Browse Topic: Railway vehicles and equipment

Items (167)

2022-28-044611/09/2022

The ability to precisely control electrical voltages on a large scale has made possible many efficient, powerful innovations, from high-speed electric trains to wind turbines to electric drive motors for everything from heavy earthmoving equipment to personal electric vehicles (EVs). But the equipment that manages this process — including power inverters, thyristors and variable-speed drives — requires high-performance power electronics cooling. As temperatures rise, the efficiency, reliability, and life spans of these devices drop, and the power electronics inside HEVs and EVs are no exception. Advancements in power electronic thermal management technologies will enable next generation automotive to fulfill increasingly demanding mission objectives. DC-DC converter and inverter systems slated for higher performances, reliable and sustainable applications. Even with very high efficiencies, the components of these systems produce kilowatts of power loss in the form of heat. The current

Sahoo, Pranati

The Short-flight Alternative

22AVEP04_0804/01/2022

The Budget Airline Car is an EV alt-shuttle seating six adults, with luggage storage in each door. Short-haul airline flights can be a great convenience for travelers, but they produce more CO2 emissions - about 250 g/km per person - than any other form of passenger transportation, including compact EVs and electric trains. That's about 25% more emissions than long-haul flights, because short-hop flying uses proportionately more fuel at takeoff and landing. Could an automotive alternative offer a solution? That is what Car Design Research (CDR), a U.K.-based consultancy, set out to investigate, working with design associates Yichen Shu in China and Aditya Jangid in India. The resulting concept is the Budget Airline Car, one of six new passenger-vehicle types that CDR director Sam Livingston and his team feel would be enabled by new mobility technologies.

Kendall, John

Vanadium: A Green Metal Critical to Aerospace and Clean Energy

TBMG-3737608/01/2020

In the 1960s, the world’s leading aerospace engineers at Lockheed’s Skunk Works facility faced an extraordinarily difficult engineering challenge: how to design a successor to the U-2 spy aircraft, which had proven increasingly vulnerable to advanced Soviet anti-aircraft systems. Among other capabilities, the next-generation aircraft they were to design required an ability to cruise at a sustained speed of Mach 3+, operate at altitudes exceeding 80,000 feet, and feature as low a radar cross section as possible. Given the technologies of the day – slide rules were still used by engineers for most calculations – it was a daunting task.

Editorial

20AVEP05_0105/01/2020

Privately-owned vehicles were never so safe as they are today. Nor have they made so much sense. That thought hit me between the nostrils recently, as I sprayed a pungent disinfectant on the steering wheel of my family's B-segment runabout. Carefully wiping down the car's touch points with antibacterial cleaners has become a new pandemic ritual for us after returning home from food shopping and other essential missions. My little tribe generally keeps the interiors of our two vehicles tidy. Finding the occasional French fry buried in a seat track is, however, preferable to the dangerous microbes deposited every minute in the typical bus, train, or ride-share. The term “clean,” as understood by transit passengers, means a few spritzes by a custodial crew racing to meet uptime targets.

Brooke, Lindsay

Electric Vehicle Power Transfer System Using Conductive Automated Connection Devices Vehicle-Mounted Pantograph (Bus-Up)

J3105/2_202001 (Current)01/20/2020

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 NEWS

20AUTP02_0601/01/2020

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

A Comparative Study to Assess the Effect and Cause of Ride Quality and Comfort of Passenger Vehicle with Subjective Correlation

2019-28-241011/21/2019

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

Deouskar, Aniruddha, Ramola, Rahul, Jha, Anuj

Q&A

19TOFHP06_1506/01/2019

For years Volvo Construction Equipment has operated wheel loaders via remote control in underground mining operations, first for very dedicated tasks and more recently increasing the flexibility and scope of their operation. A recent test program with mining company Boliden examined both standard WiFi and a 4G+ communication system built with the help of Ericsson, on a machine located more than 400 m (1,300 ft) below ground. Though the program was deemed a great success by both companies and considered an important step on the pathway to truly autonomous machines, they agreed that a more robust communication system was necessary. Hello 5G. Volvo CE is now trialing 5G mobile connectivity in a two-year partner program by Telia and Ericsson, this time employing a remote-controlled wheel loader, the L180H, in a 25-hectare constructionsite setting in Eskilstuna, Sweden. Calle Skillsäter, Volvo CE's technical specialist for connected machines, offers some insights on the technology, this

