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Technical Paper

Driving Behaviour Analysis Software for Data-Driven Path Planning Functionalities for Automated Vehicles

2022-03-29
2022-01-0218
Autonomous driving is currently one of the most challenging Artificial Intelligence (AI) problems as it requires combination of state-of-the-art solutions in multiple areas including computer vision, sensor fusion, control theory and software engineering. Deep learning has been pivotal to solving some of these problems, especially in computer vision. This enabled some autonomous vehicle companies started leveraging the benefits of deep learning for creating smooth, natural, human-like motion planning systems. In particular, the plethora of driving data captured from modern cars is a key enabler for training data-driven path planning systems. , Developing deep learning-powered systems relies heavily on big and high-quality data required for training of the models, in which the intrinsic statistics of the data that the model is trained on can result in different agent behavior in different scenarios.
Technical Paper

Fatigue Damage of Trim Dies Manufactured or Reconditioned by Different Routes

2022-03-29
2022-01-0245
The compression fatigue behavior of sheet metal trimming die is studied. The trim dies were manufactured or reconditions through different fabrication processes and heat treatment conditions. An accelerated lab testing method is developed to evaluate die damage resistance under compressive cyclic load applied at the tool edge, analogous to sheet metal trimming die operation. The metal removal volume at the sheared edges were measured by image processing to quantify the degree of fatigue damage as a function of loading cycle number. The fatigue microstructural damage were examined with optical and scanning electron microscopies. The simulated die performances are compared among different die processing routes. A phenomenological trim die damage rate model in Paris law form was obtained and tuned with experimental data for tool life prediction.
Technical Paper

Technical Keynote: Durability Validation for Variable Vehicle Usage

2022-03-29
2022-01-0255
Durability engineering for vehicles is about relating real operational loading to the actual strength of the product and its components. In the first part of this presentation, we show how to calculate failure probabilities and safety factors based on the load and strength distributions. We discuss the uncertainty within the estimations, which is considerably large in case of extremely small failure probabilities as required for safety critical components. In the second part, we focus on modelling and simulating the loads based on real vehicle usage, such that the resulting statistics allows to understand and quantify the usage variability. The idea is, to simulate thousands of vehicle life spans of, say, 300.000 km or 15.000 h of operation each. The input data for such simulations typically consists of a combination of geographic data (like road network, topography, road conditions, traffic data, and points of interest) and properly segmented rich data from measurement campaigns.
Technical Paper

Monolithic Diesel Particulate Filters (DPF) substrate coated with CeO2-MnOx nanorods catalysts for soot oxidation

2022-03-29
2022-01-0547
Abstract Noble metal based Diesel Particulate Filters (DPF) are efficient aftertreatment devices to reduce the PM emissions of diesel engine at present. Because of the high-cost of noble metal, it is necessary to develop base metal soot combustion catalyst. In this work, CeO2-MnOx nanoparticles and nanorods catalysts were prepared by coprecipitation method using different precipitant. The crystal morphology of CeO2-MnOx nanomaterials is identified by a scanning electron microscope. The nitrogen physisorption and hydrogen temperature-programmed reduction results suggest that CeO2-MnOx nanorods has smaller specific surface area and greater redox capacity than CeO2-MnOx nanoparticles. The temperature programmed oxidation (TPO) tests were performed to evaluate the catalytic activity of the catalysts for soot oxidation. Results show that the CeO2-MnOx nanorods catalyst exhibits higher soot oxidation activity than CeO2-MnOx nanoparticles.
Technical Paper

Experimental and Numerical Investigation of Rim Aerodynamics

2022-03-29
2022-01-0891
The automotive industry is facing new emission regulations, changing customer preferences and technology disruptions. All have in common, that external aerodynamics plays a crucial role to achieve emission limits, reduce fuel consumption and extend electric driving range. Probably the most challenging components in terms of numerical aerodynamic drag prediction are the wheels. Their contribution to the overall pressure distribution is significant, and the flow topology around the wheels is extremely complicated. Furthermore, deltas between different rim designs can be very small, normally in the range of only a few drag counts. Therefore, highly accurate numerical methods are needed to predict rim rankings and deltas. This paper presents experimental and numerical results of four different production rim designs, mounted to a modified production car.
Technical Paper

