Browse Topic: Vehicle front ends

Items (333)

4/28/2020

This SAE Aerospace Standard (AS) covers air data computer equipment (hereinafter designated the computer) which when connected to sources of aircraft electrical power, static pressure, total pressure, outside air temperature, and others specified by the manufacturer (singly or in combination) provides some or all of the following computed air data output signals (in analog and/or digital form) which may supply primary and/or standby flight instruments: Pressure Altitude Pressure Altitude, Baro-Corrected Vertical Speed Calibrated Airspeed Mach Number Maximum Allowable Airspeed Over-speed Warning Total Air Temperature

A-4 Air Data Subcommittee

A Design and Optimization Method for Pedestrian Lower Extremity Injury Analysis with the aPLI Model

2020-01-09294/14/2020

As pedestrian protection tests and evaluations have been officially incorporated into new C-NCAP, more stringent requirements have been placed on pedestrian protection performance. In this study, in order to reduce the injury of the vehicle front end structure to the pedestrian's lower extremity during the collision, the advanced pedestrian legform impactor (aPLI) model was used in conjunction with the finite element vehicle model for collision simulation based on the new C-NCAP legform test evaluation regulation. This paper selected the key components which have significant influences on the pedestrian's leg protection performance based on the CAE vehicle model, including front bumper, front-cover plate, upper impact pillar, impact beam and lower support plate, to form a simplified model and conducted parametric modeling based on it. Then, the variable correlation analysis was carried out on the sample results obtained from the design of experiment (DOE), and the contribution analysis of design variables to the injury measures was discussed. The sample variables and responses were also used to construct the approximate models for further optimization studies. Taking the pedestrian lower extremity injuries as the optimization target, the front end structural parameters were matched and optimized. Finally, an optimal configuration for parameter matching of key components of the front end structure for pedestrian protection was established, which effectively improve the protection of pedestrian lower extremity.

Fu, Yue, Xu, Huijie, Lin, Guan, Zhan, Zhenfei, Wang, Ping, Chen, Ruyi, Yu, Huili

Using Vehicle EDR Data to Calculate Motorcycle Delta-V in Motorcycle-Vehicle Lateral Front End Impacts

2020-01-08854/14/2020

This research focuses on the use of Event Data Recorders (EDR) to assist in calculating speed loss or ΔV undergone by a motorcycle in a broadside type impact into a vehicle. If the struck vehicle has EDR data, this could be a useful tool in calculating motorcycle ΔV or corroborating motorcycle ΔV calculations from crush or other methodologies. Certain parameters critical to calculation of motorcycle ΔV must be considered, including the appropriate effective mass to use for the motorcycle/rider combination. This study used crash test data to determine a method of applying parameter values to accurately calculate motorcycle ΔV in a motorcycle-vehicle collision. In this study, three crash tests were performed in which a motorcycle with a dummy rider traveling in the range of 42 to 51 mph collided into the right front corner of a vehicle traveling between 5 and 16 mph. In all three tests, both the vehicle and motorcycle were instrumented with triaxial accelerometers and triaxial rate gyros. The first test involved a 2002 Kawasaki ZRX1200R traveling at 42.2 mph into the right front corner of a 2009 Chevrolet Malibu traveling at 5 mph. The impact occurred just forward of the vehicle’s right front wheel area. The second test involved a 2006 Yamaha YZF-R6 traveling at 48.1 mph into the right front corner of a 2012 Ford Focus traveling at 14 mph. The impact occurred near the vehicle’s right front headlight/bumper reinforcement area. The third test involved a 2013 Kawasaki Ninja EX300 traveling at 50.5 mph into the right front corner of a 2015 Nissan Sentra traveling at 9 mph. Again, the impact occurred near the vehicle’s right front headlight/bumper reinforcement area. In all the tests, the vehicle ACM-recorded data underreported the longitudinal ΔV in the range of 0.8-1.3 mph. Additionally, in all tests the vehicle ACM-recorded data overreported the lateral ΔV by 0.4-0.5 mph. This overreporting was present after adjustments were made for the ACM location. Overall, the EDR data was able to predict the motorcycle ΔV within a range of -5.9 mph to +3.1 mph. The underpredicted values were calculated with full rider and motorcycle weight, and the overpredicted values were calculated with half the rider weight.

Fatzinger, Edward, Landerville, Jon

Case Study on the Challenges and Responses of a Large Turnkey Assembly Line for the C919 Wing

2020-01-00103/10/2020

Design and production of an assembly system for a major aircraft component is a complex undertaking, which demands a large-scale system view. Electroimpact has completed a turnkey assembly line for producing the wing, flap, and aileron structures for the COMAC C919 aircraft in Xi’an, China. The project scope includes assembly process design, material handling design, equipment design, manufacture, installation, and first article production support. Inputs to the assembly line are individual component parts and small subassemblies. The assembly line output is a structurally completed set of wing box, flaps, and ailerons, for delivery to the Final Assembly Line in Shanghai. There is a trend toward defining an assembly line procurement contract by production capacity, versus a list of components, which implies that an equipment supplier must become an owner of production processes. The most significant challenge faced was the amount of front end engineering work required to develop detailed assembly processes and reconcile them with the customer, who remains the actual process owner. Other challenges include aircraft maturity delays, design changes due to process definition evolution, factory environmental conditions such as dust and varying temperature gradients, and cultural and communication challenges both internal and external. The result achieved by Electroimpact is an assembly line system composed of an integration of assembly tooling, special process equipment, NC machine equipment, inspection equipment, material handling and logistics equipment: Two robotic drilling cells integrated with both stationary and mobile tooling. Integrated wing major assembly cell with manual assembly jigs and large CNC wing drilling machines. Twenty-three other manual work stations. New technology developments implemented include: A new high-curvature nosepiece on the robot end effecter to enable accurate drilling and countersinking on the LE Spar D-Nose section. A new application and delivery system for single-sided temporary fasteners for wing panel drilling. Tooling design to accommodate large temperature variations.

