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Journal Article

ERRATUM: Study of Reproducibility of Pedal Tracking and Detection Response Task to Assess Driver Distraction

2015-04-14
2015-01-1388.01
1. On page 111, the authors have described a method to assess driver distraction. In this method, participants maintained a white square size on a forward display by using a game gas pedal of like in car-following situation. The size of the white square is determined by calculating the distance to a virtual lead vehicle. The formulas to correct are used to explain variation of acceleration of the virtual lead vehicle. The authors inadvertently incorporated old formulas they had used previously. In the experiments discussed in the article, the corrected formulas were used. Therefore, there is no change in the results. The following from the article:
Journal Article

Measures to Prevent Unauthorized Access to the In-Vehicle E/E System, Due to the Security Vulnerability of a Remote Diagnostic Tester

2017-03-28
2016-32-0018
Remote diagnostic systems support diagnostic communication by having the capability of sending diagnostic request services to a vehicle and receiving diagnostic response services from a vehicle. These diagnostic services are specified in diagnostic protocols, such as SAE J1979, SAE J1939 or ISO 14229 (UDS). For the purpose of diagnostic communication, the tester needs access to the electronic control units as communication partners. Physically, the diagnostic tester gets access to the entire vehicle´s E/E system, which consists of connectors, wiring, the in-vehicle network (e.g. CAN), the electronic control units, sensors, and actuators. Any connection of external test equipment and the E/E system of a vehicle poses a security vulnerability. The combination can be used for malicious intrusion and manipulation.
Journal Article

Development and Testing of an Innovative Oil Condition Sensor

2009-04-20
2009-01-1466
In order to detect degradation of engine oil lubricant, bench testing along with a number of diesel-powered Ford trucks were instruments and tested. The purpose of the bench testing was primarily to determine performance aspects such as repeatability, hysteresis effects and so on. Vehicle testing was conducted by designing and installing a separate oil reservoir along with a circulation system which was mounted in the vicinity of the oil pan. An innovative oil sensor was directly installed on the reservoir which can measure five (5) independent oil parameters (viscosity, density, permittivity, conductance, temperature). In addition, the concept is capable of detecting the oil level continuously during normal engine operation. The sensing system consists of an ultrasonic transducer for the oil level detection as well as a Tuning Fork mechanical resonator for the oil condition measurement.
Journal Article

Optimizing Precision and Accuracy of Quantitative PLIF of Acetone as a Tracer for Hydrogen Fuel

2009-04-20
2009-01-1534
Quantitative planar laser-induced fluorescence (PLIF) of gaseous acetone as a fuel-tracer has been used in an optically accessible engine, fueled by direct hydrogen injection. The purpose of this article is to assess the accuracy and precision of the measurement and the associated data reduction procedures. A detailed description of the acetone seeding system is given as well. The key features of the experiment are a high-pressure bubbler saturating the hydrogen fuel with acetone vapor, direct injection into an optical engine, excitation of acetone fluorescence with an Nd:YAG laser at 266 nm, and detection of the resulting fluorescence by an unintensified camera. Key steps in the quantification of the single-shot imaging data are an in-situ calibration and a correction for the effect of local temperature on the fluorescence measurement.
Journal Article

Design of a Multi-Chamber Silencer for Turbocharger Noise

2009-05-19
2009-01-2048
A multi-chamber silencer is designed by a computational approach to suppress the turbocharger whoosh noise downstream of a compressor in an engine intake system. Due to the significant levels and the broadband nature of the source spanning over 1.5 – 3.5 kHz, three Helmholtz resonators are implemented in series. Each resonator consists of a chamber and a number of slots, which can be modeled as a cavity and neck, respectively. Their target resonance frequencies are tuned using Boundary Element Method to achieve an effective noise reduction over the entire frequency range of interest. The predicted transmission loss of the silencer is then compared with the experimental results from a prototype in an impedance tube setup. In view of the presence of rapid grazing flow, these silencers may be susceptible to whistle-noise generation. Hence, the prototype is also examined on a flow bench at varying flow rates to assess such flow-acoustic coupling.
Journal Article