Modification of the Lower Limb and the Pelvis for the Pedestrian Dummy

2022-03-29
2022-01-0851
In order to further reduce the pedestrian fatalities, the improvement of pedestrian safety performance of vehicles is needed. One of the way to further understand read-world pedestrian accidents is the evaluation by using a whole-body pedestrian dummy. In the past studies, the leg, the thigh and the pelvis of the pedestrian dummy were developed and improved. However, the requirements for the biofidelity of the pedestrian dummy have been improved in SAE J2782. Therefore, this study aimed to evaluate these responses of the past studies by using new requirements and to modify these parts that didn’t meet them. The force-defection curves from 3-point lateral bending tests for the leg and the thigh were compared with the corridors updated in SAE J2782. The biofidelity of the pelvis was evaluated in dynamic lateral compression tests of the isolated pelvis. The sacrum and the pubis force-deflection curves of the iliac or the acetabulum impact were compared with the corridors.
Technical Paper

Second-Row Children Fatalities in Front and Rear Crashes

2022-03-29
2022-01-0860
Objective: The protection of children in the second row in automotive crashes remains an important area of safety research. Field data is analyzed on second-row children in front and rear crashes to study fatality trends in 1980-2020 model-year vehicles and to investigate the safety improvements with higher head restraints, stronger front seats and increased use of restraint systems. Methods: 1990 to 2019 FARS was queried to assess the number of fatally injured second-row children (0-15 years old). The children included outboard occupants seated behind an occupied front seat and center occupants. The data was analyzed for rear and frontal crashes by calendar and model year. Results: The number of child fatalities decreased by calendar years and model years. There were 2.95-times more fatally injured children in frontal crashes than in the rear crashes. The relative risk decreased with MY (model year) of the vehicle.
Technical Paper

Rollover and near-rollover kinematics during evasive steer maneuvers

2022-03-29
2022-01-0855
We present 6-degree-of-freedom (6DOF) kinematic data from two SUVs during evasive steer maneuvers that did and did not result in rollovers. The vehicles were instrumented with a GPS speed sensor, tri-axial accelerometers, tri-axial angular rate sensors, and a steering wheel angle sensor. Drone-based and land-based video cameras recorded all tests. Six degree of freedom position/orientation data were extracted from the video using match moving techniques with 3D constraints from laser scans of the test site and vehicles as described in our previous SAE paper (SAE 2020-01-0272). The initial speeds varied from 100 to 124 km/h and the steering input during the tests were similar. We examine the magnitude and timing of the vehicle pre-roll kinematics to identify differences between the roll and non-roll events. We also present the 6DOF kinematics of the rollovers themselves. This study provides valuable insight into factors that predict roll initiation during evasive steer maneuvers.
Technical Paper

Development of Biomechanical Computational Models of Six-year-old Child Occupant with Different Sitting Postures and Application in the Study of Whiplash Injuries

2022-03-29
2022-01-0869
Whiplash injury is one of the main types of child occupant neck injuries in traffic accident. With the development of intelligent cockpit, child occupants will engage in traffic operation in various sitting positions. Therefore, studying the mechanism and risk of whiplash injury of child occupants with different sitting postures has important application value for the research and development of child restraint system. In this study, the 120° and 135° sitting postures of six-year-old child occupant were developed based on the validated 105° sitting posture finite element model with detailed anatomical structure. The whiplash test in Euro NCAP was reconstructed to evaluate the influence of sitting position angle on the risk of whiplash injury. In the three groups of simulation experiments, the Upper Neck Tension (Fz) was far less than the higher limit of Euro NCAP evaluation although the Fz value increased as the upper torso angle increases.
Technical Paper

Vehicle Dynamics Analysis and Optimization of Electric All-Terrain Vehicle

2022-03-29
2022-01-0913
A Vehicle Dynamics Analysis of an electric All-Terrain Vehicle (ATV) was conducted and has been presented in the following paper. Having analyzed the performance and understood the reasons behind the shortcomings, solutions to optimize the vehicle design were implemented. These optimizations were tested and results were compared with the pre-existing model and planned to be validated by conducting physical trials on the actual model. The tests were conducted on a Multi-Body Dynamics tool: MSC Adams Software and results obtained from the tests have been put forth in theoretical as well as graphical manner to get a clearer view. This research involved a thorough study of Lateral and Longitudinal Dynamics of the ATV. Trends in dynamic parameters like the ride quality, pitch response, roll stability, yaw response, camber gain and other important parameters of the vehicle were studied and its correlation with the feedback obtained from the driver was established.
Technical Paper

