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Autonomous vehicles may attract more passengers to recline their seat for comfort. However, under severe rear-end crashes and large reclining angle, the backward inertia could completely throw occupant out of seat. Even if the occupant body can be restrained by seatbelt, the occupant’s head could slide out of the head restraint area. Any of these situations may cause severe injuries. To address this safety concern, we developed a sliding seat system designed to enhance occupant retention. Activated by impact inertia of rear-end collision, the system allows the seat sliding backward along its track in a controlled manner, and the sliding stroke is accompanied by a restraint force and absorbs some amount of kinetic energy during the sliding. Thus, occupant retention can be enhanced, and injury risks of head and neck can be reduced. To demonstrate this concept, we built a MADYMO model and conducted a parametric analysis. The model includes a 50th percentile human model, a vehicle seat
Dai, RuiZhou, QingPuyuan, TanShen, Wenxuan
This paper presents the multidisciplinary development of a hybrid automotive hood manufactured using double-shot injection molding with overmolded brackets. Conventional steel and aluminum hoods, while structurally reliable, pose challenges in terms of weight reduction, pedestrian head protection, and manufacturing cost. Composite and thermoplastic alternatives supported by computational analysis and advanced molding processes provide opportunities to address these challenges. Finite element analysis (FEA) was employed to evaluate torsional and bending stiffness, locking load, and crashworthiness, while pedestrian headform simulations following ECE R127 and EEVC WG17 guidelines were conducted to assess compliance with safety regulations. Adhesion and bonding strength of overmolded polymer–polymer interfaces were studied to validate manufacturing feasibility. Results confirm that hybrid hoods fabricated using multi-material double-shot molding can achieve weight reductions of up to 30
Ganesan, KarthikeyanSeok, Sang HoJo, Hyoung Han
Vehicle-to-vehicle sideswipe collisions are unique in their impact characteristics because the vehicles typically do not reach a common velocity at impact. To better understand the characteristics and dynamics of sideswipe collisions, vehicle-to-vehicle crash testing was performed to find the relationships between variables related to the impact, such as closing speed, relative angle, and overlap depth. This paper discusses data collected for three sideswipe (oblique) impact tests conducted at a testing facility in Buffalo, New York. The tests were conducted using a passenger vehicle as the sideswiping vehicle, which impacted a stationary cargo van. The passenger vehicle was towed into the van at relative angles ranging from 8 to 15 degrees and at velocities of 5 to 20 mph. Two different (but identical) passenger cars and two cargo vans were used during the testing series. Test results were then utilized to investigate a methodology of analyzing sideswipe collisions as a combination of
Danaher, DavidMcDonough, SeanDonaldson, AndrewNeale, WilliamCochran, Reece
Industries are following a tedious product development cycle for developing their product. In product development major steps includes design ideas, Drawings, CAD, CAE, Testing and design improvement cycle. This is a monotonous process and takes time which impacts on its time to deliver product and cost on development. Now a days industries are fast growing and targeting to reduce development cycle time and cost. AI&ML is impacting almost all areas in the industry and significantly reducing efforts time and cost. To make use of AI&ML in CAE, Altair Physics AI is an effective tool. To ensure the design of product traditional way is to develop a CAD of the product, develop, perform CAE and analyze performance. If we consider CAE procedure it is time consuming process which includes FEA model build, applying boundary conditions, running simulation and analyzing results which could take minutes to hours. By using ML with Physics AI we can make predictions on new design of the product in
Dangare, Anand ManoharKulkarni, Mandar
Battery thermal runaway is a major safety concern in electric vehicles because of the extreme heat and hazardous gases released during cell failure. These venting events can quickly raise the temperature of the battery enclosure and cabin floor, threatening occupant safety. To address this challenge, this study employs the Design for Six Sigma (DFSS) methodology to design and optimize a thermal protection system that delays and limits heat transfer to the cabin. A physics-based transient heat-transfer model was combined with DFSS principles to systematically evaluate insulation materials, shield layouts, surface emissivity, and layer geometry. An L-18 orthogonal array was used to identify key parameters and quantify their influence on thermal robustness. The optimized architecture reduced cabin-floor temperature rise under severe runaway conditions (600–900 °C vent gas), meeting occupant-egress safety requirements. Findings confirm DFSS as an effective framework for developing high
El-Sharkawy, AlaaAsar, MonaTaha, NahlaSheta, Mai
