Browse Topic: Cartography

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Simulation-Driven Load Spectrum Prediction_ Virtual RLDA for Chassis and Suspension System2026-26-00951/16/2026
In the rapidly evolving and highly competitive automotive industry, manufacturers are under immense pressure to bring products to market quickly while meeting customer expectations. As a result, optimizing the product development timeline has become essential. Structural integrity analysis for chassis and suspension systems lies in the accurate acquisition of operational load spectra, conventionally executed through Road Load Data Acquisition (RLDA) on instrumented vehicles subjected to proving ground excitation. At this point, RLDA is mainly used for final validation and fine-tuning. If any performance shortfalls, such as premature component failure or durability issues, are discovered, they often trigger design revisions, prototype rework, and additional testing This study proposes a Virtual Road Load Data Acquisition (vRLDA) methodology employing a high-fidelity full-vehicle multibody dynamic (MBD) representation developed in Adams Car. The system is parameterized and uses high
Goli, Naga Aswani Kumar, PRASAD, TEJ PRATAP
Unique Optimization Approach of Axle Component and it’s Weld Life Improvement2024-26-03161/16/2024
Axles are a prominent part of automotive design. Along with a power transmission and differential system, axles support a vehicle’s weight and road-load reactions. Axles carry different attachments such as brakes and suspensions using brackets. Welds play an important role in design and longevity of bracket assemblies. Welds can be susceptible to fractures caused by intrusions akin to cracks and/or discontinuities, compounded by stress concentration due to weld profile and welding processes. Additionally, the simultaneous optimization of both brackets and welds remains a challenge with limited available methods. While topography or shape optimization techniques can enhance bracket robustness by minimizing compliance as the objective, this approach might inadvertently elevate the likelihood of weld fracture if weld dimensions are not concurrently updated. In this endeavor, compliance is used to improve weld life without affecting bracket robustness by using the Vertex Morphing
Wagh, Pranav, Sutar, Mohan, Nilangekar, Abhijit
Research on Automatic Joint Calibration Method of Multi 3D-LIDARs and Inertial Measurement Unit2021-01-00704/6/2021
In the field of automatic driving, the combination of 3D LIDAR and inertial measurement unit (IMU) is a common sensor configuration scheme in laser point-cloud localization, high-precision map making and point-cloud target detection. So it is critical to calibrate LIDAR and IMU accurately. At present, due to the large volume and high cost of 3D LIDAR with high-line-number(Such as 64 lines or 128 lines), the configuration scheme of using multiple low-line-number 3D LIDARs appears in the automatic driving vehicle sensing system. However, the common calibration methods are not suitable for multi 3D LIDARs and IMU parameters calibration on autonomous vehicle, which have the disadvantages of cumbersome implementation and low accuracy. In this paper, a joint calibration test platform composed of dual LIDARs and IMU is assembled, and a method of precise automatic calibration based on GPS/RTK data is proposed. Firstly, the initial parameters of the main 3D LIDAR and IMU are obtained by hand
Zhang, Jinghua, He, Rui, Wu, Jian, Li, Shuai, Chen, Xuesong, Du, Zhiqiang, Chen, Guosheng, Chen, Zhicheng
ONav and GeoPixel™ Web-Based Navigation for the Collection of Aerial ImageryTBMG-374708/1/2020
ONav is a heads-up navigation display for pilots for coastal imagery acquisition. The system is built on the Linux operating system (Debian) and utilizes a number of open-source tools and data sources.
Characterizing Richness of Previously Unmapped Terrain and its Impact on Navigation Using 3D Range SensorsTBMG-368425/1/2020
Landers to large planetary bodies such as Mars typically use a secondary reconnaissance spacecraft to generate high-fidelity 3D terrain maps that are subsequently used for landing site selection and creating onboard maps for terrain-relative navigation systems. This luxury does not exist with small primitive bodies such as comets and asteroids. For these bodies, the landing spacecraft has to perform the 3D mapping and, with possible help from ground control, choose a feasible landing site. To enable this operation, the spacecraft would need to carry a 3D ranging sensor system such as a LiDAR. With the spacecraft placed in extended mapping orbits, 3D range measurement data is then used to create a shape model of the object. Terrain-based navigation schemes that employ cameras could then be used to image, detect, match, and track features against the map database to provide a 6-degrees-of-freedom (DOF) navigation solution during descent. Camera-based systems, however, are not robust to
Real-Time Motion Classification of LiDAR Point Detection for Automated Vehicles2020-01-07034/14/2020
A Light Detection And Ranging (LiDAR) is now becoming an essential sensor for an autonomous vehicle. The LiDAR provides the surrounding environment information of the vehicle in the form of a point cloud. A decision-making system of the autonomous car is able to determine a safe and comfort maneuver by utilizing the detected LiDAR point cloud. The LiDAR points on the cloud are classified as dynamic or static class depending on the movement of the object being detected. If the movement class (dynamic or static) of detected points can be provided by LiDAR, the decision-making system is able to plan the appropriate motion of the autonomous vehicle according to the movement of the object. This paper proposes a real-time process to segment the motion states of LiDAR points. The basic principle of the classification algorithm is to classify the point-wise movement of a target point cloud through the other point clouds and sensor poses. First, a fixed size buffer store the LiDAR point clouds