Forbes, Mark

CONNECTORS, RECEPTACLE, ELECTRICAL, BOX MOUNTING, SOLDER CONTACT, HERMETIC, AN TYPE

AS31421A (Current)2/14/2020

AE-8C1 Connectors Committee

Finite Element Modeling of an Energy-Absorbing Guardrail End Terminal

02-12-04-00212/7/2020

Guardrail end terminals are specifically designed to decelerate vehicles during impact and protect vehicle occupants from severe injuries. The main objective of this research was to develop and validate a Finite Element (FE) model of the ET-Plus, a commonly used energy-absorbing guardrail end terminal. The ET-Plus FE model was created based on publicly available data on ET-Plus dimensions and material properties. The model was validated against the NCHRP-350 crash tests 27-30 and 31-30 by performing crash simulations with a vehicle model at 100 km/h (62 mph) pre-impact velocity. To check the model robustness, crash simulations with vehicle pre-impact velocities from 97 km/h (60 mph) to 113 km/h (70 mph) were also performed. The developed ET-Plus FE model has a high-quality mesh and can replicate the energy-absorbing mechanism. The time histories of the vehicle yaw angle predicted in the FE simulations of the two NCHRP 350 crash tests showed good agreement with the corresponding test data. Additionally, the model was stable in crash simulations with the investigated range of pre-impact velocities, and both post-impact velocities and peak acceleration showed increasing trends with increasing impact velocities. This model could be used by safety researchers to investigate the performance of the ET-Plus end terminal in various crash scenarios and to investigate various possible design improvements of the end terminal and/or the front end of new vehicles.

Meng, Yunzhu, Hu, Wen, Untaroiu, Costin Daniel

Modeling and Validation for the Hysteretic Behavior of an Automatic Belt Tensioner

2019-01-15466/5/2019

An automatic tensioner used in an engine front end accessory drive system (EFEADS) is taken as a study example in this paper. The working torque of the tensioner, which consists of the spring torque caused by a torsional spring and the frictional torques caused by the contact pairs, is analyzed by a mathematic analysis method and a finite element method. And the calculation and simulation are validated by a torque measurement versus angular displacement of a tensioner arm. The working torques of the tensioner under a loading and an unloading process are described by a bilinear hysteretic model, and are written as a function with a damping ratio. The rule of the action for the damping devices is investigated based on the simulation and a durability test of the tensioner. A finite element method for the tensioner without damping device is established. Then the radial deformation for the torsional spring under an unconstrained state is obtained. The analysis results have a good correlation with the measurements. The method presented in this paper is beneficial for predicting the working torque performance of an automatic tensioner, and reducing the design period and the cost for prototype validation.

Long, Shangbin, Zhao, Xuezhi, Xu, Pu, Shangguan, Wen-Bin

EDITORIAL: The unforgettable pyramid on the hood

19AUTP06_086/1/2019

If you're old enough to remember 1990, you may recall the best television ad of the year. It showed the front end of the all-new Lexus LS400 sedan against a black background. A multi-level pyramid of champagne glasses glistened in the center of the car's hood. It was demonstration time, and the demo was all about Noise, Vibration and Harshness-and the lack of it.

Brooke, Lindsay

Vertical Lift Aircraft Design through the Georgia Tech Integrated Product and Process Development Approach For Over the Past 30 Years

F-0075-2019-14732

5/13/2019

If you have considerable experience from industry and government in developing complex systems, one thing nice about being a Professor at a leading technical university is being able to help implement improvements in the education and development of complex systems, especially Vertical Lift Aircraft (VLA) systems. This is particularly true if you have the opportunity to participate as a member of major national efforts to implement improvements; as well as if you have the opportunity to serve on independent "red teams" reviewing industry proposals for complex system development. Fortunately, I have had these opportunities in my 35 years as the rotorcraft design professor in the School of Aerospace Engineering, Georgia Tech and as the Director for the Georgia Tech national Vertical Lift Research Center of Excellence (VLRCOE) for the past 33 years. The particular area I have pursued is development and implementation of an Integrated Product and Process Development (IPPD) methodology that has evolved from the Quality Engineering Revolution of the early 1990s. This IPPD methodology has served as the basis for the Georgia Tech Graduate Program in Aerospace Systems Design, which has become the largest of its kind in the world. It also has served as a research foundation area for a number of PhD student theses. It has also been used to support major DoD initiatives, such as the Concept Development and System Engineering Phase for the Army's Future Combat Systems, the Air Force-Navy Joint Advanced Strike Technology (JAST) Independent Assessment and the front end decision process for the Army's Future Vertical Lift (FVL) Program. A wake up call for the use of IPPD was given in the author's 1999 AHS Nikolsky Lecture (Ref.1), although I don’t believe that the VLA government and industry have really responded. This paper will start with an overview of the Quality Engineering Revolution and the emphasis on use of IPPD and Integrated Product Teams (IPTs). Some examples of IPPD use at Georgia Tech for aircraft design and on major programs will then be provided. It will end with another call for its use on forthcoming VLA programs.