Aspects of NVH Integration in Hybrid Vehicles

2009-05-19
2009-01-2085
NVH refinement is an important aspect of the powertrain development and vehicle integration process. The depletion of fossil-based fuels and increase in price of gasoline have prompted most vehicle manufacturers to embrace propulsion technologies with varying degrees and types of hybridization. Many different hybrid vehicle systems are either on the market, or under development, even up to all-electric vehicles. Each hybrid vehicle configuration brings unique NVH challenges that result from a variety of sources. This paper begins with an introductory discussion of hybrid propulsion technologies and associated unique vehicle NVH challenges inherent in the operation of such hybrid vehicles. Following this, the paper outlines a two-dimensional landscape of typical customer vehicle maneuvers mapped against hybrid electric vehicle (HEV) operational modes.
Journal Article

Numerical Simulations and Measurements of Mirror-Induced Wind Noise

2009-05-19
2009-01-2236
The high cost and competitive nature of automotive product development necessitates the search for less expensive and faster methods of predicting vehicle performance. Continual improvements in High Performance Computing (HPC) and new computational schemes allow for the digital evaluation of vehicle comfort parameters including wind noise. Recently, the commercially available Computational Fluid Dynamics (CFD) code PowerFlow, was evaluated for its accuracy in predicting wind noise generated by an external automotive tow mirror. This was accomplished by running simulations of several mirror configurations, choosing the quietest mirror based on the predicted performance, prototyping it, and finally, confirming the prediction with noise measurements taken in an aeroacoustic wind tunnel. Two testing methods, beam-forming and direct noise measurements, were employed to correlate the physical data with itself before correlating with simulation.
Journal Article

Realization of Ground Effects on Snowmobile Pass-by Noise Testing

2009-05-19
2009-01-2229
Noise concerns regarding snowmobiles have increased in the recent past. Current standards, such as SAE J192 are used as guidelines for government agencies and manufacturers to regulate noise emissions for all manufactured snowmobiles. Unfortunately, the test standards available today produce results with variability that is much higher than desired. The most significant contributor to the variation in noise measurements is the test surface. The test surfaces can either be snow or grass and affects the measurement in two very distinct ways: sound propagation from the source to the receiver and the operational behavior of the snowmobile. Data is presented for a known sound pressure speaker source and different snowmobiles on various test days and test surfaces. Relationships are shown between the behavior of the sound propagation and track interaction to the ground with the pass-by noise measurements.
Journal Article

Validation Study of a Generalized Minor Rear Vehicle Crash MADYMO Model Utilizing Real World Data

2009-06-09
2009-01-2264
A generalized MADYMO minor rear crash vehicle model with BioRIDII ATD was developed and validated using the mean response of previously published 12 km/h delta-V rear crash tests. BioRIDII simulation pelvis, thorax and head x-axis accelerations, as well as head y-axis angular acceleration, fell within corridors defining +/- one standard deviation of the mean BioRIDII crash test responses. Peak sagittal plane BioRIDII upper neck forces and moments in the simulation were on par with the mean values observed from the crash tests. After the model was validated for 12 km/h delta-V, the model was further exercised by performing simulations with (1) a Hybrid III 50th percentile occupant and (2) by reducing the pulse by 40% of its original value. Results indicate that this generalized minor rear crash model could be useful in accurately estimating occupant kinematics and kinetics in minor crashes up to at least 12 km/h delta-V as an alternative to expensive and time consuming crash testing.
Journal Article

Dynamic Analysis of Car Ingress/Egress Movement: an Experimental Protocol and Preliminary Results

2009-06-09
2009-01-2309
This paper focuses on full body dynamical analysis of car ingress/egress motion. It aims at proposing an experimental protocol adapted for analysing joint loads using inverse dynamics. Two preliminary studies were first performed in order to 1/ define the main driver/car interactions so as to allow measuring the contact forces at all possible contact zones and 2/ identify the design parameters that mainly influence the discomfort. In order to verify the feasibility of the protocol, a laboratory study was carried out, during which two subjects tested two car configurations. The experimental equipment was composed of a variable car mock-up, an optoelectronic motion tracking system, two 6D-force plates installed on the ground next to the doorframe and on the car floor, a 6D-Force sensor between the steering wheel and the steering column, and two pressure maps on the seat. Motions were reconstructed from measured surface markers trajectories using inverse kinematics.
Journal Article