Jo, Kichun, Kim, Chansoo, Cho, Sungjin, Sunwoo, Myoungho
Lidar Inertial Odometry and Mapping for Autonomous Vehicle in GPS-Denied Parking Lot2020-01-01034/14/2020
High-precision and real-time ego-motion estimation is vital for autonomous vehicle. There is a lot GPS-denied maneuver such as underground parking lot in urban areas. Therefore, the localization system relying solely on GPS cannot meets the requirements. Recently, lidar odometry and visual odometry have been introduced into localization systems to overcome the problem of missing GPS signals. Compared with visual odometry, lidar odometry is not susceptible to light, which is widely applied in weak-light environments. Besides, the autonomous parking is highly dependent on the geometric information around the vehicle, which makes building map of surroundings essential for autonomous vehicle. We propose a lidar inertial odometry and mapping. By sensor fusion, we compensate for the drawback of applying a single sensor, allowing the system to provide a more accurate estimate. Compared to other odometry using IMU and lidar, we apply a tight coupled of lidar and IMU method to achieve lower
Chen, Xuesong, Zhang, Sumin, Wu, Jian, He, Rui, Song, Shiping, Zhu, Bing, Zhao, Jian
Mobile Rugged Displays for Situational AwarenessTBMG-3528010/1/2019
With the constant emergence of new display technologies in the consumer sector, it is important for program managers and engineers in the military markets to be aware of how several of these advances can be incorporated into new military programs to achieve maximum benefit. Additionally, as older programs present themselves for technological refreshes, it is imperative to understand the difference in display specifications from previous decades and how updated technology provides avenues for their evolution and continued progress.
Bringing Human-Like Reasoning to Driverless Car NavigationTBMG-347727/1/2019
With the aim of bringing more human-like reasoning to autonomous vehicles, MIT researchers have created a system that uses only simple maps and visual data to enable driverless cars to navigate routes in new, complex environments.
Global Temperature Mapping and Crystallization Analysis of Supercooled Water Droplet Freezing Using Luminescent Imaging Technique2019-01-20096/10/2019
A prominent environmental phenomenon that greatly affects many industries including automotive, aeronautics, energy transmission, etc. is icing. One mechanism by which this occurs and plagues our machines and infrastructures that are exposed to the atmosphere is the icing of supercooled water droplets on a surface - either by impact against a surface or spontaneous nucleation and crystallization of a droplet at rest. The process by which nucleation propagates during the liquid-to-solid phase change and the thermodynamic implications in regards to latent heat generation and transfer are not fully understood on the single droplet scale. An attempt to better resolve these unknowns in both spatial and temporal domains has been made here. Previous efforts have implemented a unique temperature sensing technique utilizing luminescent dyes. A thermally sensitive luminescent paint coated onto the surface of interest allows direct mapping of the heat transfer from the supercooled liquid droplet
Patterson, Wesley Chad, Sakaue, Hirotaka
Driveline NVH Integration of An NA Truck Program2019-01-15596/5/2019
In the current automotive industry, it is common that the driveline subsystem and components are normally from different automotive suppliers for OEMs. In order to ensure proper system integration and successful development of driveline system NVH performances, collaboration efforts between OEMs and suppliers are very demanding and important. In this paper, a process is presented to achieve successfulness in developing and optimizing vehicle integration through effective teamwork between a driveline supplier and a major OEM. The development process includes multiple critical steps. They include target development and roll down, targets being specific and measurable, comprehension of interactions of driveline and vehicle dynamics, accurate definition of sensitivity, proper deployment of modal mapping strategy, which requires open data sharing; and system dynamics and optimization. More specially, the supplier can work with OEM to seek the most cost-effective solutions, through tuning
Peng, Ying, Shi, Zhenghong, Folts, Christopher, Kopp, Gregory, Sun, Zhaohui, Sandstrom, Alexander
Quantum Radio Aids Communications and MappingTBMG-341644/1/2019
GPS signals do not penetrate very deeply or at all in water, soil, or building walls, and therefore can’t be used by submarines or in underground activities such as surveying mines. GPS also may not work well indoors or even outdoors among city skyscrapers. For soldiers, radio signals may be blocked in environments cluttered by rubble or many interfering electromagnetic devices during military or disaster recovery missions.
Going DIGITAL & ELECTRIC @ bauma 201919TOFHP04_054/1/2019
Digitalization and electrification are dominant themes in the equipment and technology being revealed at this year's largest trade show for construction and mining. Digitalization, efficiency and sustainability are three megatrends that off-highway OEMs and suppliers will be touting this month at the triennial bauma trade fair in Munich, when they reveal their technology-laden machines and the intelligent systems that help make them smarter, cleaner and safer. Particular focal areas for many of these companies include electric mobility, telematics and networked construction sites, and increasingly autonomous operation. Some construction machines are already equipped with a range of sensors and communication interfaces that provide comprehensive data on aspects like job performance, location and fuel consumption. While entire fleets can be managed by telematics, many companies struggle with how to implement digital technologies and services.
