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High Speed Camera Based 3D Experimental Modal Analysis

University of Ljubljana-Domen Gorjup, Janko Slavic, Miha Boltezar
  • Technical Paper
  • 2020-01-1569
To be published on 2020-06-03 by SAE International in United States
High-speed camera systems in vibration measurements are typically limited to identifying motion perpendicular to the optical axis. Depth information, lost in the imaging process, can be recovered by using the recently introduced frequency domain triangulation and consequently full 3D deflection shapes can be obtained. This research presents the required theoretical background where the multiview image data is used for spatial small harmonic motion identification. Vibrations of an arbitrary-shaped specimen can be identified in the frequency domain using only a single, moving high-speed camera, extending the field-of-view of the established image-based vibration measurement methods. Real test cases are also presented.
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Development of a Camera-Based Driver State Monitoring System for Cost-Effective Embedded Solution

Hitachi America, Ltd.-Xunfei Zhou, Tobias Wingert, Maximilian Sauer, Subrata Kundu
  • Technical Paper
  • 2020-01-1210
To be published on 2020-04-14 by SAE International in United States
To prevent the severe consequences of unsafe driving behaviors, it is crucial to monitor and analyze the state of the driver. Developing an effective driver state monitoring (DSM) systems is particularly challenging due to limited computation capabilities of embedded systems in automobiles and the need for finishing processing in real-time. However, most of the existing research work was conducted in a lab environment with expensive equipment while lacking in-car benchmarking and validation. In this paper, a DSM system that estimates driver's alertness and drowsiness level as well as performs emotion detection built with a cost-effective embedded system is presented. The proposed system consists of a mono camera that captures driver's facial image in real-time and a machine learning based detection algorithm that detects facial landmark points and use that information to infer driver's state. In the detection module, driver's distraction level is evaluated by estimating head-pose through solving a perspective-n-point problem, drowsiness level is estimated by processing eyelid related parameters extracted from facial keypoints data, and machine learning approach was used for emotion state monitoring.…
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A Co-Simulation Platform for Powertrain Controls Development

Hyundai-Kia America Technical Center Inc.-Shihong Fan, Yong Sun, Jason Hoon Lee, Jinho Ha
  • Technical Paper
  • 2020-01-0265
To be published on 2020-04-14 by SAE International in United States
With the advancement of simulation software development, the efficiency of vehicle and powertrain controls research and development can be significantly improved. Traditionally, during the development of a new control algorithm, dyno or on-road testing is necessary to validate the algorithm. Physical testing is not only costly, but also time consuming. In this study, a virtual platform is developed to reduce the effort of testing. To improve the simulation accuracy, co-simulation of multiple software is suggested as each software specializes in certain area. The Platform includes Matlab Simulink, PTV Vissim, Tass Prescan and AVL Cruise. PTV Vissim is used to provide traffic environment to PreScan. PreScan is used for ego vehicle simulation and visualization. Traffic, signal and road network are synchronized in Vissim and PreScan. Powertrain system is simulated in Cruise. MATALB/Simulink serves as master of this co-simulation, and integrates the different software together. It also includes human driver model and a powertrain control function. An ADAS-ISG (Idle Stop and Go) powertrain control algorithm is implemented in Simulink and tested by using the platform under different…
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A Stability-Guaranteed Time-Delay Range for Feedback Control of Autonomous Vehicles

Yildiz Technical University-Ahmet Kirli, Mehmet Selçuk Arslan
  • Technical Paper
  • 2020-01-0090
To be published on 2020-04-14 by SAE International in United States
The vehicles with level-5 autonomy (L5AVs) have no human driver in the loop are also known as self-driving cars. L5AVs are assumed the next generation of ground transportation, which have growing attention from both industry and academia in most recent years. Most of the work related to feedback strategies of L5AVs are on developing mapping systems through a variety of sensors. These systems can be considered as an analogue to the perception and central nervous system of human drivers. For instance, innovative visualization systems are more powerful when compared to the visual perception system of a person, yet, mapping demands high computation loads. This burden causes delay in the feedback loop and thus, it might have an unfavorable influence on proper and safe control action. This study investigates the effect of time delay occurring in mapping systems on the stability of the controlled vehicle. An algorithm entitled as “Cluster Treatment of Characteristic Roots - CTCR” is used to calculate a safe delay range as a remedy for the time delay caused by mapping systems. The…
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Study of thermal efficiency improvement by multi-hole nozzle