Schrage, Daniel, Patel, Srujal

Nissan concept sport sedan is all-electric, driver-optional

19AUTP03_123/1/2019

Nissan looks to pump up the fun factor with the IMs, an all-electric sports sedan concept with autonomous driving capability. The car made its global debut at the 2019 North American International Auto Show. “While still being a driver's car, this concept lives within our very graspable future of creating/engineering a thrilling autonomous ride, bringing the car into the realm of ‘entertainment’, Giovanny Arroba, Nissan's program design director, told Automotive Engineering. IMs features dual electric motors in the front and the rear with an estimated 483 hp (360 kW) and 590 lb·ft (800 N·m) for all wheel drive capability. The 115 kWh battery pack, packaged under the floor, provides an estimated 380-mi (611.5-km) driving range. The sedan's dedicated EV platform essentially mirrors that of Nissan's IMx KURO electric crossover concept that debuted at the Tokyo Motor Show in 2017.

Buchholz, Kami

Flexible, Spinning Heat Shield for Spacecraft

TBMG-339123/1/2019

Heat shields are essentially used as the brakes to stop spacecraft from burning up and crashing on entry and reentry into a planet's atmosphere. Current spacecraft heat shield methods include huge inflatables and mechanically deployed structures that are often heavy and complicated to use.

A Robust Waveguide Millimeter-Wave Noise Source

TBMG-3323911/1/2018

A noise source is an enabling technology for passive millimeter-wave remote sensing applications such as atmospheric sounding, and precipitation and ice cloud measurements. NASA Goddard Space Flight Center has developed a packaged noise source that will allow calibration of the front end at the sensing frequency. This capability will eliminate or reduce the requirement of a clear view to cold space, which will reduce the mass and complexity as well as the total cost of the system.

Tech Briefs: August 2018

18AERP088/1/2018

Designing a High-Speed Decoy Unmanned Aerial Vehicle (UAV) Using Thermoplastics in Aerospace Applications In-Flight Real-Time Avionics Adaptation Using Turbine Flow Meters for Aerospace Test and Measurement Applications Communicating from Space: The Front End of Multiscale Modeling Laser-Based System Could Expand Space-to-Ground Communication Hydraulic Testing of Polymer Matrix Composite 102mm Tube Section Research could lead to development of a composite material that can be processed at a low temperature and still be used at 1000°F. Permeation Tests on Polypropylene Fiber Materials Study attempts to determine if polypropylene nanofiber materials can be used in air filtration systems to remove toxic vapors. Inter-Laboratory Combat Helmet Blunt Impact Test Method Comparison Ensuring consistent test methods could reduce the risk of head injuries.

New Pulse Analysis Techniques for Radar and EW

TBMG-290906/1/2018

Truck and Sport Utility Vehicle Front End Stiffness Corridors

2018-01-05184/3/2018

The purpose of this study was to characterize front stiffness response of contemporary sport utility vehicles (SUVs) and trucks. Vehicle front impact test data were obtained from data published by the National Highway Traffic Safety Administration [NHTSA]. For all tests, force data were obtained from barrier load cells and stroke data were derived from accelerometers. Data from 53 truck and SUV tests were aggregated by vehicle product segment according to body style to obtain mean ± standard deviation (SD) stiffness corridors: (1) compact unibody SUV/crossover, (2) small unibody SUV/crossover, (3) mid-size unibody SUV/crossover, (4) frame SUV, and (5) frame truck. To compare between vehicle product segments, this study also considered the average stiffness (slope) within the stroke region required to achieve 300 kN total barrier force. Across unibody SUV segments, average stiffness varied from 1.4–1.8 kN/mm. Stiffness of frame SUVs and trucks was up to 93% higher than stiffness of unibody SUVs (2.7 vs. 1.4 kN/mm). Observed differences in stiffness corridors may have been due in part to unibody SUV design differences. For example, additional stroke (structure) was observed forward of the front axle comparing an exemplar mid-size SUV and frame SUV. In some cases, this structure may include a low stiffness bumper absorber. When stiffness corridors were offset to simulate a low stiffness initial geometry, better agreement between mean stiffness corridors was observed across vehicle segments. As unibody SUVs may continue to replace frame designs, future work should confirm directly the reasons for this stiffness difference in vehicle segments.

Hallman, Jason, Buck, Jessica, Ham, Suk Jae

Virtual Development of a Robust FlexPLI Impactor Surrogate for Sensor Tests at High Impact Speeds at Different Temperatures

2018-01-10504/3/2018

For fine-tuning of the parameters of algorithms used for activation of deployable pedestrian protection safety systems, quite a number of impact tests have to be performed on real vehicles. The impactors used for these purposes comprise misuse-objects, hardest-to-detect pedestrian impactors, but also impactors that represent larger pedestrians, such as the WG17 legform or the FlexPLI. Such tests are performed with impact speeds up to 55 kph and at ambient temperatures between −35 °C and 90 °C. Especially for the more complex FlexPLI there is a high risk of damage to the impactor under such conditions. Additionally, the required calibration procedures after such test series and an obligatory exchange of parts (e.g. ligaments) after each test are a source for further costs. Therefore, the aim of this study was the development of an impactor surrogate that correctly represents all relevant impact properties of the FlexPLI for sensor testing, but being much more robust, offering the simplest possible structure and therefore being also suited for repeated tests with impact speeds of up to 55 kph, without the need for replacement parts. Finally, it could be demonstrated that a simple impactor design, even without a knee joint, could fulfill these requirements very well. It is also shown in this study, how a fully parametrized impactor model has been used together with the optimization tool LS-OPT, to efficiently support the development process of such an impactor surrogate.