Gehm, Ryan
Structural Integrity of In-Wheel Motors2018-01-18299/10/2018
In-wheel motors offer an optimized solution for novel drivetrain architectures of future electric vehicles that could penetrate into the mainstream automotive industry, moving the wheel actuation where it’s required, directly inside the wheels. Obtainable literature mainly deals with optimization of electromagnetically active parts, however, mechanical design of electromagnetically passive parts that indirectly influence motor performance also requires detailed analysis and extensive validation. To meet the optimal performance requirements (also durable) of an in-wheel traction motor, their mechanical design requires topology optimization of housing elements, thermal mapping, geometrical and dimensional tolerance checks and selection of proper hub bearings, in order to assure consistent electromagnetic behavior stability The following paper uniquely describes the review of loads acting on an in-wheel motor, the workflow of a typical mechanical design process, testing, and validation
Frajnkovic, Matic, Omerovic, Senad, Rozic, Uros, Kern, Jurij, Connes, Raphael, Rener, Kristof, Biček, Matej
Using Multiple Photographs and USGS LiDAR to Improve Photogrammetric Accuracy2018-01-05164/3/2018
The accident reconstruction community relies on photogrammetry for taking measurements from photographs. Camera matching, a close-range photogrammetry method, is a particularly useful tool for locating accident scene evidence after time has passed and the evidence is no longer physically visible. In this method, objects within the accident scene that have remained unchanged are used as a reference for locating evidence that is no longer physically available at the scene such as tire marks, gouge marks, and vehicle points of rest. Roadway lines, edges of pavement, sidewalks, signs, posts, buildings, and other structures are recognizable scene features that if unchanged between the time of accident and time of analysis are beneficial to the photogrammetric process. In instances where these scene features are limited or do not exist, achieving accurate photogrammetric solutions can be challenging. Off-road incidents, snow-covered roadways, rural areas, and unpaved roadways are examples
Terpstra, Toby, Dickinson, Jordan, Hashemian, Alireza
Aerospace & Defense Technology: October 201717AERP1010/1/2017
Using Thermal Simulation to Model the Effects of Wind on the Mars Curiosity Rover Quality and Validation of Digital Designs for Aerospace and Defense Scaling LiDAR Optical Payloads from Drones to Miniature UAVs Using Sintered Fiber Metal Composites for Aircraft Acoustic Attenuation GaN Breaks Barriers RF Power Amplifiers Go Wide and High Test System Ensures Flawless Performance of Military RF Devices The Impact of Video Compression on Remote Cardiac Pulse Measurement Using Imaging Photoplethysmography Remote physiological measurement technique leverages digital cameras to recover the blood volume pulse from the human body. Sensitivity Simulation of Compressed Sensing Based Electronic Warfare Receiver Using Orthogonal Matching Pursuit Algorithm Calculate the sensitivity of a CS based EW receiver using two modulation schemes. Initial Validation of Ballistic Shock Accelerometers A Test Operations Procedure (TOP) describing methods and instrumentation used in the initial validation of
High-Speed Network Protocol for Faster, More Reliable Emergency ResponseTBMG-272748/1/2017
Anew network protocol — the Multi Node Label Routing (MNLR) protocol — was developed to improve the information flow between emergency responders at the scene of an incident and decision-makers at the office of emergency management.
Network Geolocation TechnologyTBMG-272888/1/2017
A network geolocation technology (NGT) can be used to determine the physical location of a networked Internet user, as well as accurately determine if an Internet user is in fact in the metropolitan service area that the user claims as his/her location. NGT is based on the laws of physics, and operates independent of an IP address lookup or any other pre-existing user network address profiles.
Numerical Simulation and Experimental Validation of an Engine Oil Sump for Improved Noise Characteristics2017-01-18016/5/2017
Powertrain is the major source of noise and vibration in commercial vehicles and has significant contribution on both interior and exterior noise levels. It is vital to reduce the radiated noise from powertrain to meet customer expectations of vehicle comfort and to abide by the legislative noise requirements. Sound intensity mapping technique can identify the critical components of noise radiation from the powertrain. Sound intensity mapping has revealed that oil sump as one of the major contributors for radiated noise from powertrain. Accounting the effect of dynamic coupling of oil on the sump is crucial in predicting its noise radiation performance. Through numerical methods, some amount of work done in predicting the dynamic characteristics of structures filled with fluid. This paper discusses on the capability of numerical approach in predicting the oil sump modal characteristics with fluid-structure interaction and consequent verification with experimental modal test results
Sadasivam, Sivasankaran, Palsule, Aditya, Loganathan, Ekambaram, Inavolu, Nagasuresh, Medisetti, Jaganmohan Rao
An Efficient Input Mobility Mapping Computational Method2017-01-18066/5/2017
The input mobility is a crucial structural parameter regarding vibro-acoustic design of industrial objects. Whatever the frequency range, the vibrational power input into a structure -and consequently the average structural-acoustic response- is governed by the input mobility. When packaging structure-borne noise sources, the knowledge of the input mobility at the source connection points is mandatory for noise control. The input mobility is classically computed at the required points as a specific Frequency Response Function (FRF). During an industrial design process, the choice of connection points requires an a priori knowledge of the input mobility at every possible location of the studied structure-borne source, i.e. a mapping of the input mobility. The classical FRF computation at every Degree Of Freedom (DOF) of the considered structure would lead to consider millions of load cases which is beyond current computational limits. This paper presents how to efficiently compute the