International Space Station United States Operational Segment Crew Quarters On-orbit vs. Design Performance Comparison

2009-07-12
2009-01-2367
The International Space Station (ISS) United States Operational Segment (USOS) received the first two permanent ISS Crew Quarters (CQ) on Utility Logistics Flight Two (ULF2) in November 2008. As many as four CQs can be installed in the Node 2 element to increase the ISS crew member size to six. The CQs provide crew members with private space that has enhanced acoustic noise mitigation, integrated radiation-reduction material, communication equipment, redundant electrical systems, and redundant caution and warning systems. The rack-sized CQ system has multiple crew member restraints, adjustable lighting, controllable ventilation, and interfaces that allow each crew member to personalize his or her CQ workspace. The deployment and initial operational checkout during integration of the ISS CQ to Node 2 is described in this paper.
Journal Article

Main Design Factors and Unified Software Structure for Cable Puller and Caliper Integrated Type Electric Parking Brakes

2009-10-11
2009-01-3022
The main classification of Electric Parking Brakes (EPB) can be made into cable puller and caliper integrated types. In this paper, the main design considerations that need to be made for each type of system will be examined. In terms of mechanical design, actuator design factors including target capacity, system size, and vehicle mounting will be briefly discussed. In terms of software, a unified software structure that can incorporate both types of EPBs will be introduced. This unified approach, made up of fixed and variable modules, allows for more efficient software development for both types of EPB systems. The fixed modules are related to the identical target functions regardless of EPB type, while the variable modules are made up of the different considerations that need to be made depending on the EPB type in order to meet such targets. Finally, some test results of target functions for both types of EPB systems will be given.
Journal Article

Stability Analysis of a Disc Brake with Piezoelectric Self-Sensing Technique

2009-10-11
2009-01-3034
Piezoelectric self-sensing allows to measure frequency response functions of dynamical systems with one single piezoelectric element. This piezoceramics is used as actuator and sensor simultaneously. In this study, a model-based piezoelectric self-sensing technique is presented to obtain potential squealing frequencies of an automotive disc brake. The frequency-response function of the brake system is obtained during operation by measuring the current flowing through the piezoelectric element while the piezoelectric element is driven by a harmonic voltage signal with constant amplitude. The current flow is composed of the part which is required to drive the piezoelectric element as an actuator and a second part which is the sensor signal that is proportional to the vibration amplitude of the attached mechanical system. Typically the first part is dominant and the influence of the mechanical system is marginal.
Journal Article

Effects of Chemical Components and Manufacturing Process of Cast Iron Brake Disc on its Resonant Frequency Variation

2009-10-11
2009-01-3030
Many engineers have been working to reduce brake noise in many ways for a long time. So far, a progress has been made in preventing and predicting brake noise. Nevertheless, there are some discrepancies of brake noise generation propensity between testing for the prototype and the production. As known in general, the reason for this unpredicted brake noise occurrence in production is partly due to the variation of the resonant frequency, material and the other unpredictable or unmanageable variations of the components in a brake system. In this paper, effects of chemical components and casting process of gray iron brake disc on its resonant frequency variation have been studied. Especially this paper is focused on the variation in material aspects and manufacturing parameters during disc casting in usual production condition. And their effects are investigated by the variation of out-of-plane modal resonant frequency.
Journal Article

Current and New Approaches for Brake Noise Evaluation and Rating

2009-10-11
2009-01-3037
Predominant brake noise evaluation and rating was developed many years ago and no longer fulfills the need of modern development work. An extended description of a noisy brake event (European expert group guideline EKB 3006) and a standardized test data exchange format, allowing the comparison of different source test results (EKB 3008) are presented. Today's noise rating systems are described and compared by selected examples. The paper proposes an open 4 level noise rating system (EKB 3007). It starts with simple occurrence statistics, noise rating based on sound levels, situational noise rating including duration and finally based on the human perception, described by psychoacoustics.
Journal Article