Gehm, Ryan

Aerodynamic Characteristics Simulation of Heavy Commercial Vehicles Passing through Expressway Tunnel in Cross Wind

2019-01-066604/02/2019

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 2019

19AVEP0101/08/2019

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

An Investigation of a Locomotive Structural Crashworthiness Using Finite Element Simulation

02-11-04-001911/02/2018

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

Sharma, Sunil Kumar, Sharma, Rakesh Chandmal

Rubber Suspension Bushing Model Identified by General Design Parameters for Initial Design Phase

2018-01-069304/03/2018

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

Horiuchi, Kentaro, Sakaguchi, Shinichi

Simulation Research of a Hydraulic Interconnected Suspension Based on a Hydraulic Energy Regenerative Shock Absorber

2018-01-058204/03/2018

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

Zou, Junyi, Guo, Xuexun, Xu, Lin, Abdelkareem, Mohamed A. A., Gong, Bian, Zhang, Jie, Tan, Gangfeng

Time-Varying Loads of Co-Axial Rotor Blade Crossings

2017-01-202409/19/2017

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

Komerath, Narayanan, Schatzman, Natasha L., Romander, Ethan A.

Micromachined Sensors Monitor Train Rails and Predict Failures

TBMG-2728208/01/2017

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 Vehicle

2017-01-189006/05/2017

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

Zhang, Xingyu, Yang, Bo, Zhang, Manchuang, Hu, Sanbao

Bob Lutz: What makes a great engineer?

16AUTP11_1311/01/2016

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

System for Recirculation of Mobile Tooling

2015-01-249409/15/2015

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

Aerodynamic Load Maps of Vehicle Shapes at Arbitrary Attitude

2015-01-257409/15/2015

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

Motahari, Nicholas R., Turbeville, Franklin, Hiremath, Nandeesh, Komerath, Narayanan

Study on Independent Tuning Damping Characteristic by Coupling of Electromagnetic Dampers for Automobiles

2015-01-004403/10/2015

Methods for motion control with a coupled suspension systems of automobile have been proposed and their effectiveness has been shown by the previous studies. However, it is not easy to couple hydraulic dampers because it requires designing and manufacturing complex pipelines. Recently, the electromagnetic damper, which is composed of an electric motor, a ball screw, and a nut, was proposed. The electromagnetic damper has high responsiveness, controllability, and energy saving performance, and it has been reported they improved ride comfort and drivability. The electromagnetic damper has various function depending on the electric circuit connected to its electric motor and can be connected to each other more easily than that by hydraulic dampers. Therefore, the authors have focused on the connectivity of the electromagnetic damper, and have proposed to use electromagnetic damper for the coupled system, which enabled the characteristics of translational and rotational motion of a vehicle

Fukumori, Yuto, Hayashi, Ryuzo, Matsumi, Ryosuke, Suda, Yoshihiro, Nakano, Kimihiko

Submersible Pressure Transducer for Tank Fluid Level Monitoring

TBMG-1978906/01/2014

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).

Tactical Fighting System Simulator

TBMG-1982702/01/2014

Environmental Tectonics Corporation Southampton, PA 215-355-9100

Optical Device for Converting a Laser Beam Into Two Co-aligned but Oppositely Directed Beams

TBMG-1686307/01/2013

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.

Game-Based Training Applications Teach Soldiers Cultural Skills

TBMG-1572602/01/2013

Charles River Analytics released a case study of an effort for the US Army called CAATE (Culturally Aware Agents for Training Environments). Under this effort, Charles River developed tools to create game-based training applications for soldiers that teach them mission-critical social and cultural skills. Through computer games and by interacting with CAATE-based artificially intelligent agents, soldiers can safely train to effectively interact with residents of other countries and from different cultures.