Compared to regular fuels, biofuels can play a key role as low-carbon transitional energy sources for ICE vehicles as the fleet moves towards increasing electrification. Blending of ethanol plays a key role in enhancing the anti-knock properties of the fuel and also allows renewable hydrocarbons (such as bio-naphtha) to be incorporated into the blend whilst maintaining an acceptable overall fuel quality. Super lean burn ICE technology with λ between 2 and 3 can lead to enhanced fuel economy and reduced NOx emissions. The Toyota prototype engine used to generate data for this project injects most of the fuel in PFI mode to generate a homogeneous super-lean charge in the cylinder, but just before spark ignition the DI injector sprays a small amount of fuel towards the spark plug to create a richer charge near the spark plug to promote flame kernel development. Various fuel formulations with high biofuel content were tested in both conventional and super lean burn engines. Certain fuel
Aradi, AllenKrueger-Venus, JensJain, Sandeep KumarCracknell, RogerKolbeck, AndreasShibuya, MasahikoYamada, RyotaMatsubara, NaoyoshiKitano, Koji
Lightweighting of components has become a key challenge in the development of modern transportation systems. In the automotive and aerospace industries, the overall mass of a vehicle has a significant impact on its fuel efficiency and manufacturing cost. Therefore, the lightweight design of vehicle components is crucial in the industrial field. Topology optimization (TO) is a computational design approach aimed at achieving lightweight designs. However, most existing studies focus on simplified academic models, with limited demonstration in real-world applications. This paper presents a revised TO workflow to obtain production-ready design and a practical implementation of TO in the design of three structural components in the aerospace industry: seatback frame, seat fuselage mount, and seat spreader. The revised TO workflow incorporates the practical demands of industry, including enhanced manufacturability and cost efficiency through TO design. The resulting designs are evaluated to
Lee, Hanbok JakeShi, YifanGray, SavannahOrr, MathewPark, TaeilWotten, ErikLeFrancois, RichardHuang, YuhaoPatel, AnujKim, HansuJalayer, ShayanBurns, NicholasHansen, EricGrant, RobertKok, LeoKim, Il Yong
Flying cars have already been used in tourism, firefighting, and logistics, and might be soon used for short-distance commute. However, the lumbar spine injury risks in flying car crash accidents have raised safety concerns. This is because the crash load of a flying car is largely aligned with the orientation of the occupant’s spine. This study introduces a countermeasure of actively adjusting seat posture for mitigating lumbar injury in crash events. A flying car crash usually has a few seconds of warning time before collision to ground. The pre-impact warning time is enough to rotate the seat and occupant together using seat motors. Posteriorly rotating seat can alter the angle between the crash load and the spinal axis, thereby reducing lumbar injury risk. Using numerical simulations, the 30g deceleration pulse defined in SAE-AS-8049 was applied to seat of flying car. The THUMS (Total Human Model for Safety) human body model was used to model occupant, sitting in a typical vehicle
Zhuang, ZiaoPuyuan, TanShen, WenxuanZhou, QingGu, Gongyao
With the rapid proliferation of electrified vehicles (xEVs), maximizing regenerative energy recovery has become a crucial challenge in realizing zero-emission mobility. In front-wheel-drive (FWD) vehicles, regenerative braking acts only on the front axle, resulting in a braking-force distribution biased toward the front. When uniform hydraulic pressure is applied to both axles, excessive braking force on the front wheels may cause premature wheel lock and hinder the intended regenerative braking effect. To address this issue, it is essential to implement an independent pressure control strategy (two-channel pressure control) that appropriately reduces front pressure according to regenerative force while independently maintaining adequate rear pressure. This study proposes a new two-channel pressure control architecture utilizing a simple and reasonable actuator set consisting of one electric cylinder and one solenoid valve. The electric cylinder generates hydraulic pressure by
Kaneko, ShosukeDeno, YoshitomoKobayashi, TatsushiKawamura, Hikaru
Foam material models for automotive structural analysis typically require tensile and compressive data at multiple strain rates. The testing is costly and may require a long time to complete. For many applications, foams of similar chemistry are used and the foam structural responses, such as stiffness and compression force deflection, are controlled by the foam density. In such cases, Machine Learning (ML) lends itself as an ideal tool to detect the trends in material response based on density and strain rate. In this paper, two sets of polyurethane (PU) foams of different densities were tested at four strain rates ranging from 0.01/s to 100/s. ML models capable of predicting compressive stress-strain response for a range of densities were developed. The models demonstrated good prediction capability for intermediate strain rates at all foam densities and in extrapolating stress-strain curves at higher densities at all strain rates. The strain rate trends for density outside of the
M, Gokula KrishnanKavimani, HarishMuppana, Sai SiddharthaSavic, VesnaChavare, SudeepV S, Rajamanickam
