a regular spur gear mesh, and 2. the anti-backlash gear replaced by a regular spur gear. An anti-backlash and spur gear from the gear train of the Cummins ISX 15 engine - for the heavy duty market - were used in the rig. Results revealed that the anti-backlash gear-regular spur gear mesh required a mean torque of approximately 5 Nm, whereas the regular spur-regular spur gear mesh only required a mean torque of approximately 0.75 Nm. The power losses for these configurations were found to be in good agreement with the analytical results obtained by using the equation for friction losses according to Mauz. The conclusions of this study will impact engineering decisions that must consider the advantages of an anti-backlash gear (e.g. reduced gear rattle noise) with its disadvantages (e.g. cost and increased friction).
Joshi, Yashodhan V., Kelleher, Jordan E.
Assessment of Planetary Gear Train with Multiple-Pinion Arrangements2014-01-17634/1/2014
The planetary gear train has been used as a core element for most of automatic transmissions (AT) due to its unique advantages: such as high power density, lower noise level, lower support bearing cost, and easier for mass production, compare to lay shaft or other types. In particularly, when multiple-pinion (MP) arrangement is used to accommodate flexible packaging design specifications. However, the planetary gear train does inherit a critical limit that is the lack of flexibility on gear ratio selection, because it needs to comply with certain constraints on tooth combination to meet gear train installation for assembly, load sharing for durability and phasing arrangement for noise concerns. To fully take the MP advantages for AT transmission applications, while increase the gear ratio selection was the primary motivation that prompted us to seek for some potential solutions on the MP arrangement. This report will provide the method for the proposed approach, and also reveal some of the associated assessment results.
Chen, Joseph Y.
Stabilization of Linear Motion of the Tracked Vehicle2013-01-23639/24/2013
Realization of potential high-speed qualities of transport tracked vehicles is limited to a number of dynamic phenomena in linear motion. The analysis of the test results of investigating controlled movement dynamics and vehicle operating experience shows that linear motion process is accompanied by essential axial vibrations of the body. When moving along the roads with slightly deformable covering and low adhesion properties the grip of caterpillars with the ground is unilateral constraint. In such conditions a lateral track shift with essential amplitude of random nature is observed, it leads to deviation of a directional angle of vehicle movement within the range of frequencies, which the driver is not able to compensate. Consequently, in order to negotiate the limited corridor the driver reduces travelling speed. The research objective is to increase safe speed of linear motion of the tracked vehicle along the roads with slightly deformable covering and limited adhesion properties. The objective in view is achieved by investigation of parametrical oscillations in relation to the vertical axis of the tracked vehicle body with the asymmetric characteristic of the power train; the oscillations are induced by asynchronous wave processes in the caterpillar drive. This work puts forward and proves the hypothesis that the most plausible reason of fluctuations is high asymmetry of linear elasticity of caterpillars with the silent blocks of the left and right sides. When the vehicle enters the turn the system asymmetry increases, as far as the length of a driving track run of the lagging side as well as its elasticity increases in 6 - 7 times. Various element stiffness of the mechanical system may cause initiation of self-oscillations and with periodically changeable stiffness they will be parametrical ones as well. Initiation of vehicle body fluctuations occurs due to wave processes in an unloaded track run.
Derzhanskii, Viktor, Taratorkin, Igor
Electric Thermal Management Architectures2013-01-21649/17/2013
The escalation of vehicle operating costs due to continuously rising fuel prices has prompted aircraft designers to focus on more energy efficient designs. Among the heavy energy consumers in aircraft operations, the thermal management system is one of the largest. This is especially true of the refrigeration system powered by engine bleed air power. With the push towards more electric vehicles, an entirely new trade space has been opened up with regards to electric thermal management and the cost of bleed air versus electrical power. Despite favorable energy savings, the electric approach has increased the burden on the propulsion engine shaft power extraction systems (gearbox and drive train), electrical generators, power conditioning units, and electrical distribution systems. This paper presents potential architectures which utilize energy recovery and integration principles to address the challenges on the power generating system. These architectures suggest unique features offering opportunities to reduce overall system weight and installation volume, all while providing improved vehicle efficiency as a result of bleed and ram air usage reduction.
Lui, Clarence, Dooley, Matthew
Implementation of Non-Contact Drives into a High-Rail, 7-Axis, AFP Motion Platform2013-01-22889/17/2013
Traditionally, automated fiber placement (AFP) motion platforms use rack and pinion drive trains coupled through a gearbox to a rotary motor. Extensive use of non-contact linear motors on a new AFP motion platform produces a quiet, low-maintenance system without sacrificing precision. A high-rail gantry arrangement allows dynamic performance improvements to machine acceleration and speed, while lowering power consumption costs and capital expenses. The seventh axis incorporated into the machine arrangement effectively produces an effective “five sides of a cube” work envelope, permitting complex spar and panel fabrication.