Observer-Based Torque Vector Control of a Four In-wheel Motor-driven Electric Vehicles Considering with Unbalanced Electric Magnetic Field

2022-03-29
2022-01-0915
The accuracy and range of chassis control for a four in-wheel motor (IWM)-driven electric vehicles (EVs), especially in observer-based EVs control for improving road handling and ride comfort, is a challenging task for the IWM-driven vehicle system. Due to the high fatality rate caused by inaccurate state-based control algorithm, how to precisely acquire movement state and chose the reasonable observer-based control algorithm for IWM-driven EVs become a hot topic in both academia and industry. Simultaneously, uncertainty is always existing, e.g., varying road excitation, variable system parameters or nonlinear structure. Meanwhile, the coupling effects between the non-ideal IWM actuator and vehicle are ignored under the assumption of an ideal actuator.
Technical Paper

Visualization of Frequency Response Using Nyquist Plots

2022-03-29
2022-01-0753
Nyquist plots are a classical means to visualize a complex vibration frequency response function. By graphing the real and imaginary parts of the response, the dynamic behavior in the vicinity of resonances is emphasized. This allows insight into how modes are coupling, and also provides a means to separate the modes. Mathematical models such as Nyquist analysis are often embedded in frequency analysis hardware. While this speeds data collection, it also removes this visually intuitive tool from the engineer’s consciousness. The purpose of this paper is to review the fundamentals of Nyquist plots and their application to structural vibration. The behavior of a single degree of freedom system will be shown to be well described by a circle on its Nyquist plot. This observation allows simple visual examination of the response of a continuous system, and the determination of quantities such as uncoupled natural frequencies, modal damping factors, and uncoupled modes shapes.
Technical Paper

The Gods' Light: A Novel Full Factorial Light Environment Control System with Vision System & Dark Photonic Channel Illuminant for Means of Transportation

2022-03-29
2022-01-0803
Imagination is a real factor in scientific research. One of the most important elements of productive scientific research is to find out the right direction & clear goal. Take automobile lighting as an example, daylight lighting is generally acceptable for driving safety. So, therefore, one of the effective research methods to first simulate and approximate the daytime light environment as much as possible by vehicle lighting at night is the right direction and a clear goal. The three golden principles of safe driving are concentration, watch carefully, and prevent in advance. All of these safety rules strictly require the driver to take everything around the vehicle as a safe driving factor.
Technical Paper

Luminance Estimation with Exemplar Digital Camera

2022-03-29
2022-01-0804
Mapping the luminance values of a visual scene is of broad interest to accident reconstructionists, human factors professionals, and lighting experts. Previous work has shown that pixel intensity captured by consumer-grade digital still cameras can be calibrated to estimate luminance. Suway and Suway presented a methodology for estimating luminance from digital images and video of a scene. This method requires the capture of dark images close in time to the capture of the image that will be used to estimate luminance. Additionally, Suway’s method requires the specific camera and lens combination used to be calibrated for luminance estimation. In this paper, the authors present results of estimating luminance with an exemplar camera and taking exemplar dark images. The analysis was completed with the commercially available luminance estimation software, Nitere.
Technical Paper

Factors Influencing the Effectiveness of a Center-Mounted Airbag in Reducing Occupant Excursion and Injury Potential in High-Speed Lateral Impacts

2022-03-29
2022-01-0843
A substantial percentage of serious and fatal injuries sustained by motor vehicle occupants occur in lateral impact collisions, and approximately one third of these injuries involve a far-side occupant. A center airbag, deploying inboard of the front seat occupants, has been integrated into certain vehicles to reduce far side occupant excursion, limit occupant interactions with the vehicle interior and/or another occupant, and reduce occupant loading and injury potential in high speed lateral impacts. A series of sled tests was conducted to better understand the efficacy and limitations of the center airbag under a variety of high speed lateral impact conditions. An automotive driver’s seat equipped with a seat-mounted center airbag was installed onto an open air sled. A Hybrid III 50th percentile SID Anthropomorphic Test Device (ATD) was placed in the seat and restrained by a three-point seat belt equipped with retractor and buckle pretensioners.
Technical Paper

A Comparison of Mobile Phone Lidar Capture and Established Ground based 3d Scanning Methodologies.

