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Technical Paper

Deep Reinforcement Learning Based Collision Avoidance of Automated Driving Agent

2024-04-09
2024-01-2556
Automated driving has become a very promising research direction with many successful deployments and the potential to reduce car accidents caused by human error. Automated driving requires automated path planning and tracking with the ability to avoid collisions as its fundamental requirement. Thus, plenty of research has been performed to achieve safe and time efficient path planning and to develop reliable collision avoidance algorithms. This paper uses a data-driven approach to solve the abovementioned fundamental requirement. Consequently, the aim of this paper is to develop Deep Reinforcement Learning (DRL) training pipelines which train end-to-end automated driving agents by utilizing raw sensor data. The raw sensor data is obtained from the Carla autonomous vehicle simulation environment here. The proposed automated driving agent learns how to follow a pre-defined path with reasonable speed automatically.
Technical Paper

Development of a Dynamic Nonlinear Finite Element Model of the Large Omnidirectional Child Crash Test Dummy

2024-04-09
2024-01-2509
The Large Omnidirectional Child (LODC) developed by the National Highway Traffic Safety Administration (NHTSA) has an improved biofidelity over the currently available Hybrid III 10-year-old (HIII-10C) Anthropomorphic Test Device (ATD). The LODC design incorporates enhancements to many body region subassemblies, including a redesigned HIII-10C head with pediatric mass properties, and the neck, which produces head lag with Z-axis rotation at the atlanto-occipital joint, replicating the observations made from human specimens. The LODC also features a flexible thoracic spine, a multi-point thoracic deflection measurement system, skeletal anthropometry that simulates a child's sitting posture, and an abdomen that can measure belt loading directly. This study presents the development and validation of a dynamic nonlinear finite element model of the complete LODC dummy. Based on the three-dimensional CAD model, Hypermesh was used to generate a mesh of the finite element (FE) LODC model.
Technical Paper

Compatibility Between Vehicle Seating Environments and Load Legs on Child Restraint Systems (CRS)

2024-04-09
2024-01-2751
Load legs on child restraint systems (CRS) protect pediatric occupants by bracing the CRS against the floor of the vehicle. Load legs reduce forward motion and help manage the energy of the CRS during a crash. As more CRS manufacturers in the United States (US) consider incorporating these safety features into their products, benchmark data are needed to guide their design and usage. The objective of this study is to develop benchmark geometrical data from both CRS and vehicle environments to help manufacturers to incorporate compatible load legs into the US market. A sample of vehicle environments (n=104 seating positions from n=51 vehicles, model years 2015 to 2022) and CRS with load legs (n=10) were surveyed. Relevant measurements were taken from each sample set to compile benchmark datasets. Corresponding dimensions were compared to assess where incompatibilities might occur.
Technical Paper

Automated TARA Framework for Cybersecurity Compliance of Heavy Duty Vehicles

2024-04-09
2024-01-2809
Recent advancements towards autonomous heavy-duty vehicles are directly associated with increased interconnectivity and software driven features. Consequently, rise of this technological trend is bringing forth safety and cybersecurity challenges in form of new threats, hazards and vulnerabilities. As per the recent UN vehicle regulation 155, several risk-based security models and assessment frameworks have been proposed to counter the growing cybersecurity issues, however, the high budgetary cost to develop the tool and train personnel along with high risk of leakage of trade secrets, hinders the automotive manufacturers from adapting these third party solutions. This paper proposes an automated Threat Assessment & Risk Analysis (TARA) framework aligned with the standard requirements, offering an easy to use and fully customizable framework. The proposed framework is tailored specifically for heavy-duty vehicular networks and it demonstrates its effectiveness on a case study.
Technical Paper

Flow-Acoustic Coupling in Quarter-Wave Resonators Using Computational Fluid Dynamics

2001-04-30
2001-01-1430
Quarter-wave resonators are commonly used as acoustic silencers in automotive air induction systems. Similar closed side branches can also be formed in the idle air bypass, exhaust gas recirculation, and positive crankcase ventilation systems of engines. The presence of a mean flow across these side branches can lead to an interaction between the mean flow and the acoustic resonances of the side branch. At discrete flow conditions, this coupling between the flow and acoustic fields may produce high amplitude acoustic pressure pulsations. For the quarter-wave resonator, this interaction can turn the silencer into a noise generator, while for systems where a valve is located at the closed end of the side branch the large pressure pulsations can cause the valve to fail. This phenomenon is not limited to automotive applications, and also occurs in natural gas pipelines, aircraft, and numerous other internal and external flows.
Technical Paper

Testing and Modeling of Elevator Door Retention During Hallway Applied Lateral Loads

2009-06-09
2009-01-2273
Most do not consider there to be a risk in pushing on, bumping into or falling against an elevator door from the hallway side. However, the lack of the elevator cars presence alone, and the potential for severe injury or even death make this seemingly mundane situation potentially critical. Standards exist relative to such situations, and past and current designs attempt to account for this possibility, still people get injured interacting with these doors every year. In order to evaluate a real-world elevator door system's ability to withstand the quasi-static and impactive loads that can be placed on it by the general public during its life, both intentionally and unintentionally, a predictive tool is needed. This work represents the combination of empirical laboratory testing and numerical modeling of a typical elevator door system exposed to quasi-static and dynamic loading.
Journal Article

Comparison of Adult Female and Male PMHS Pelvis and Lumbar Response to Underbody Blast

2024-04-17
2023-22-0003
The goal of this study was to gather and compare kinematic response and injury data on both female and male whole-body Post-mortem Human Surrogates (PMHS) responses to Underbody Blast (UBB) loading. Midsized males (50th percentile, MM) have historically been most used in biomechanical testing and were the focus of the Warrior Injury Assessment Manikin (WIAMan) program, thus this population subgroup was selected to be the baseline for female comparison. Both small female (5th percentile, SF) and large female (75th percentile, LF) PMHS were included in the test series to attempt to discern whether differences between male and female responses were predominantly driven by sex or size. Eleven tests, using 20 whole-body PMHS, were conducted by the research team. Preparation of the rig and execution of the tests took place at the Aberdeen Proving Grounds (APG) in Aberdeen, MD. Two PMHS were used in each test.
Technical Paper

Data-Driven Estimation of Coastdown Road Load

2024-04-09
2024-01-2276
Emissions and fuel economy certification testing for vehicles is carried out on a chassis dynamometer using standard test procedures. The vehicle coastdown method (SAE J2263) used to experimentally measure the road load of a vehicle for certification testing is a time-consuming procedure considering the high number of distinct variants of a vehicle family produced by an automaker today. Moreover, test-to-test repeatability is compromised by environmental conditions: wind, pressure, temperature, track surface condition, etc., while vehicle shape, driveline type, transmission type, etc. are some factors that lead to vehicle-to-vehicle variation. Controlled lab tests are employed to determine individual road load components: tire rolling resistance (SAE J2452), aerodynamic drag (wind tunnels), and driveline parasitic loss (dynamometer in a driveline friction measurement lab). These individual components are added to obtain a road load model to be applied on a chassis dynamometer.
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