Gagliardini, Laurent
Study on Methods of Coupling Numerical Simulation of Conjugate Heat Transfer and In-Cylinder Combustion Process in GDI Engine2017-01-05763/28/2017
Wall temperature in GDI engine is influenced by both water jacket and gas heat source. In turn, wall temperature affects evaporation and mixing characteristics of impingement spray as well as combustion process and emissions. Therefore, in order to accurately simulate combustion process, accurate wall temperature is essential, which can be obtained by conjugate heat transfer (CHT) and piston heat transfer (PHT) models based on mapping combustion results. This CHT model considers temporal interaction between solid parts and cooling water. This paper presents an integrated methodology to reliably predict in-cylinder combustion process and temperature field of a 2.0L GDI engine which includes engine head/block/gasket and water jacket components. A two-way coupling numerical procedure on the basis of this integrated methodology is as follows. With SAGE detailed chemical kinetics model, 3D CFD was applied to simulate the in-cylinder combustion and predict emissions with transient pressure
Wu, Minyue, Pei, Yiqiang, Qin, Jing, Li, Xiang, Zhou, Jianwei, Zhan, Zhang Song, Guo, Qi-yi, Liu, Bin, Hu, Tie Gang
Study of Active Steering Algorithm Logic in EPS Systems by Detecting Vehicle Driving Conditions2017-01-14813/28/2017
Conventional EPS (Electric Power Steering) systems are operated by one type of steering tuning map set by steering test drivers before being released to customers. That is, the steering efforts can't change in many different driving conditions such as road conditions (low mu, high mu and unpaved roads) or some specific driving conditions (sudden stopping, entering into EPS failure modes and full accelerating). Those conditions can't give drivers consistent steering efforts. This paper approached the new concept technology detecting those conditions by using vehicle and EPS sensors such as tire wheel speeds, vehicle speed, steering angle, steering torque, steering speed and so on. After detecting those conditions and judging what the best steering efforts for safe vehicle driving are, EPS systems automatically can be changed with the steering friction level and selection of steering optimized mapping on several conditions.
Lee, Kyung-bok, Lee, Sanghyuk, Kim, Namyoung, Kim, Bong Soo, Chi, Tae soo, Kim, Do young
Video Analysis of Motorcycle and Rider Dynamics During High-Side Falls2017-01-14133/28/2017
This paper investigates the dynamics of four motorcycle crashes that occurred on or near a curve (Edwards Corner) on a section of the Mulholland Highway called “The Snake.” This section of highway is located in the Santa Monica Mountains of California. All four accidents were captured on video and they each involved a high-side fall of the motorcycle and rider. This article reports a technical description and analysis of these videos in which the motion of the motorcycles and riders is quantified. To aid in the analysis, the authors mapped Edwards Corner using both a Sokkia total station and a Faro laser scanner. This mapping data enabled analysis of the videos to determine the initial speed of the motorcycles, to identify where in the curve particular rider actions occurred, to quantify the motion of the motorcycles and riders, and to characterize the roadway radius and superelevation throughout the curve. For each crash video, this paper reports quantitative data from the crash along
Rose, Nathan A., Carter, Neal, Pentecost, David, Hashemian, Alireza
Electric Drive Transient Behavior Modeling: Comparison of Steady State Map Based Offline Simulation and Hardware-in-the-Loop Testing2017-01-16053/28/2017
Electric drives, whether in battery electric vehicles (BEVs) or various other applications, are an important part of modern transportation. Traditionally, physics-based models based on steady-state mapping of electric drives have been used to evaluate their behavior under transient conditions. Hardware-in-the-Loop (HIL) testing seeks to provide a more accurate representation of a component’s behavior under transient load conditions that are more representative of real world conditions it will operate under, without requiring a full vehicle installation. Oak Ridge National Laboratory (ORNL) developed such a HIL test platform capable of subjecting electric drives to both conventional steady-state test procedures as well as transient experiments such as vehicle drive cycles. This facility was used to compare the behavior of an electric drive installed in a BEV with the two methods: offline simulation built from the experimental steady state efficiency map, and HIL experimentation of the
Chambon, Paul, Deter, Dean, Smith, David, Bauman, Grant
Aircraft Configured for Flight in an Atmosphere Having Low DensityTBMG-264993/1/2017
NASA Langley Research Center researchers have developed an airplane capable of being stowed in a confined volume and deployed in a high-altitude environment for extended-duration flight operations in a low-density atmosphere. Engineers, scientists, and end users can take advantage of this innovation that provides previously unattainable high-altitude flight operations. The airplane is delivered to a specified altitude folded in a container or rocket. Once released, the plane unfolds and executes a pull-up maneuver to stabilize altitude. In addition, the current suite of onboard scientific instrumentation includes magnetometers, a mass spectrometer, and variable-use cameras. NASA is seeking market insights on commercialization of the new airplane design, and welcomes interest from potential producers, users, and licensees.
Detection and Characterization of Recurring Slope LineaeTBMG-2605012/1/2016
Recurring Slope Lineae (RSL) are low-albedo features that appear and disappear seasonally on Martian slopes. They provide distinct surface markers that are thought to result from the activity of subsurface water. Reliable characterizations of RSL activity are needed to test this hypothesis. RSL are of high scientific interest, and could inform future mission planning priorities beyond sample return.