Pauer, Gernot, Svetina, Taja

Compact Device Can Detect Rheumatoid Arthritis

TBMG-2783611/1/2017

University of TwenteEnschede, The Netherlands

Electronic Bi-Directional Shift Control Design and Calibration for Farm Vehicle

2017-01-220510/8/2017

Agricultural tractors are often subjected to various applications like front end loading work, cultivation work, where frequent forward and reverse gears are needed. Most of Indian agricultural tractors are equipped with mechanical transmission system which demands repeated clutching and de-clutching operation for such applications resulting in increased operator fatigue and lesser productivity. Also need of electronics in Indian agricultural industry for better farm mechanization is growing high. This research work depicts development of electronic bi-directional shifting (power shuttle) control design and calibration for farm vehicle fitted with wet clutch transmission. This research also reduces operator fatigue via frequent directional shift through electronic transmission. The control system is designed without any electronic interfacing with engine and also provides clutch-less gear shifting and auto-launch which offers ease to drive even for novice driver. The power shuttle transmission control system offers more functionality and features in adjunct to in-built safety features without any additional sensors or components. Use of minimal sensor for system control and calibration delivers cost effect solutions. Adaptive control strategy is adopted for achieving efficient and optimal clutch fill modulation which is calibrateable for various climatic zone, vehicle loads, gears etc. Control software is designed by considering the vehicle variants pertinent to clutch load and engine characteristics. Modular control system design is employed in this research which can be extended across all tractor variants.

M A, Velmurugan, Rajagopal, MahendraMohan

Digital-to-Analog Transformation and Reconstruction of ECG Data

TBMG-272137/1/2017

The innovators at NASA Johnson Space Center have developed a new method and device for specialized digital-to-analog conversion (DAC) and reconstruction of multichannel electrocardiograms (ECGs), including 12-lead ECGs. Current devices do not have the functionality that allows for the transmission of stored digital ECG data collected from one manufacturer’s ECG machine to another for an automated second opinion. With this technology, the physician has the opportunity to compare results by transferring the ECG data to another ECG machine — regardless of location — when a patient’s results are difficult to interpret for a second opinion. The technology also allows for the use of less expensive 12-lead ECG front ends or analog-to-digital conversion (ADC) hardware that is advantageous when in remote locations or with patients who are mobile during research studies. The digital-to-analog transformation and reconstruction of ECG data technology is available for licensing.

Integration Drives the Future of Portable Healthcare Devices

TBMG-270086/1/2017

Lab on a Chip Minimizes Preterm Births

TBMG-267654/24/2017

With help from a palm-sized plastic rectangle with a few pinholes in it, researchers are hoping to minimize the problem of premature deliveries. The integrated microfluidic device is designed to predict, with up to 90 percent accuracy, a woman’s risk for a future preterm birth.

Pulse Analysis Techniques for Radar and Electronic Warfare

17AERP04_064/1/2017

Pulsed signals are widespread in radar and other electronic warfare (EW) applications, and they must be accurately measured for manufacturing, design of countermeasures, and threat assessment. Pulse measurements are an especially challenging area for signal analysis due to a combination of factors. Fortunately, many of the improving signal processing and analog-digital conversion technologies behind the generation of complex pulse environments also enable new techniques for effective pulse analysis. In the past, basic pulse measurements generally were made with swept spectrum analyzers. The intermediate frequency (IF) bandwidth or resolution bandwidth (RBW) of the spectrum analyzer was generally narrower than the effective bandwidth of the pulse, so the spectrum analyzer was used to measure the resulting pulse spectrum. The pulse spectrum could then be used to measure basic signal characteristics such as pulse repetition rate or interval (PRI), duty cycle, power, etc. Spectrum analyzers were also used in more traditional ways to make out-of-band measurements such as spurious and harmonics of pulsed signals.

Pulse Analysis Techniques for Radar and Electronic Warfare

TBMG-266734/1/2017

Experimental and Numerical Investigation of Vehicle Drive and Thermal Soak Conditions in a Simplified Engine Bay

2017-01-01473/28/2017

Driven by the demand to continuously reduce the development time of new vehicles, it is of critical importance to robustly develop design and packaging concepts early within a new vehicle program using CAE methods. As the underhood and underbody package is constantly getting tighter and the engine power increases, the development of a sophisticated heat protection concept requires much more attention. For many years, heat protection CAE is an integral part of the vehicle development at Ford. However, due to challenges related to transient analysis, e.g. high numerical effort, simulation of transient buoyancy driven airflow (thermal soak), and dependency on high quality thermal material properties, heat protection CAE was primarily focused on steady state vehicle operating conditions. Due to the constantly raising expectations towards CAE as a driver of vehicle design, an investigation has been carried out which aims to better understand the most influential factors impacting transient analysis, and in particular, thermal soak behavior. This investigation is expected to enable the development of an efficient numerical method to simulate this highly transient phenomenon. The present paper describes the design of a Soak Test Rig (STR) which mimics a vehicle front end but at the same time, provides a simplified and controlled environment for CAE method development. The tests carried out delivered a detailed view of the interior air and component temperature distribution for the steady-state preconditioning phase as well as throughout the transient thermal soak phase. Initial CAE analyses have been carried out and compared to test data. This overall investigation has led to an improved understanding of the underlying physics of thermal soak and led to the early phase development of a CAE process to predict thermal soak. The preliminary CAE method accurately predicts the trends in the measured data for three geometric configurations that were tested.

Sweetman, Brian, Schmitz, Ingo, Hupertz, Burkhard, Shaw, Nathanael, Goldstein, John

Functional Safety for Battery Monitoring Integrated Circuits

2017-01-12023/28/2017

The Battery Monitoring Integrated Circuit (BMIC) is a key technology for Battery Electronics in the electrification of vehicles. Generally speaking, every production hybrid, plug-in hybrid, and battery electric vehicle uses some type of BMIC to monitor the voltage of each lithium battery cell. In order to achieve Functional Safety for the traction battery packs for these electrified vehicles, most designs require higher ASIL ratings for the BMIC such as C or D. For the entire market of available BMIC’s, there is a generic feature set that can be found on almost every IC on the market, such as a front end multiplexer, one or more precision references, one or more Analog to Digital (A/D) converters, a power supply, communications circuits, and window comparators. There is also a fairly consistent suite of self-diagnostics, available on just about every available BMIC, to detect failures and enable achievement of the appropriate ASIL rating. This paper provides a generic approach for the use of these BMICs which is independent of the exact vehicle application and which is applicable to BMIC’s from all vendors. The functional safety concept which can be found in Battery Controller modules across OEMs is explained. Then, the usage of diagnostic features for these BMICs is examined in detail which is the final piece necessary to understand the technical safety requirements for battery pack electronics. Special emphasis is placed on the relationship between the specific diagnostic features which are offered by the silicon suppliers, and the implementation of these technical safety requirements.