Consideration of Critical Cornering Control Characteristics via Driving Simulator that Imparts Full-range Drift Cornering Sensations

2009-10-06
2009-01-2922
A driving simulator capable of duplicating the critical sensations incurred during a spin, or when a driver is engaged in drift cornering, was constructed by Mitsubishi Heavy Industries, Ltd., and Hiromichi Nozaki of Kogakuin University. Specifically, the simulator allows independent movement along three degrees of freedom and is capable of exhibiting extreme yaw and lateral acceleration behaviors. Utilizing this simulator, the control characteristics of drift cornering have become better understood. For example, after a J-turn behavior experiment involving yaw angle velocity at the moment when the drivers attention transitions to resuming straight ahead driving, it is now understood that there are major changes in driver behavior in circumstances when simulator motions are turned off, when only lateral acceleration motion is applied, when only yaw motion is applied, and when combined motions (yaw + lateral acceleration) are applied.
Journal Article

Fast Characterization of Brake Squeal Behavior

2009-10-11
2009-01-3006
The last decades have shown extensive efforts on the investigation of automotive disk brake squeal. The origin of brake squeal is seen in self-excited vibrations, caused by the friction forces transferring energy from the rotating disk into the brake system. Based on a very simple model, Popp et al. described in 2002 the conditions for positive work of the friction forces (i.e. excitation of squeal), which depends on the phase shift between the in-plane motion (with respect to the disk) of the brake pad and the friction forces. Experiments on active manipulation of this phase shift using pads with integrated piezoceramic actuators, performed by von Wagner et al. in 2004, resulted in successful suppression of disk brake squeal. The authors of the present paper used a variety of models for the investigation of the origin of the excitation mechanism by observing phase relations between the friction forces and the vibrations of the pads.
Journal Article

Evaluation of ANITA Air Monitoring on the International Space Station

2009-07-12
2009-01-2520
ANITA (Analysing Interferometer for Ambient Air) is a flight experiment precursor for a permanent continuous air quality monitoring system on the ISS (International Space Station). For the safety of the crew, ANITA can detect and quantify quasi-online and simultaneously 33 gas compounds in the air with ppm or sub-ppm detection limits. The autonomous measurement system is based on FTIR (Fourier Transform Infra-Red spectroscopy). The system represents a versatile air quality monitor, allowing for the first time the detection and monitoring of trace gas dynamics, with high time resolution, in a spacecraft atmosphere. ANITA operated on the ISS from September 2007 to August 2008. This paper summarises the results of ANITA's air analyses and compares results to other measurements acquired on ISS during the operational period.
Journal Article

Modeling and Calibration of Combine, Impact Plate, Yield Sensors

2010-10-05
2010-01-2002
An effort was undertaken to capture the relationship between the output of mass flow sensors and the input rate of mass flow for harvesting combines with yield monitors. Different types of models were considered that characterize this relationship and that can be applied to a variety of mass flow sensor technologies. Issues such as implementation during harvesting and calibration of these sensors and models were explored. Additionally, an example of such a model and its validation against experimental data was examined. For small-scale laboratory experiments, the model was shown to closely capture the general trend of the data as well as to yield reasonable estimates of the mass flowing through the system based on the sensor output. For large-scale experiments, the model was able to be fitted to the experimental data, and to estimate mass flow rate with relatively low errors across a variety of operating conditions.
Journal Article

Analysis of Ride Vibration Environment of Soil Compactors

2010-10-05
2010-01-2022
The ride dynamics of typical North-American soil compactors were investigated via analytical and experimental methods. A 12-degrees-of-freedom in-plane ride dynamic model of a single-drum compactor was formulated through integrations of the models of various components such as driver seat, cabin, roller drum and drum isolators, chassis and the tires. The analytical model was formulated for the transit mode of operation at a constant forward speed on undeformable surfaces with the roller vibrator off. Field measurements were conducted to characterize the ride vibration environments during the transit mode of operation. The measured data revealed significant magnitudes of whole-body vibration of the operator-station along the vertical, lateral, pitch and roll-axes. The model results revealed reasonably good agreements with ranges of the measured vibration data.
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