Method for Analytical Calculation of Harmonic Content of Auto-Transformer Rectifier Units2016-01-20599/20/2016
Auto transformer rectifier units (ATRUs) are commonly used in aircraft applications such as electric actuation for harmonic mitigation due to their high reliability and relative low cost. However, those components and the magnetic filter components associated to it are the major contributors to the overall size and weight of the system. Optimization of the magnetic components is essential in order to minimize weight and size, which are major market drivers in aerospace industry today. This requires knowledge of the harmonic content of the current. This can be obtained by simulation, but the process is slow. In order to enable fast and efficient design space exploration of optimal solutions, an algebraic calculation process is proposed in this paper for multi-pulse ATRUs (e.g. 12-pulse and 18-pulse rectifiers), starting from existing solution proposed for 6 pulse rectifier in the literature. The method consists of mapping AC and DC sides of a balanced 6N-Pulse system into the sum of
Loewenherz, Rolf, Valdivia-Guerrero, Virgilio, Diaz Lopez, Daniel, Parkin, Joshua
Methods of Real-Time Image Enhancement of Flash LIDAR Data and Navigating a Vehicle Using Flash LIDAR DataTBMG-251408/1/2016
NASA’s Langley Research Center has developed 3D imaging technologies (Flash LIDAR) for real-time terrain mapping and synthetic vision-based navigation. To take advantage of the information inherent in a sequence of 3D images acquired at video rates, NASA Langley has also developed an embedded image-processing algorithm that can simultaneously correct, enhance, and derive relative motion by processing this image sequence into a high-resolution 3D synthetic image. Traditional scanning LIDAR techniques generate an image frame by raster scanning an image one laser pulse per pixel at a time, whereas Flash LIDAR acquires an image much like an ordinary camera, generating an image using a single laser pulse. The benefits of the Flash LIDAR technique and the corresponding image-to-image processing enable autonomous vision-based guidance and control for robotic systems. The current algorithm offers up to eight times image resolution enhancement, as well as a 6-degree-of-freedom state vector of
Determining Position and Speed through Pixel Tracking and 2D Coordinate Transformation in a 3D Environment2016-01-14784/5/2016
This paper presents a methodology for determining the position and speed of objects such as vehicles, pedestrians, or cyclists that are visible in video footage captured with only one camera. Objects are tracked in the video footage based on the change in pixels that represent the object moving. Commercially available programs such as PFTracktm and Adobe After Effectstm contain automated pixel tracking features that record the position of the pixel, over time, two dimensionally using the video’s resolution as a Cartesian coordinate system. The coordinate data of the pixel over time can then be transformed to three dimensional data by ray tracing the pixel coordinates onto three dimensional geometry of the same scene that is visible in the video footage background. This paper explains the automated process of first tracking pixels in the video footage, and then remapping the 2D coordinates onto three dimensional geometry using previously published projection mapping and photogrammetry
Neale, William T., Hessel, David, Koch, Daniel
Numerical Study of Internal Combustion Engine using OpenFOAM®2016-01-13464/5/2016
We developed the numerical simulation tool by using OpenFOAM® and in-house simulation codes for Gasoline Direct Injection (GDI) engine in order to carry out the precise investigation of the throughout process from the internal nozzle flow to the fuel/air mixture in engines. For the piston/valve motions, a mapping approach is employed and implemented in this study. In the meantime, the spray atomization including the liquid-columnbreakup region and the secondary-breakup region are simulated by combining the different numerical approaches applied to each region. By connecting the result of liquid-column-breakup simulation to the secondary-breakup simulation, the regions which have different physical phenomena with different length scales are seamlessly jointed; i.e., the velocity and position of droplets predicted by the liquid-column-breakup simulation is used in the secondary breakup simulation so that the initial velocity and position of droplets are transferred. The simulation
Hosaka, Tomoyuki, Sugii, Taisuke, Ishii, Eiji, Oryoji, Kazuhiro, Sukegawa, Yoshihiro
Simulation of Atmospheric Turbulence for Wind-Tunnel Tests on Full-Scale Light-Duty Vehicles2016-01-15834/5/2016
During the past year, a novel turbulence generation system has been commissioned in the National Research Council (NRC) 9 m Wind Tunnel. This system, called the Road Turbulence System was developed to simulate with high fidelity the turbulence experienced by a heavy duty vehicle on the road at a geometrical scale of 30%. The turbulence characteristics that it can simulate were defined based on an extensive field measurement campaign on Canadian roads for various conditions (heavy and light traffic, topography, exposure) at heights above ground relevant not only for heavy duty vehicles but also for light duty vehicles. In an effort to improve continually the simulation of the road conditions for aerodynamic evaluations of ground vehicles, a study was carried out at NRC to define the applicability of the Road Turbulence System to aerodynamic testing of full-scale light duty vehicles. Using the on-road measurements as a guide, it was concluded that the RTS appears to provide a more
McAuliffe, Brian R., Wall, Alanna, Larose, Guy
Fabrication of an Integrated Photonic Waveguide Joint in Micromachined SiliconTBMG-242554/1/2016
High-aspect-ratio silicon structures are necessary components in many MEMS (microelectromechanical systems). Aspect ratio is defined as the ratio of the height of the structure to its lateral width. The structures are typically fabricated through bulk micromachining steps such as deep reactive ion etching. In some cases, multiple levels of high-aspect-ratio structures are required. For instance, one may want to etch completely through a silicon wafer to thermally isolate a bolometer or provide waveguide coupling to an antenna defined on an insulating membrane, and at the same time have integrated high-topology structures required for microwave coupling or filtering. Definition of the structures typically uses photolithographic technology. But for high-aspect-ratio structures, spin cast resist becomes difficult to incorporate due to the non-uniform thickness of the resist around tall structures. One can cast very thick layers of photoresist, but this limits the minimum feature size, and
A 16-Beam, Non-Scanning, Swath-Mapping Laser Altimeter InstrumentTBMG-2327911/1/2015
The purpose of this work was to develop and demonstrate technologies for a next-generation, efficient, swath-mapping space laser altimeter. The Lidar Surface Topography (LIST) mission concept allows simultaneous measurements of 5-meter-spatial-resolution topography and vegetation vertical structure with decimeter vertical precision in an elevationimaging swath several kilometers wide from a 400-km-altitude Earth orbit. To advance and demonstrate needed technologies for the LIST mission, the Airborne LIST Simulator (ALISTS) pathfinder instrument was developed. ALISTS is a micropulse, single photon-sensitive waveform recording system based on a new and highly efficient laser measurement approach utilizing emerging laser transmitter and detector technologies.