Tabatowski-Bush, Ben

Building an Integrated Home Health Monitoring System

TBMG-262351/1/2017

Among the challenges faced by the healthcare sector is a population that is growing older. The elderly population is expected to grow significantly over the next 20 years. Having an independent lifestyle is highly desired by elderly people, but independence for older adults often comes with high risks. Many smart home technologies have been developed to track and monitor activities of the elderly at home and assist their independent living. Buildings and urban environments fitted out with sensor networks offer the elderly the chance to retain their independence for longer. Wearable sensor technologies can also play a major role.

Topologycal Optimization Applied to Design of an Automotive Hood

2016-36-021010/25/2016

The numerical simulation is currently an essential tool in the automotive engineering because it is possible in the virtual stage of product development to evaluate the performance of a component in the level of stress that would it be submitted, as well as evaluating displacement, natural frequency, stiffness and to the feasibility of manufacturing. Due to the stringent emission standards and pollutant, as well as sustainability guidelines, the goal of any automotive design is always seeking the maximum structural performance with minimal possible mass. This premise leads directly to a numerical optimization problem, that seeks the maximum (or minimum) of a function, subject to several constraints. Numerical optimization techniques can be divided mainly into: shape optimization, parametric optimization and topology optimization. In order to relieve mass during the process of forming it is common to perform a cutting operation to remove material in parts that are less required. In theory, this is characterized in a typical topology optimization problem, which consists in "holes" on the part topology, so as to remove the mass as possible without significant loss of performance. Thus, this work consisted of using topology optimization techniques to design the internal panel of a hood (hood inner panel) that provides the maximum ratio stiffness / mass to the entire hood. The results were compared with default settings found on the market and in which were evaluated the torsional stiffness, maximum stress, and natural frequencies. The results showed that the use of topology optimization for sheet metal forming are feasible and promising.

Resende, Marcelo Gustavo Coelho, Silveira, Márcio Eduardo, Resende, Tiago Alceu Coelho

Method and Apparatus for Measuring Surface Air Pressure

TBMG-2549310/1/2016

NASA’s Langley Research Center has developed a novel method for long-range atmospheric pressure sensing. Based on known properties involving oxygen density, the technology is able to measure small pressure changes over a wide area. NASA developed the technology to address known gaps in the area of weather forecasting as a result of the inability to accurately detect atmospheric pressure above the ocean. Oxygen band reading can be performed remotely, most likely from a satellite-based system. The technology is particularly applicable in the area of storm forecasting.

Biomimetics: nature leads the way on design

16MEIP06_186/1/2016

That bird flight inspired Leonardo da Vinci to conceptualize “flying machines,” only to be developed centuries later by the Wright brothers by observing pigeons in flight, is quite well known. Such imitation of the models, systems, and elements of nature for the purpose of solving complex problems, otherwise known as biomimetics or biomimicry, is not new. Mother Nature is a great engineer that over the years has fascinated engineers and scientists alike, who have borrowed and applied its time-tested patterns and strategies. Technological advancements and continuous endeavors to push the limits of engineering have led to transformational innovations, as can be seen in some of the recent trends to catch up with nature's best assets. Velcro is perhaps the best known and commercially successful example of a nature-inspired design. After a hunting trip in the Alps in 1941, Swiss engineer Mestral's socks and dog were covered in burdock burrs. Intrigued by it, Mestral studied them under a microscope to understand the simple system of interlocking hooks and spent the next few years developing Velcro. Such mimicking of nature's precise and efficient shapes, structures, and geometries is referred to as the basic level of biomimicry, by American biologist Janine Benyus.

High-Data-Rate Platform to Capture and Analyze Raw Baseband Clock/Data

TBMG-245205/1/2016

The Space Communications and Navigation (SCaN) Testbed has a need to capture and analyze high-datarate (<2 Mbps required) baseband information sent over RF by the JPL Software-Defined Radio (SDR). An RF4425 front end, coupled with a MicroGate Synclink USB and custom C++ software back end, is being used to answer this need.

Development of an Efficient Power Train Cooling System with Effective Utilization of Front End Opening for a Utility Vehicle

2016-01-06524/5/2016

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

Experimental Investigation with R1234yf Condenser Airflow Blockages of Non-Hotspot and Hotspot Objects to Impact on A/C System Performance

2016-01-02554/5/2016

This paper addresses R1234yf A/C system performance impacted by condenser airflow passage blockages of nonhotspot and hotspot objects. With the modern vehicle design trend, more and more chances exist in blocking condenser airflow passages by objects such as TOC (transmission oil cooler) or fine grills etc. These objects create hotspots and narrowed airflow passages to the condenser and result in A/C performance degradation. It is important to understand the specific area of the condenser which is most impacted by a blockage so this area can be avoided in the design/packaging of front end components. In addition, it is important to understand the magnitude of performance loss associated with the specific areas of blockage. As a result of this understanding, optimal design locations for these blockages (including hotspots and grilles) can be proposed in order to mitigate the impact on A/C cooling performance. The study indicated that blocking condenser airflow passages by both the hotspot and non-hotspot objects results in A/C performance degradation, i.e. increasing evaporator discharge air temperature and raising up compressor discharge pressure and temperature. With non-hotspot object blocking, the A/C performance with idle conditions has less impact than that with driving conditions. No significant difference for A/C performance impact between vertical and horizontal blockage was found. Hotspot object blockage located at the bottom of the condenser shows worse A/C performance than blockage located at the top of the condenser. A/C performance further degrades as the hotspot object temperature increases. From the study, it is concluded that in order to minimize A/C performance impact from condenser airflow passage blockages, the blocking object located at the top of the condenser is the better choice than that at the bottom of the condenser, assuming the blockage is unavoidable altogether. Thus, the larger grille opening should be reserved for the bottom of the condenser, and any hotspots should be at a low temperature if possible.