Hino Motors Ltd.-Kazunori Yoshitomi, Yoshihiro Funayama, Mori Ishii, Hiroshi Nakajima
  • Technical Paper
  • 2020-01-0304
To be published on 2020-04-14 by SAE International in United States
A truck and bus transportation which support logistics and people, diesel engines are highly expected to have high thermal efficiency and low exhaust emissions over the next few decades. Effective methods to achieve even higher thermal efficiency are to reduce a cooling loss from combustion chamber wall. A multi-hole diesel injector has a significant impact on improving engine thermal efficiency by enhancing a combustion activity and reducing a cooling loss. In this study, two types of diesel injectors – 8-hole and 14-hole - with the same flow rate were tested under heavy-duty diesel engine condition. Heat release rate, energy balance and engine emissions were investigated using the single-cylinder engine with displacement of 1,478 cc. Furthermore, an optical engine was used to observe quantitative spray penetration and flame development from shadowgraph imaging and analyze flame temperature by a two-color method. The results of the single-cylinder engine showed that the 14-hole injector exhibited higher indicated thermal efficiency thanks to lower cooling loss than 8-hole results. However, we observed a slightly higher exhaust loss in the case of…
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An Image Recognition Application Method for Vertical Movement of Vehicles

Wuhan University of Technology-Ming Li, Gangfeng Tan, Zhenyu Wang, Haoyu Wang, Yifeng Jiang, Donghua Guo, Jiaming Feng
  • Technical Paper
  • 2020-01-0733
To be published on 2020-04-14 by SAE International in United States
In ITS, image processing technology is applied to a wide variety of areas such as visual-based intelligent vehicle navigation, visual-based traffic monitoring and visual-based traffic management. In the identification system of the vehicle body characteristics, most of the recognition is the license plate and the car emblem, etc. This paper proposes an image recognition application method for the vertical motion of the car while driving, mainly including vertical height detection and vertical displacement velocity acceleration recognition. The edge detection model of the image object is established by using the gray image to obtain the car motion segmentation image. At the same time, an image length and actual length coordinate conversion model is established, which can calculate an arbitrary actual length of the image object. In this paper, the Yuejin Shangjun X500 van is selected as the test vehicle. Using camera capture the video data and the height of the vehicle is recognized for each frame. The height is compared with the actual length. The absolute error can be controlled within 40mm, and the minimum relative…
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Understanding How Rain Affects Semantic Segmentation Algorithm Performance

Mississippi State Univ-John Ball
Mississippi State University-Suvash Sharma, Chris Goodin, Matthew Doude, Christopher Hudson, Daniel Carruth, Bo Tang
  • Technical Paper
  • 2020-01-0092
To be published on 2020-04-14 by SAE International in United States
Research interests in autonomous driving have increased significantly in recent years. Several methods are being suggested for performance optimization of autonomous vehicles. However, weather conditions such as rain, snow, and fog may hinder the performance of autonomous algorithms. It is therefore of great importance to study how the performance/efficiency of the underlying scene understanding algorithms vary with such adverse scenarios. Semantic segmentation is one of the most widely used scene-understanding techniques applied to autonomous driving. In this work, we study the performance degradation of several semantic segmentation algorithms caused by rain for off-road driving scenes. Given the limited availability of datasets for real-world off-road driving scenarios that include rain, we utilize two types of synthetic datasets. The first dataset is a pure synthetic rainy dataset which considers the rain droplets on a camera lens, which is suitable for an autonomous vehicle with outside-mounted cameras. This data is generated by the MAVS simulator. In the second dataset, we take good-weather imagery and artificially incorporate rain streaks. By investigating different simulated rain rates, we quantify the performance…
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Simultaneous Visualization of Natural Luminosity and Chemiluminescence of Dual Fuel Combustion in an Optically Accessible Engine