NASA Vision Workbench (VWB) v3TBMG-223937/1/2015
VWB is a modular, extensible computer vision framework that supports tasks including automated science and engineering analysis, large satellite image processing, and 2D/3D environment reconstruction. The framework provides a rapid C++ development environment as well as a flexible, multi-platform system to deploy computer vision applications. The module interface allows new capabilities to be rapidly integrated, and a dataflow architecture allows image processing pipelines to be quickly developed and reconfigured.
Ice Shape Mapping by Means of 4D-Scans2015-01-21516/15/2015
When studying ice accretion processes experimentally it is desirable to document the generated ice shapes as accurately as possible. The obtained set of data can then be used for aerodynamic studies, the improvement of icing test facilities, the development of design criteria, the validation of ice accretion simulation tools as well as other applications. In the past, various ice shape documentation methods have been established including photography, cross-sectional tracing, molding and casting as well as 3D-scanning. This work introduces a new ice shape documentation technique based on active 3D-scanning in combination with fluorescent dyes and an optimized set of optical filters. The new approach allows recording the time-resolved three dimensional growth of an arbitrary ice shape. Based on this concept a so-called 4D-scanning system is developed, which allows a detailed evaluation of icing experiments and hence a better understanding of the ice accretion process itself. The
Puffing, Reinhard F.A., Hassler, Wolfgang, Tramposch, Andreas, Peciar, Marian
Unsteady Thermal Simulations of Wing Ice Protection Systems Integrated in Metallic or Composite Structures2015-01-20936/15/2015
Advanced sizing of the thermal wing ice protection system (WIPS) requires an improved and a robust manner to simulate the system operation in unsteady phases and particularly in de-icing operations. A two dimensional numerical tool has been developed to enable the simulation of unsteady anti-icing and de-icing operations. For example, the WIPS may be activated with delay after entering into the icing conditions. In this case, ice starts to accrete on the leading edge before the WIPS heats up the skin. Another example is the ground activation of the WIPS for several seconds to check its functionality: low external cooling may cause high thermal constraints that must be estimated with accuracy to avoid adverse effects on the structure. Thermal de-icing WIPS integrated in composite structures intrinsically have unsteady behaviors; the tool enables the computation of the skin temperature evolution with the time. This provides an insightful indication on the de-icing performance of the WIPS
Henno, Maxime
Effective Placement of Noise Control Acoustic Material in a Vehicle for a Typical Front of Dash Application by Identifying Critical Location Area through Effective Sound Intensity Mapping Method2015-01-22516/15/2015
NVH in automobile has been very demanding over the years and is considered to be one of the key focus areas for customer satisfaction identified by the automobile companies. A lot of work has been done towards optimizing noise treatment materials and its effective placement to suit performance, weight and cost. This paper outlines a unique method to optimize the coverage of the NCT around the FOD area by conducting an effective sound intensity mapping around the FOD area at the cabin side with the help of a two microphone based sound intensity probe.
Varghese, Alex, Palled, Satish
Active Control of Structure-Borne Road Noise Based on the Separation of Front and Rear Structural Road Noise Related Dynamics2015-01-22226/15/2015
Axle forces from tire-road interaction can excite different structural resonances of the vehicle hence a high number of sensors is required for observing and separating all the vibrations dynamics that are coherent with the cabin noise. Feed-forward road noise control strategies adopted so far rely mainly on capturing these dynamics and thus the number of sensors constitutes one major limitation of this approach. Therefore there is a necessity for reducing the number of sensors without degrading the performance of an ANC system. In the past coherence function analysis has been found to be a useful tool for optimizing the sensor location. In this case coherence function mapping was performed between an array of vibration sensors and the headrest microphones in order to identify the locations on the structure that are highly correlated with road noise bands in the compartment. A vehicle with an advanced suspension system was used for applying the method and defining some locations as
Zafeiropoulos, Nikos, Ballatore, Marco, Moorhouse, Andy, Mackay, Andy
Neo-Geography Toolkit (NGT) v2TBMG-221766/1/2015
The Neo-Geography Toolkit (NGT) is a collection of open-source software tools for the automated processing of geospatial data, including images and maps. It can process raw raster data from remote sensing instruments and transform it into useful cartographic products such as visible image base maps, topographic models, etc. It can also perform data processing on extremely large geospatial data sets (up to several tens of terabytes) via parallel processing pipelines. Finally, it can transform raw metadata, vector data, and geo-tagged datasets into standard Neo-Geography data formats such as KML.