2022-03-29
2022-01-0832
Ground-based LiDAR using FARO 3d scanners and other brands of scanners have been shown to be an accurate way to capture the geometry of accident scenes, accident vehicles and exemplar vehicles, as well as corresponding evidence from these sources such as roadway gouge marks, vehicle crush depth, and burn areas. However, ground-based scanners do require expensive and larger equipment to be brought on-site, as well as other materials that may be required depending on the scenario. New technologies, such as Apple’s mobile phone LiDAR capture, have been released recently in their newer model phones, and they offer a chance to obtain similar results but with less cumbersome and less expensive equipment. This technology embeds photos with lidar data that can then be exported into point cloud data using different applications available in the app store. This paper will investigate the accuracy of Apple mobile phone LiDAR on obtaining geometry from multiple exemplar vehicles.
Technical Paper

Geometric Derivation of Camera Equations

2022-03-29
2022-01-0831
Photogrammetry, camera matching, and model-based image matching are commonly used techniques to analyze video for accident reconstruction and other forensic applications. Investigators are often tasked with determining the speed of a vehicle, person, or other object in a video of an incident, or with taking measurements from photographs. All such calculations are based on fundamental geometric principles governing image projection inside a camera. Most treatments in the literature express the image projection equations either in very simple terms for specific cases or in compact matrix notation that is difficult to apply. The purpose of this paper is to present a geometric derivation of the image projection equations in a straightforward form that can be readily applied by a qualified investigator without the need for specialized software. In addition, a simple brute force optimization procedure is described to perform camera matching and model-based image matching.
Technical Paper

A study of the Performance of Autonomous Emergency Braking Systems when presented with Pedestrian Targets

2022-03-29
2022-01-0824
This paper reviews and analyzes the testing conducted by the IIHS with respect to Automatic Emergency Braking systems equipped on passenger vehicles when presented with a pedestrian hazard ahead. The paper addresses the differences in how vehicles respond to a moving and stationary pedestrian, the difference in vehicle behaviour if the pedestrian is initially not visible, and the differences in vehicle behaviour when the hazard is a stopped vehicle vs. a pedestrian. Finally, the paper addresses differences in human performance and vehicle behaviour when faced with a pedestrian in motion
Technical Paper

Using the Instantaneous Center of Rotation to Examine the Influence of Yaw Rate on Occupant Kinematics in Eccentric Planar Collisions

2022-03-29
2022-01-0826
The reconstruction of planar vehicle-to-vehicle collisions often requires a kinematic analysis of post-impact occupant motion to assist with biomechanical injury assessment. When one vehicle imparts an eccentric force on the adverse vehicle, the resulting vehicle kinematics include both translation and rotation. The influence of vehicle yaw on occupant kinematics has been well established. The role that the vehicle yaw has with regard to occupant injury potential is dependent upon a number of factors, including delta-V, vehicle intrusion, occupant seating position, restraint use, and yaw rate. Assuming rotation about the vehicle center of gravity or trivializing post-impact rotation may overlook aspects of the collision dynamics that have important implications for post-impact occupant motion. This study examines the significance of vehicle yaw on occupant kinematics and the evaluation of injury potential in eccentric planar collisions.
Technical Paper

US EPA NVFEL Repeatable-Vehicle Program – Emission Lab Testing System Performance Quality Monitoring

2022-03-29
2022-01-0568
According to US FCR the vehicle emission testing system must be monitored and checked periodically, and NVFEL TATD has developed a quality control monitoring program named “Repeatable-Vehicle Program”, the current vehicle selected is a proper sized and featured sedan, so called RepCar. The vehicle emission lab cell test used a chassis dyno to simulate some road driving conditions, a CVS system to collect exhaust sample and analyzed by a group of chemical benches. The testing condition is satisfied the FCR requirement and controlled during the testing procedure. A specific driving cycle including two phases was designed to evaluate vehicle power system at different speed load performance and measurement instruments accuracy under different concentration range. The phase1 is modified FTP505, phase2 is the most aggressive part of US06, and at the end of phase2 driving trace had a 30-second constant 75 mph cruising followed by a coast down.
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