Zheng, Yinhua

Crushing Analysis and Lightweight Design of Tapered Tailor Welded Hybrid Material Tubes under Oblique Impact

2016-01-04074/5/2016

The increasing demand for lightweight design of the whole vehicle has raised critical weight reduction targets for crash components such as front rails without deteriorating their crash performances. To this end the last few years have witnessed a huge growth in vehicle body structures featuring hybrid materials including steel and aluminum alloys. In this work, a type of tapered tailor-welded tube (TTWT) made of steel and aluminum alloy hybrid materials was proposed to maximize the specific energy absorption (SEA) and to minimize the peak crushing force (PCF) in an oblique crash scenario. The hybrid tube was found to be more robust than the single material tubes under oblique impacts using validated finite element (FE) models. Compared with the aluminum alloy tube and the steel tube, the hybrid tube can increase the SEA by 46.3% and 86.7%, respectively, under an impact angle of 30°. Parameter analyses were performed to reveal the influence of four geometrical variables on the crashworthiness of the TTWTs. In addition, the radial basis function (RBF) metamodels were built for the SEA and PCF of the TTWTs, while the non-dominated sorting genetic algorithm (NSGA-II) was used to achieve the optimal solutions of the tube under oblique impact loads. The results show that the optimal solutions are different under different load angles and the solutions considering multiple load angles show more robust crashworthiness performance against oblique impacts. The proposed tapered hybrid tube has a potential application on vehicle bodies with improved crash performances under oblique loads.

Wang, Da-Zhi, Cao, Guang-Jun, Qi, Chang, Sun, Yong, Yang, Shu, Du, Yu

Uncertainty Optimization of Thin-walled Beam Crashworthiness Based on Approximate Model with Step Encryption Technology

2016-01-04044/5/2016

Crashworthiness is one of the most important performances of vehicles, and the front rails are the main crash energy absorption parts during the frontal crashing process. In this paper, the front rail was simplified to a thin-walled beam with a cross section of single-hat which was made of steel and aluminum. And the two boards of it were connected by riveting without rivets. In order to optimize its crashworthiness, the thickness (t), radius (R) and the rivet spacing (d) were selected as three design variables, and its specific energy absorption was the objective while the average impact force was the constraint. Considering the error of manufacturing and measurements, the parameters σs and Et of the steel were selected as the uncertainty variables to improve the design reliability. The algorithm IP-GA and the approximate model-RBF (Radial Basis Function) were applied in this nonlinear uncertainty optimization. In order to improve the accuracy of the RBF model, a new step-encryption technology was proposed, in which the encryption points will be added to the current sample points according to the results of each iteration. As a result, when the uncertainty level was 5%, the optimal design vector [t, R, d] was [1.75mm, 3.25mm, 29.48mm], and the possible interval of the specific energy absorption was [841J/kg, 1028J/kg] while the possible interval of constraint was [49.12KN, 71.39KN]. And the optimum was verified with the exact solver. Therefore, this study can provide important references for the crashworthiness design of the front rails.

Du, Qianqian

Noise Suppression System for AM Radio Receiver Using Quadrature Component of Receiving Signal

2016-01-00794/5/2016

Recently, the electromagnetic interference in an AM radio by the noise generated from a power control unit (DC-DC converters, inverters) in a hybrid vehicle (HV) has become a serious problem. To solve the problem, most noise suppression methods, for example, use noise filters for noise sources and shield wiring and ferrite cores for noise propagation paths. In this paper, we propose a noise suppression method using the digital signal processing in an AM radio receiver. In this method, first the receiving AM radio signal containing HV noise is quadrature demodulated. Next, a replica signal of the noise is generated by using the noise signal in the quadrature component. Then, the replica signal is subtracted from the AM radio signal containing the noise of the in-phase component. We construct a prototype of the radio receiver system based on this method and demonstrate that the system can reduce the HV noise superimposed on the AM radio signal by more than 20 dB. By applying this system to the radio receiver, it is expected that conventional noise suppression methods can be significantly simplified.

Harada, Tomohisa, Hattori, Yoshiyuki, Ito, Shinya, Fujimoto, Mitoshi, Hori, Toshikazu

Vehicle’s Front End Profile Influence on Pedestrian Sensing System Using In-House Developed PDI-2 and Child FE Models

2016-01-15104/5/2016

Many active safety systems are being developed with the intent of protecting pedestrians namely; pedestrian airbags, active hood, active emergency braking (AEB), etc. Effectiveness of such protection system relies on the efficiency of the sensing systems. The pop-uphood system was developed to help reduce pedestrian head injuries. A pop-up system is expected to make full deployment of the hood before the pedestrian’s head could hit the hood. The system should have the capability to detect most road users ranging from a six year old (6YO) child to a large male. To test the sensing system, an impactor model (PDI-2) was developed. Sensor response varies for vehicles with different front end profile dimensions. To study numerically the sensor response characteristics with respect to different front end parameters, (a) PDI-2 FE model was developed and validated, (b) FE model of sensor was developed and validated, (c) Sensor FE model was incorporated in the vehicle and it was simulated against the PDI-2 FE. The results were validated with physical experiments, (d) Vehicles with different front end profile models were developed and finally (e) Sensor response were studied using different vehicle designs simulated against PDI-2 FE and 6YO-child FE model. Results shows that for PDI-2 impacts, bumper height, bumper upper lead and bumper lower lead have influence in pressure sensor response. For 6YO-child impacts, the bumper height has influence in pressure sensor response.