A Discussion on Vehicle AC System TXV Optimization2015-01-03644/14/2015
This paper presents the way to optimize vehicle AC system TXV to meet the various AC system requirements. It discusses vehicle AC system TXV sizing and selection process. In today's automotive industry, sizing and selecting the TXV is more complicated than before as various new components are introduced such as external control compressor, internal control compressors and internal heat exchanger etc. These components complicated the system interaction among the components. Thus it requires mapping TXV characteristic to meet the system demand. Sizing TXV capacity, it must start with the vehicle heat load requirement. The type of TXV (i.e. cross charge or parallel charge head) is determined by the system configuration such as compressor, evaporator, and condenser type and with or without internal heat exchanger, etc. To optimize TXV in the system involves in evaluating TXV characteristic and cooling capacity in the various AC operating conditions. The criteria for the evaluation can
Zheng, Yinhua
Recent Developments in X-ray Diagnostics for Cavitation2015-01-09184/14/2015
Cavitation plays an important role in fuel injection systems. It alters the nozzle's internal flow structure and discharge coefficient, and also contributes to injector wear. Quantitatively measuring and mapping the cavitation vapor distribution in a fuel injector is difficult, as cavitation occurs on very short time and length scales. Optical measurements of transparent model nozzles can indicate the morphology of large-scale cavitation, but are generally limited by the substantial amount of scattering that occurs between vapor and liquid phases. These limitations can be overcome with x-ray diagnostics, as x-rays refract, scatter and absorb much more weakly from phase interfaces. Here, we present an overview of some recent developments in quantitative x-ray diagnostics for cavitating flows. Measurements were conducted at the Advanced Photon Source at Argonne National Laboratory, using a submerged plastic test nozzle. X-ray radiography provides quantitative line-of-sight density
Duke, Daniel, Swantek, Andrew, Kastengren, Alan, Fezzaa, Kamel, Powell, Christopher
Electronic Warfare TechnologyTBMG-218814/1/2015
Military electronic warfare (EW) systems including navigation, radar guidance, terrain mapping and others, require lightweight compact components, with radio frequency (RF) output power levels to several kilowatts typically needed to meet system requirements. As GaN transistor technology advances in frequency and power output, solid state power amplifiers (SSPAs) have begun replacing traveling wave tubes (TWTs) at frequencies up to 6 GHz. The utilization of this technology results in a lower cost and greater efficiency over the life of a product.
Instant Mileage Assistance (IMA) in a Geared Two Wheeler2014-32-002811/11/2014
The Instant Mileage Assistance (IMA), as the name indicates, is a system to guide the vehicle users to realize maximum fuel economy (mileage). This system is targeted to provide users with instantaneous mileage indication depending on the current driving pattern, correct gear operating zone (in case of a geared vehicle) through gear up/down shift assist indication and the accurate distance the vehicle can travel before the fuel tank is empty, thereby assisting the user in harnessing maximum fuel economy the vehicle can deliver and also safely reach the next refilling station. The instantaneous mileage is calculated by mapping the distance travelled by the vehicle and the respective amount of fuel consumed, during a particular period of time, and is displayed using an instrument cluster. When the fuel level in the tank reaches a known threshold, the distance to empty is in turn calculated from the instantaneous mileage value hence providing a more accurate and realistic indication to
Manikandan, T, Ameer, S Sarmadh, Sivakumar, A, Kumar, Davinder, Venkatesan, R, Kumar, VenkataKalyana
Evaluation of Camshaft Control Strategies for a GDI Engine using a Multidisciplinary Optimisation Framework2014-01-258110/13/2014
This paper presents a calibration optimization study for a Gasoline Direct Injection engine based on a multidisciplinary design optimization (MDO) framework. The paper presents the experimental framework used for the GDI engine mapping, followed by an analysis of the calibration optimization problem. The merits of the MDO approach to calibration optimization are discussed in comparison with a conventional two-stage approach based on local trade-off optimization analysis, focused on a representative emissions drive cycle (NEDC) and limited part load engine operation. The benefits from using the MDO optimisation framework are further illustrated with a study of relative effectiveness of different camshaft timing control strategies (twin independent Versus fixed timing, exhaust only, inlet only and fixed overlap / dual equal) for the reference GDI engine based on the part load test data. The main conclusion is that the MDO structure offers an effective framework for the GDI steady state
Kianifar, Mohammed Reza, Campean, Felician, Richardson, David
Military Technologies for Improving Efficiency & Safety in Off-Road Commercial Vehicles2014-01-23989/30/2014
Off-road commercial vehicles many times have to work at remote areas in poor working conditions like reduced visibility due to fog, snow, inadequate ambient lighting, dust etc. They may not have any access to emergency facilities in such places. Challenging geographical terrains and adverse weather conditions makes the situation worse. The combination of both can further degrade working conditions. The operator may need to either work or guide his vehicle through tight places or in hilly areas having such conditions. That imposes many challenges to operator in terms of efficiency & safety of both operator & vehicle. In an effort to increase productivity and efficiency operator may miss to look at safety aspects consequently, leading to accidents that can incur heavy losses due to damages to vehicle further delaying the work. It can even lead to a life threatening emergency in some cases. On the other hand, decrease in efficiency results in increased cost of operation due to unnecessary
Pawar, Sanket
Friction Coefficient Mapping during Brake Interventions2014-01-24969/28/2014
This paper comprises obtaining friction coefficient (μ) measure by extracting surface and texture information using sensors during brake interventions. A primary estimate of friction coefficient has been obtained using wheel and vehicle signals. The estimates have been compared and combined to obtain a more accurate measure of friction coefficient. Finally, a suitable interpolation technique is used to obtain a μ-grid around the vehicle. The grid is graphically realized with the aid of visualization techniques using vehicle traces. This type of surface characterization usually enables brake distance optimization and effective countermeasures pertaining to a standard ESP system.