Major Tokyo Train Station Slashes Energy Use With LED Technology

TBMG-1521911/01/2012

With the help of Panasonic LED and OLED lighting fixtures, the Japanese Ministry of the Environment is slashing overall energy use at a public station by 25 percent, with a 40-percent reduction in lighting energy alone. It’s all part of a pilot community development program called the Smart Station Project taking place at Jiyugaoka Station in Tokyo.

Acoustic Modelling and Characterization of Plate Heat Exchangers

2012-01-156206/13/2012

There is increased concern about the noise emission from cooling systems. This is mainly due to an increased need for cooling needs due to turbo-charging and EGR systems, which tend to increase the fan power and thereby the noise. An important issue in this context is the behavior of the heat-exchanger and its acoustic transmission and absorption properties. In this paper an acoustic model to evaluate such data for a common type of heat exchanger, the parallel plate type, is presented. The basic configuration is assumed to be a matrix of parallel, narrow channels. The developed model is based on a so called equivalent fluid for an anisotropic medium. It is mainly dependent on the heat exchanger geometry combined with the Kirchhoff model for thermo-viscous wave propagation in narrow tubes. The proposed model can be used to predict the sound transmission and absorption for an entire heat exchanger for incident plane waves. This model is validated by comparison with measurement results

Allam, Sabry, Åbom, Mats

Holographic Radar Pinpoints Rapid Shell Fire

TBMG-1284702/01/2012

Cambridge Consultants has successfully carried out trials tracking 5 inch shells travelling at over 1,000 miles per hour for the US Department of Defense (DoD). The groundbreaking radar developed specifically for this task was able to measure the trajectory and burst points of shells fired from a naval gun at a rate of one every three seconds — the first time radar has been used this way. The technology will eventually be used by the US DoD for training against attack by fast moving land and sea vehicles.

Mizzou Engineering Electric Car Club contributes to national safety effort

11MOMD1028_0311/01/2011

UNIVERSITY OF MISSOURI STUDENTS GATHER DATA FOR HYBRID AND ELECTRIC VEHICLE FIRST RESPONDER MATERIALS. STUDENTS JOINING THE UNIVERSITY of Missouri's Electric Car Club as an extracurricular activity never imagined they'd play a key role in a national agency's effort to educate emergency first responders to the intricacies of alternative fuel vehicles. But that opportunity for one of the newest within Mizzou's College of Engineering materialized when motive and means came to fruition under the American Recovery and Reinvestment Act. “A year-and-a-half ago, the National Fire Protection Association (NFPA) decided to develop and deliver a training curriculum for first responders to incidents involving electric and hybrid vehicles,” said John Cannon, project manager for training development at NFPA, headquartered near Boston. “Companies' technical manuals can be 25 to 30 pages long. They're not aimed at first responders.” First responders include fire services, emergency medical personnel

Wiese-Fales, Jan

Explosive Bolt Dual-Initiated From One Side

TBMG-1048407/01/2011

An explosive bolt has been developed that has a one-sided dual initiation train all the way down to the pyro charge for high reliability, while still allowing the other side of the bolt to remain in place after actuation to act as a thermal seal in an extremely high-temperature environment. This lightweight separation device separates at a single fracture plane, and has as much redundancy/reliability as possible. The initiation train comes into the explosive bolt from one side.

Collaborative Clustering for Sensor Networks

TBMG-1046307/01/2011

Traditionally, nodes in a sensor network simply collect data and then pass it on to a centralized node that archives, distributes, and possibly analyzes the data. However, analysis at the individual nodes could enable faster detection of anomalies or other interesting events, as well as faster responses such as sending out alerts or increasing the data collection rate. There is an additional opportunity for increased performance if individual nodes can communicate directly with their neighbors.

On-Highway Equipment Control and Communication Network

J1939/1_201105 (Historical)05/23/2011

SAE J1939-01 On-Highway Equipment Control and Communication Network specifies the minimum set of SAE J1939 documents that define the Truck and Bus Control and Communications Vehicle Network as it applies to on-highway equipment. Vehicles covered include all on-highway straight trucks and road trains. A road train consists of one towing vehicle (tractor) and one or more towed vehicles (trailers and dollies). Dolly axles within the road train are considered to be towed vehicles.