Pal, Chinmoy, Okabe, Tomosaburo, Vimalathithan, Kulothungan, Manoharan, Jeyabharath, Vallabhaneni, Pratapnaidu, Shinada, Munenori, Sato, Kazuto

Engine Noise Reduction Using Self-Tuning Torsional Vibration Damper

2016-01-10634/5/2016

Nerubenko, George

Wideband, GaN MMIC, Distributed Amplifier-Based Microwave Power Module

TBMG-242624/1/2016

Historically, the term microwave power module (MPM) has been associated with a small, fully integrated, self-contained radio frequency (RF) amplifier that combines both solid-state and microwave vacuum electronics technologies. Typically, the output power of these MPMs is on the order of about 100 Watts CW over an octave bandwidth. The MPMs require both a solid-state amplifier at the front end and a microwave vacuum electronics amplifier at the back end. However, such MPMs cannot be utilized for communications because the MPMs are not optimized for linearity or efficiency. Also, the MPMs can be very expensive to manufacture, particularly when modules are produced in very small quantities for space applications. Also, a kilovolt (kV) class power supply is required to power the traveling-wave tube amplifier, which is a part of the microwave vacuum electronics.

BUDD-e concept forecasts what VW zero-emission van could be in 2019

16MEIP03_243/1/2016

At the 2016 CES in Las Vegas, Volkswagen attempted to focus attention away from its diesel engine emissions challenge by providing a glimpse into its electric future with an all-electric BUDD-e minivan concept. It would be the first model based on a new company “technology matrix” for electric vehicles called MEB, short for Modular Electric Drive Kit. Advantages of the MEB promised by VW include spacious interiors and the smallest possible traffic footprint; greater agility, acceleration, and maneuverability; distinct design identity thanks to new proportion and styling possibilities; and cost-effective access to e-mobility, accompanied by long ranges to match today's gasoline-powered cars. Better MEB packaging means that the HVAC system, for instance, can be completely integrated in the front end of the van, allowing for bigger and better filters and better acoustics due to a reduction in fan noise.

Jost, Kevin

Command and Data Handling for the Magnetospheric Multiscale Mission

TBMG-240953/1/2016

The Magnetospheric Multiscale (MMS) mission is the fourth mission of the Solar Terrestrial Probes (STP) program. The MMS mission, consisting of four identically instrumented spacecraft, will use Earth’s magnetosphere as a laboratory to study magnetic reconnection, a fundamental plasma-physical process that taps the energy stored in a magnetic field and converts it — typically explosively — into heat and kinetic energy in the form of charged particle acceleration and largescale flows of matter.

Multiple-Frequency-Band Software-Defined Radiometer

TBMG-236551/1/2016

Remote sensing — the use of spacebased satellite technologies to obtain information on environmental variables — in combination with other types of data, can provide information on changes in the Earth’s surface and atmosphere that are critical for weather forecasting and responding to human welfare issues (disease outbreaks, food shortages, and floods). Satellites and other remote sensing tools have gathered a great deal of useful data on the Earth’s climate systems, drainage systems, geologic structures, thermal anomalies, geomorphologic features, and distribution of vegetation.

Fixing Holes in Hearts with UV Light-Enabled Catheter

TBMG-2352512/1/2015

A multi-disciplinary team of Bostonarea researchers from Boston Children’s Hospital, the Wyss Institute for Biologically Inspired Engineering at Harvard University, Harvard’s John A. Paulson School of Engineering and Applied Sciences (SEAS), and the Karp Lab at Brigham and Women’s Hospital have jointly designed a specialized catheter that, they say, can fix holes in the heart using a biodegradable adhesive and patch. The catheter has been used successfully in animal studies to facilitate hole closure without the need for open heart surgery.

High-Performance Data Acquisition on USB

TBMG-22460

7/1/2015

A common belief among engineers is that in order to get the best performance, a PC-based data acquisition module must plug into the PCI bus. Properly implemented, however, a data acquisition module can use the PC’s USB port to pump data into a PC as fast as PCI-based cards. The keys to achieving this performance are a hardware USB interface on the module, and optimized driver software for the host system.

Some Aspects of Rigid Body Dynamics of Power Trains Using Dedicated Software with Respect to Noise and Vibration

2015-01-22566/15/2015

This paper considers important aspects of rigid body dynamics of power trains with respect to noise and vibration (by definition a power train (PT) term here is an engine plus transmission). Flexibility of PT's and their ancillaries leads to unwanted levels of noise and vibration. By employing rigid body concepts we can assess the levels of unwanted flexibility of whole PT's and their ancillaries e.g. mounting brackets. Using dedicated software based on rigid body theory it is possible to define vibration and noise ‘entitlement’ i.e. minimum vibration and noise that can theoretically be achieved. Targets can then be to set based upon these entitlements. This can then lead to better more robust designs to achieve higher levels of refinement. The use of generic 3 and 4 cylinder one liter in-line PT's modes are used within the software to aid this study. These PT's can be shown to adhere more to rigid body behavior due to their compact designs and lower (frequency) dominant orders of excitation. This paper steps through from basic understanding of rigid PT behavior then shows some rigid vibration and noise results for generic 3 and 4 cylinder PT's at key mount positions it then leads into leads onto how and why rigid vibration theory can help improve refinement with accompanying graphs and schematics to clarify understanding.