Aalto University-Qiang Cheng, Zeeshan Ahmad, Ossi Kaario, Martti Larmi
  • Technical Paper
  • 2020-01-0309
To be published on 2020-04-14 by SAE International in United States
The engine fueled with methane/diesel is a promising and highly attractive operation mode due to its high performance-to-cost ratio and clean-burning qualities. However, the combustion process and chemical reactions in dual fuel combustion are highly complex, involving short transient pilot-fuel injection into the premixed gaseous fuel charge, autoignition, and combustion mode transition into premixed flame propagation. The motivation of the current investigation is to gain an insight into the combustion dynamics in dual fuel combustion engine based on chemical radicals and thermal radiation. The chemiluminescence (CL) and natural luminosity (NL) are expected to provide specific characteristics in combustion control and monitoring. To visualize the highly unsteady combustion process in terms of OH*, CH2O* radicals and natural luminous emissions, the band pass filters with 308 nm, 330 nm combined with an image doubler are employed to visualize the OH* and CH2O* CL simultaneously. High speed natural luminosity imaging is adopted to illustrate the effects methane lambda and pilot ratio on the ignition delay, luminous intensity and engine performance. Spectroscopy analysis based on OH*, CH2O* and NL…
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Sound Evaluation of Flow-Induced Noise with Simultaneous Measurement of Flow Regimes at TXV Inlet of Automotive Evaporators

University of Illinois-Stefan Elbel
University of Illinois at Urbana-Champaign-Yingyue Zhang
  • Technical Paper
  • 2020-01-1255
To be published on 2020-04-14 by SAE International in United States
In the air conditioning system, flow-induced noise is very disturbing, including the noise generated in the expansion device and the heat exchangers. In the past few decades, most researches related to flow-induced noise focused on the relationship between the flow regimes near the expansion device and the amplitude of flow-induced noise when the measurements are not synched. In this paper, an experimental approach is used to explore the simultaneous relationships between flow-induced noise characteristics and flow regimes at the inlet of TXV of evaporators used in automobiles. A pumped R134a loop with microphones and transparent visualization sections is used to simulate the vapor compression system. Also, the paper evaluates the severity of flow-induced noise from not only the amplitude of noise but also the frequency of noise with a parameter called psychoacoustic annoyance (PA). One of the most disturbing flow-induced noise types near the TXV is called gurgling noise and distributes around 9 kHz at an amplitude between 40 dB to 50 dB. When the TXV inlet is subcooled, the annoyance of flow-induced noise is…
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Pedestrian Head Impact, Automated Post Simulation Results Aggregation, Visualization and Analysis using d3VIEW

FCA Engineering India Pvt. Ltd.-Sreenath Mallela
FCA US LLC-Milind Shivaji Parab
  • Technical Paper
  • 2020-01-1330
To be published on 2020-04-14 by SAE International in United States
Pedestrian head impact regulation mandates the reduction of head injuries, measured using Head-Impact-Criteria (HIC). Virtual tools driven design comprises of simulating the impact on the hood and post processing the results. Due to the high number of impact points, engineers spend a significant portion of their time in manual data management, processing, visualization and score calculation. Moreover, due to large volume of data transfer from these simulations, engineers face data bandwidth issues particularly when the data is in different geographical locations. This deters the focus of the engineer from engineering and also delays the product development process. This paper describes the development of an automated method using d3VIEW that significantly improves the efficiency and eliminates the data volume difficulties there by reducing the product development time while providing a higher level of simulation results visualization. This method significantly reduces post-simulation analysis time and completely eliminates the effort of manual data management and visualization. d3VIEW is tightly integrated with LS-DYNA and since raw LS-DYNA data is processed on HPC, the resulting output data stored in d3VIEW server…