Truck Bus Control and Communications Network Committee

Ubisense

11OFHD0505_0805/05/2011

Vehicle Development Insights from Industry: Technologies and Trends for Future Growth - Watching your assets for competitive edge. The rail industry is entirely about motion: moving trains for the purpose of moving passengers. As we move about in our own lives we can do so blindly to a certain extent, remembering our way around our homes in the dark without switching the lights on. But any unfamiliar environment, or even slight changes in a very familiar one, causes us to need to see where things are to move about efficiently and safely. Sensing location is critical to efficient motion, particularly when the unexpected occurs. Location solutions are growing in popularity, especially among the transit community that is starting to embrace new technologies that provide a variety of efficiencies. For instance, GPS technology provides system-wide location of trains in real time, reducing accidents, delays, and costs while increasing track capacity and customer satisfaction. The new

Jennings, Adrian

'Mindshift' Biofeedback Gaming Technology

TBMG-874611/01/2010

The gamer's quest is for reality, but there are limits when an animated, armored man is shooting at a banshee flying at him at simulated warp speed on a video screen; or a caricature of an athlete is trying to hit a light that represents a ball that can curve in ways that defy physics.

A Comparison of a Semi-Active Inerter and a Semi-Active Suspension

2010-01-190310/05/2010

Inerters have become a hot topic in recent years, especially in vehicle, train, and building suspension systems. The performance of a passive inerter and a semi-active inerter was analyzed and compared with each other and it showed that the semi-active inerter has much better performance than the passive inerter, especially with the Hybrid control method. Eight different layouts of suspensions were analyzed with a quarter car model in this paper. The adaptation of dimensionless parameters was considered for a semi-active suspension and the semi-active inerters. The performance of the semi-active inerter suspensions with different layouts was compared with a semi-active suspension with a conventional parallel spring-damper arrangement. It shows a semi-active suspension, with more simple configuration and lower cost, has similar or better compromise between ride and handling than a semi-active inerter with the Hybrid control. A semi-active inerter performs its best with ‘Layout s6

Zhang, Xinjie, Ahmadian, Mehdi, Guo, Konghui

Roll your own

10OFHD1001_0410/01/2010

Technological advances into autonomously controlled vehicles facilitate road trains and troop support. Platooning of trucks and cars has been a long-sought-after goal of engineers who believe that the autonomous control of vehicles can save lives and fuel. While the technology of platooning or road trains is well known and studied, it has not transitioned beyond the test track because of the cost to install the necessary sensors and other infrastructure directly onto motorways. To surmount that problem, engineers are taking a different tack. Instead of focusing on the highway, engineers are now instead zeroing in on the vehicles. Some believe it to be a much more cost-effective solution that provides most of the desired benefits of platooning.

Rosenberg, Barry

SAE Off-Highway Engineering 2010-10-01

10OFHD100110/01/2010

A 'defensive' approach Oshkosh Corp. is providing executive leadership for this year's SAE Commercial Vehicle Engineering Congress, placing more emphasis on the military and defense businesses, and how those activities align with the commercial vehicle industry. Hybrid and mighty Having gained popularity un the automotive sector, many suppliers of hybrid drives are engineering their battery-electric offerings for the off-highway market. Customers, in turn, are experiencing major gains in efficiency and economy. Finding off-highway's top model Modeling, simulation advances help engineers get complex design to market quickly. Roll your own Technological advances into autonomously controlled vehicles facilitate road trains and troop support.

Offset Compound Gear Drive

TBMG-795305/01/2010

The Offset Compound Gear Drive is an in-line, discrete, two-speed device utilizing a special offset compound gear that has both an internal tooth configuration on the input end and external tooth configuration on the output end, thus allowing it to mesh in series, simultaneously, with both a smaller external tooth input gear and a larger internal tooth output gear. This unique geometry and offset axis permits the compound gear to mesh with the smaller diameter input gear and the larger diameter output gear, both of which are on the same central, or primary, centerline. This configuration results in a compact in-line reduction gear set consisting of fewer gears and bearings than a conventional planetary gear train. Switching between the two output ratios is accomplished through a main control clutch and sprag. Power flow to the above is transmitted through concentric power paths.