Troth, Colin

Design of Isolation Pulley in Front of Crankshaft to Reduce Vibrations of Front End Accessory Drive System

2015-01-22546/15/2015

The driving pulley is often used as a Torsional Vibration Damper (TVD) for the crankshaft in the front end accessory drive (FEAD) system. Although the crankshaft torsional vibrations are dampened, they are transmitted to the belt transmission and therefore to the driven accessories. The isolation pulley is a new device to reduce the belt tension fluctuation by isolating the belt transmission from the crankshaft torsional vibrations. A five-pulley system with isolation pulley is presented and a non-linear model is established to predict the dynamic response of the pulleys, tensioner motion, tension fluctuation and slippage. The model works in the time domain with Runge-Kutta time-stepping algorithm. The numerical simulation results of harmonic excitations show that the amplitudes of the belt tension fluctuation and the vibrations of each component are reduced significantly. Moreover, the effect of isolation pulley parameters on the system natural frequencies is demonstrated. It is shown that natural frequency of the system is reduced by using lower stiffness and thus the crankshaft torsional vibrations are isolated.

Shangguan, Wen-Bin, Feng, Xiao

Hazards Analysis Management Tool

TBMG-22028

5/1/2015

The Hazard Analysis Management Tool (HAMT) is comprised of a database and user interface that manages hazard analysis information, manages hazard verifications, and manages relationships between hazard attributes and project elements. The tool offers numerous benefits including the ability for multiple users to simultaneously update information, auto-generation of hazard reports, improved data consistency, ability to quickly obtain up-to-date status reports, and the ability to execute complex queries on the hazard information. This tool does not provide a mechanism for the identification of hazards. The tool requires minimal IT overhead and is easily tailored for specific projects and/or user groups. This tool was developed as a support capability, and testing was limited to the operational environment in which it was initially deployed.

Space Weather Database of Notifications, Knowledge, Information — DONKI

TBMG-22025

5/1/2015

SW DONKI is a comprehensive Web application for space weather forecasters, scientists, and the general space weather community. It serves as an archive for space weather activities including solar flares, coronal mass ejections (CMEs), solar energetic particles, and geomagnetic storms. An innovative feature of the system is the ability to generate, modify, and store complex linkages between space weather events — creating a comprehensive network of relationships between activities, and identifying potential cause-and-effect paradigms for each space weather event. SW DONKI also provides public access to all human-generated event analysis and notifications produced by the Space Weather Research Center (SWRC) forecasting team at CCMC (Community Coordinated Modeling Center).

Use of Truncated Finite Element Modeling for Efficient Design Optimization of an Automotive Front End Structure

2015-01-04964/14/2015

The present work is concerned with the objective of multi disciplinary design optimization (MDO) of an automotive front end structure using truncated finite element model. A truncated finite element model of a real world vehicle is developed and its efficacy for use in design optimization is demonstrated. The main goal adopted here is minimizing the weight of the front end structure meeting NVH, durability and crash safety targets. Using the Response Surface Method (RSM) and the Design Of Experiments (DOE) technique, second order polynomial response surfaces are generated for prediction of the structural performance parameters such as lowest modal frequency, fatigue life, and peak deceleration value. Using the lowest natural frequency of the front end, fatigue factor of safety and peak deceleration extracted from the NCAP crash pulse as constraint parameters, gages of bumper beam, front rails and shotguns as design variables, the mass of the front end structure (i.e. effectively the total mass of the parts mentioned) is optimized. The optimum solution is then obtained by using genetic algorithm functionality in commercial MATLAB package. The stated goal can be achieved by following either of the two different ways: using a Truncated model or a Full Car Model. Running CAE algorithms that include multi-disciplinary areas such as NVH and crash safety using RSM based method using a full car model is very time consuming. The results obtained from truncated model and the full vehicle model are compared and it has been found that the use of truncated model is substantially more efficient when compared to the use of full vehicle model and predicts nearly the same solution as the latter.

Deb, Anindya, Gunti, Ranga Srinivas, Chou, Clifford, Dutta, Utpal

Effect of Vehicle's Front End Profile on Pedestrian's Lower Extremity Injury Pattern in Real World and Verification by Large Male FE Human Model

2015-01-14674/14/2015

Logistic regression analysis for accident cases of NASS-PCDS (National Automotive Sampling System-Pedestrian Crash Data Study) clearly shows that the extent and the degree of pedestrian's lower extremity injury depend on various factors such as the impact speed, the ratio of the pedestrian height to that of the bonnet leading edge (BLE) of the striking vehicle, bumper to knee ratio, bumper lead angle, age of the pedestrian, and posture of the pedestrian at the time of impact. The pedestrian population is divided in 3 groups, equivalent to small-shorter, medium-height and large-taller pedestrian with respect to the “pedestrian to BLE height-ratio” in order to quantify the degree of influence of lower leg injuries in each group. Large adult male finite element model (95th percentile male: 190 cm and 103 kg) was developed by morphing the Japan Automobile Manufacturers Association (JAMA) 50th percentile male. Lower extremity of developed large male was fine meshed to predict the fractures accurately. A car model was systematically morphed to create different designs having various front end profile dimensions. Large male model with fine meshed lower extremity was impacted against those series of morphed vehicle models. Effect of vehicle's front end profile on lower extremity bone injuries was evaluated by accident analysis of PCDS data and their trends are verified by FE simulation of large male HBM. The results from accident analysis had good correlation with those obtained from FE simulations.

Pal, Chinmoy, Okabe, Tomosaburo, Vimalathithan, Kulothungan, Manoharan, Jeyabharath, Shinada, Munenori

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