Ehinger, Peter, Faubion, Guy, Hooks, Joshua, Seever, Luke
Optical Device for Converting a Laser Beam Into Two Co-aligned but Oppositely Directed BeamsTBMG-168637/1/2013
Optical systems consisting of a series of optical elements require alignment from the input end to the output end. The optical elements can be mirrors, lenses, sources, detectors, or other devices. Complex optical systems are often difficult to align from end-to-end because the alignment beam must be inserted at one end in order for the beam to traverse the entire optical path to the other end. The ends of the optical train may not be easily accessible to the alignment beam.
Dynamic Programming-based Optimization of Control Variables of an Extended Range Electric Vehicle2013-01-14814/8/2013
A dynamic programming-based algorithm is developed and used for off-line optimization of range extended electric vehicle power train control variables over standardized certification driving cycles. The aim is to minimize the fuel consumption subject to battery state-of-charge constraints and physical limits of different power train variables. The control variables to be optimized include engine torque and electric machine speed, as well as a variable that selects the power train operating mode. The optimization results are presented for four characteristic certification driving cycles and characteristic vehicle operating regimes including electric driving during charge depleting mode, hybrid driving during charge sustaining mode, and combined/blended regime.
Cipek, Mihael, Čorić, Mirko, Škugor, Branimir, Kasać, Josip, Deur, Joško
Automatic Transmission Control Based on Estimation of Sporty Driving Intention2013-01-04834/8/2013
The purpose of this research is to develop an automatic shift control method that emulates an experienced driver's manual shift maneuver which enhances driving performance during sporty driving. Driver control maneuvers and vehicle behavior were observed throughout the process of braking, cornering, and accelerating out of a corner on a winding test track. Close correlations were found between driving maneuvers, longitudinal and lateral acceleration, and the selected engine speed. Based on the analysis, an index is proposed for estimating the intention of the driver to drive in a sporty manner. This index consists of the magnitude of acceleration in a friction circle and the maximum longitudinal acceleration restricted by the performance of the power train. An automatic transmission control based on the estimated driving intention was then developed to achieve the necessary and sufficient available force. This paper discussed the details of the experimental results and analytical studies.
Noumura, Shin, Matsumoto, Shogo, Tanahashi, Toshio
Application of Electric Servo Brake System to Plug-In Hybrid Vehicle2013-01-06974/8/2013
An electric servo brake system applied for use on electric vehicles was applied for use on plug-in hybrid vehicles in order to achieve fuel-savings together with good brake feel and enhanced operability for plug-in hybrid vehicles. The electric servo brake system is made up of highly accurate braking pressure control that functions cooperatively with regenerative brakes together with a structure in which pedal force is not influenced by braking pressure control. The configuration of these components enabled good braking feel even when the power train was being switched from one drive mode to another. Automated pressurization functions that are intended for plug-in hybrid vehicles and that operate with electric servo brake systems were also developed. These developed functions include stall cooperative control that functions cooperatively with the power train, regenerative coordinate adaptive cruise control, and hill-start assist. The application of these automated pressurization functions enabled the reduction of fuel consumption and enhancement of operability.
Ohkubo, Naoto, Matsushita, Satoshi, Ueno, Masayuki, Akamine, Kohei, Hatano, Kunimichi
A Review of Some Cooling Air Flow Measurement Techniques for Model Scale, Full Scale and CFD2013-01-05984/8/2013
Each component of a drive train generates waste heat due to its limited efficiency. This waste heat is usually released to an air flow guided through one or more heat exchangers. So, the realized cooling air volume flow is one important characteristic value during the vehicle development process. This paper presents some of the available techniques for the measurement of cooling air volume flow in the vehicle during the different stages of an aerodynamic development process in model scale and full scale. Additionally, it provides suggestions when comparing these experimental values to CFD results.
Kuthada, Timo
Comparative Evaluation of Turbochargers for High Horsepower Diesel-Electric Locomotives2013-01-09304/8/2013
Indian Railways have a fleet of high-horsepower diesel-electric locomotives rated at 2310 kW. These high horsepower diesel-electric locomotives have evolved from original design of 1940 kW locomotives. Adoption of new design turbochargers was essential for this upgrading efforts and a series of new design turbochargers were evaluated on the engine test-bed before their use on the diesel locomotives. The objective was to increase engine power output, improve fuel efficiency and limit thermal loading. Test-bed evaluation of different turbochargers was carried out for comparing five different turbochargers. Each turbocharger had different size nozzle ring, diffuser, turbine blade assembly, impeller and inducer. The compressor maps of turbochargers were used to plot the engine load lines and to calculate surge margins. The tests involved measuring critical parameters for various combinations of engine speed and load for every turbocharger. Some of these measured parameters were air inlet temperature to the compressor, peak firing pressures, inlet temperature to the turbine, cylinder head temperature, brake specific fuel consumption (BSFC), engine boost and air manifold temperature. This paper discusses the methods adopted for carrying out these evaluations and the results obtained thereof along with the decision criteria for making final selection of turbocharger for locomotives.
Gautam, Anirudh, Agarwal, Avinash Kumar
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