Method for Detecting Perlite Compaction in Large Cryogenic Tanks

TBMG-781604/01/2010

Perlite is the most typical insulating powder used to separate the inner and outer shells of cryogenic tanks. The inner tank holds the low-temperature commodity, while the outer shell is exposed to the ambient temperature. Perlite minimizes radiative energy transfer between the two tanks. Being a powder, perlite will settle over time, leading to the danger of transferring any loads from the inner shell to the outer shell. This can cause deformation of the outer shell, leading to damaged internal fittings.

Confidence-Based Feature Acquisition

TBMG-762403/01/2010

Confidence-based Feature Acquisition (CFA) is a novel, supervised learning method for acquiring missing feature values when there is missing data at both training (learning) and test (deployment) time. To train a machine learning classifier, data is encoded with a series of input features describing each item. In some applications, the training data may have missing values for some of the features, which can be acquired at a given cost. A relevant JPL example is that of the Mars rover exploration in which the features are obtained from a variety of different instruments, with different power consumption and integration time costs. The challenge is to decide which features will lead to increased classification performance and are therefore worth acquiring (paying the cost).

Quantification of Yard Hostler Activity and the Development of a Representative Yard Hostler Cycle

2009-01-265211/02/2009

Yard hostlers are tractors (switchers) used to move containers at ports and storage facilities. While many speed-time driving cycles for assessing emissions and performance from heavy-duty vehicles exist, a driving cycle representative of yard hostler activity at Port of Long Beach, CA was not available. Activity data were collected from in-use yard hostlers as they performed ship loading/unloading, rail loading/unloading and other yard routines, primarily moving containers on trailers or carts. The activity data were then used to develop four speed-time driving cycles with durations of 1200 seconds, representing light and heavy ship activities and light and heavy load rail activities. These cycles were constructed using actual speed-time data collected during activity logging and the cycles created were statistically comparable to each subset of activity data.

McKain, David L., Clark, Nigel, Atkinson, Richard J., Luzader, Zac J., Rutledge, Bradley

Active Learning With Irrelevant Examples

TBMG-631011/01/2009

An improved active learning method has been devised for training data classifiers. One example of a data classifier is the algorithm used by the United States Postal Service since the 1960s to recognize scans of handwritten digits for processing zip codes. Active learning algorithms enable rapid training with minimal investment of time on the part of human experts to provide training examples consisting of correctly classified (labeled) input data. They function by identifying which examples would be most profitable for a human expert to label. The goal is to maximize classifier accuracy while minimizing the number of examples the expert must label.

Active Learning With Irrelevant Examples

TBMG-TB-00631011/01/2009

Classification algorithms can be trained to recognize and reject irrelevant data. An improved active learning method has been devised for training data classifiers. One example of a data classifier is the algorithm used by the United States Postal Service since the 1960s to recognize scans of handwritten digits for processing zip codes. Active learning algorithms enable rapid training with minimal investment of time on the part of human experts to provide training examples consisting of correctly classified (labeled) input data. They function by identifying which examples would be most profitable for a human expert to label. The goal is to maximize classifier accuracy while minimizing the number of examples the expert must label.