Venkata Padmanabhan, Adarsh, Ravichandran, Hariram, Pappala, Lokendra Pavan Kumar, Shenoy, Shreyas
Structures Perspective for Strength and Fatigue Prognosis in CompositesF-0070-2014-96365/20/2014
Recent advances in understanding deformation and failure mechanisms of polymer-matrix composites used in rotor structures enable accurate and efficient measurement of material stiffness, strength, and fatigue characteristics based on testing small unidirectional laminate specimens. Successful failure predictions increased our confidence in the development of virtual test methods replacing some of the standard tests of multi-directional laminated composite materials with three-dimensional models accurately predicting deformation, damage topography, strength, and cycles to failure. However, the remaining key questions are related to the ability of transitioning the material scale virtual test information to larger composite structures. This work presents results of the feasibility assessment targeting the scaling of knowledge and methods acquired at the material scale, to larger structural elements.
Nikishkov, Yuri, Seon, Guillaume, Makeev, Andrew
LES of Flow Processes in an SI Engine Using Two Approaches: OpenFoam and PsiPhi2014-01-11214/1/2014
In this study two different simulation approaches to large eddy simulation of spark-ignition engines are compared. Additionally, some of the simulation results are compared to experimentally obtained in-cylinder velocity measurements. The first approach applies unstructured grids with an automated meshing procedure, using OpenFoam and Lib-ICE with a mapping approach. The second approach applies the efficient in-house code PsiPhi on equidistant, Cartesian grids, representing walls by immersed boundaries, where the moving piston and valves are described as topologically connected groups of Lagrangian particles. In the experiments, two-dimensional two-component particle image velocimetry is applied in the central tumble plane of the cylinder of an optically accessible engine. Good agreement between numerical results and experiment are obtained by both approaches.
Nguyen, Thuong, Janas, Peter, Lucchini, Tommaso, D'Errico, Gianluca, Kaiser, Sebastian, Kempf, Andreas
Study on Optimization for LNT+SCR System of Diesel Vehicle to Comply with the LEV3 Regulations2014-01-15294/1/2014
This paper describes how to meet LEVII ULEV70 emission standards and minimize fuel consumption with the combined NOx after-treatment (LNT+SCR) system for diesel vehicles. Through analysis of LNT's functionality and characteristics in a LNT+SCR combined after-treatment system, allowed a new control strategy to be established, different from the existing LNT-only system. In the 200°C or higher condition where SCR can provide the most stable NOx conversion efficiency, rich regeneration of LNT was optimized to minimize LNT deterioration and fuel consumption. Optimized mapping between rapid heat up strategy and raw NOx reduction maximized LNT's NOx conversion efficiency during the intervals when it is not possible for SCR to purify NOx This study used bench aged catalysts which were equivalent to 150K full useful life. During the Highway (HFET) driving cycle when the SCR conversion rate is generally high, fuel economy was improved by minimization DeNOx in LNT and improvement of the engine
Jeon, Jongik, Seo, Hyongman, Lee, Kangwon, Kwon, Soonhyung, Bae, Kisong
Integration of an E85 Reforming System into a Vehicle-Ready Package and Project Results2014-01-11914/1/2014
Ethanol can be converted into a 1:1:1 mixture of H2, CO, and CH4 at 300°C using a copper-nickel catalyst, a process known as “low-temperature ethanol reforming.” The hydrogen content of this mixture enables an engine to operate lean or with high levels of EGR, improving fuel economy and emissions. An onboard ethanol reformer- a catalyst module providing heat exchange with exhaust-was recently reported and shown to exhibit stable high conversion of ethanol driven by exhaust heat. This paper describes the successful integration and operation of a Ford 3.5L 3 TiVCT flex-fuel engine with a compact reformer and auxiliary hardware, fueled by E85. The system constitutes an integrated power system suitable for vehicle integration. The engine was operated on a mixture of E85 and reformate using a stoichiometric air-fuel ratio with internal EGR at a 12:1 compression ratio. At the worldwide mapping point, 1500 rpm/2.6 bar BMEP, use of 25% reformate in the fuel enabled stable engine operation with
Fowler, John, Morgenstern, David, Sall, Erik, Veinbergs, Martin E.
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