Inferential Sensing Techniques to Enable Condition Based Maintenance

2009-01-291210/06/2009

Inferential sensing, as it relates to the equipment operator, can be viewed as human intuition [1]. The person operating the equipment can sense there is something wrong while their intuition tells them when and what needs troubleshooting and repair. Attempts have been made to implement this human intuition model to monitor a vehicle operation and detect abnormalities. In many approaches traditional sensors are added to the vehicle which increases cost, complexity, and another failure point. After years of developments and techniques, there are few highly reliable on-board systems that can duplicate the human intuition model since the specific failure cannot be directly measured but must be inferred from a variety of symptoms. This paper describes an engineering approach using Physics of Failure (PoF) for specific subsystems, developing the applicable fatigue models, and then collecting, monitoring, and manipulating the real-time on-vehicle data to complement the “operator intuition

Dabell, Brian, Gordon, David, Pompetzki, Mark

Aerial Deployment and Inflation System for Mars Helium Balloons

TBMG-542307/01/2009

A method is examined for safely deploying and inflating helium balloons for missions at Mars. The key for making it possible to deploy balloons that are light enough to be buoyant in the thin, Martian atmosphere is to mitigate the transient forces on the balloon that might tear it.

Wide-Range Temperature Sensors With High-Level Pulse Train Output

TBMG-TB-00539806/29/2009

Two types of temperature sensors have been developed for wide-range temperature applications. The two sensors measure temperature in the range of –190 to +200 °C and utilize a thin-film platinum RTD (resistance temperature detector) as the temperature-sensing element. Other parts used in the fabrication of these sensors include NPO (negative-positive-zero) type ceramic capacitors for timing, thermally-stable film or wire-wound resistors, and high-temperature circuit boards and solder.

Varying the Divergence of Multiple Parallel Laser Beams

TBMG-1138111/01/2008

A provision for controlled variation of the divergence of a laser beam or of multiple parallel laser beams has been incorporated into the design of a conceptual free-space optical-communication station from which the transmitted laser beam(s) would be launched via a telescope. The original purpose to be served by this provision was to enable optimization, under various atmospheric optical conditions, of the divergence of a laser beam or beams transmitted from a ground station to a spacecraft. Beyond the original purpose, the underlying design concept could be beneficial for terrestrial free-space laser communication, ranging, and scientific instrumentation applications in which there are requirements to vary the divergences of laser beams.

Varying the Divergence of Multiple Parallel Laser Beams

TBMG-339911/01/2008

Implementing a Digital Phasemeter in an FPGA

TBMG-TB-00318709/11/2008

Firmware for implementing a digital phasemeter within a field-programmable gate array (FPGA) has been devised. In the original application of this firmware, the phase that one seeks to measure is the difference between the phases of two nominally- equal-frequency heterodyne signals generated by two interferometers. In that application, zero-crossing detectors convert the heterodyne signals to trains of rectangular pulses (see figure), the two pulse trains are fed to a fringe counter (the major part of the phasemeter) controlled by a clock signal having a frequency greater than the heterodyne frequency, and the fringe counter computes a time-averaged estimate of the difference between the phases of the two pulse trains.

Delaying Trains of Short Light Pulses in WGM Resonators

TBMG-316009/01/2008

Suitably configured whispering-gallery-mode (WGM) optical resonators have been proposed as delay lines for trains of short light pulses. Until now, it has been common practice to implement an optical delay line as a coiled long optical fiber, which is bulky and tends to be noisy. An alternative has been to implement an optical delay line as a coupled-resonator optical waveguide (a chain of coupled optical resonators), which is compact but limits the width of the pulse spectrum to the width of an optical resonance and thereby places a lower limit on the duration of a pulse. In contrast, a delay line according to the proposal could be implemented as a single WGM resonator, and the pulses delayed by the resonator could be so short that their spectral widths could greatly exceed the spectral width of any single resonance.

Delaying Trains of Short Light Pulses in WGM Resonators

TBMG-1125909/01/2008

Suitably configured whispering-gallery-mode (WGM) optical resonators have been proposed as delay lines for trains of short light pulses. Until now, it has been common practice to implement an optical delay line as a coiled long optical fiber, which is bulky and tends to be noisy. An alternative has been to implement an optical delay line as a coupled-resonator optical wave-guide (a chain of coupled optical resonators), which is compact but limits the width of the pulse spectrum to the width of an optical resonance and thereby places a lower limit on the duration of a pulse. In contrast, a delay line according to the proposal could be implemented as a single WGM resonator, and the pulses delayed by the resonator could be so short that their spectral widths could greatly exceed the spectral width of any single resonance.

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