The Argon Power Cycle (APC) is an emerging high-efficiency combustion technology for internal combustion engines. In APC, the conventional air-based working fluid is replaced with an inert argon gas. This substitution inherently increases engine efficiency through thermodynamic properties of argon, in particular a high adiabatic factor ?? ~1.67. A hydrogen-fueled APC engine offers the potential for highly efficient zero emission combustion by also eliminating nitrogen oxide (NOx) formation. In the present paper, hydrogen combustion is studied in an optical heavy-duty research engine, with the objective of providing the first visualization of H2 combustion in an argon–oxygen mixture. A comparative analysis of high-speed optical imaging and in-cylinder pressure measurements is conducted for two different modes: 1) conventional air operation and 2) argon-oxygen mixture operation. The high-speed images reveal a distinctly different combustion process between the two operating modes. The
Kapp, JoakimCheng, QiangKaario, OssiVuorinen, Ville
A methodology for performing Human Operator Modeling (HOM) using a Caterpillar Model 299D3 XE Compact Track Loader (CTL) is presented. The proposed method uses task analysis techniques to decompose material excavation and moving tasks into smaller, individual tasks presented in a task list. A method for verifying and refining the task list is presented, along with a procedure for identifying relevant human operator sensory information and analyzing human decision making in the context of CTL operation. This methodology is then partially verified through the analysis of a non-expert human operator in Vortex Studio, a realistic construction equipment simulator. A modified test course is executed by a non-expert human operator in the simulation environment, and the recorded data is used to create a quantitative Human Operator Model. From this, a Virtual Operator Model (VOM) feedback controller simulating the performance of the human operator is developed. The VOM is implemented using a
Wang, Orson R.Norris, William R.Patterson, Albert E.Soylemezoglu, AhmetNottage, Dustin S.
The advancement of electric vehicles necessitates a rigorous focus on passenger cabin safety, particularly concerning the severe thermal hazard of a lithium-ion battery thermal runaway. Unlike internal combustion engine vehicles, electric vehicles require interior materials that provide superior thermal resistance to slow heat propagation, delay autoignition, and minimize smoke and toxic gas emissions, thereby securing a survivable evacuation window. This paper examines the application of the lumped-capacitance thermal model and the derived thermal time constant (τ) as a foundational framework for evaluating and selecting cabin materials. This approach enables a quantitative, physics-based ranking of materials—including seat composites, sound-deadening layers, electrical insulation, and carpet assemblies—based on their intrinsic ability to delay their own temperature rise under transient heat flux. By integrating materials with a high τ and elevated critical failure temperatures, this
El-Sharkawy, AlaaTaha, NahlaAsar, MonaSheta, Mai
The utilization of gasoline engines in heavy-duty vehicles for the purpose of continental transportation is in direct competition with conventional diesel engines. It’s imperative that the operating performance of the gasoline engine is equivalent to the diesel engine, and that the gasoline engine shows efficiency benefit to both cost segments, the product manufacturing costs and total cost of ownership (TCO). The 11.6-liter gasoline engine developed has been designed and applicated in such a way that it operates at a stoichiometric combustion air ratio (λ = 1) across the entire engine map range without exception. In combination with external exhaust gas recirculation (EGR) this strategy does not result in a substantial decrease in the absolute NOx concentration in raw emissions compared to the diesel engine with 15.0-liter displacement, but it facilitates the cost-efficient utilization of the three-way catalyzer as the main exhaust aftertreatment system, thereby reducing NOx emissions
Medicke, MarioArnold, ThomasBohme, JanKrause, MatthiasLeesch, Mirko
The car body consists of many parts, between which there are cavities and gaps that water, dust, and noise can enter. To prevent corrosion and reduce noise, these gaps are sealed with a paste featuring complex non-Newtonian properties. Sealing also serves a cosmetic function for visible areas, which demands high quality for better customer satisfaction. Usually, bead length can reach several meters with a height of 0.5-5 mm and a width of 5-40 mm. In this situation, optimizing the robotic paths and sealant flow can speed up production and reduce costs. Accurate and fast CFD modeling helps with planning the sealing process, shortening vehicle development cycles and minimizing costs. Due to the complexity of vehicle body geometry, arbitrary robotic movements, sealing bead length, free surface, and the complex rheological material properties, traditional CFD simulations have difficulties in modelling this process. This paper presents a new framework for modelling the sealing processes
Panov, Dmitrii OlegovichZhu, HuaxiangBasic, JosipZhang, LingranKotian, AkhileshMenon, MuraleekrishnanBorra, Ravi KanthAndo, Yuya
Crashworthiness assessment is a critical aspect of automotive design, traditionally relying on high-fidelity finite element (FE) simulations that are computationally expensive and time-consuming. This work presents an exploratory comparative study on developing machine learning-based surrogate models for efficient prediction of structural deformation in crash scenarios using the NVIDIA PhysicsNeMo framework. Given the limited prior work applying machine learning to structural crash dynamics, the primary contribution lies in demonstrating the feasibility and engineering utility of the various modeling approaches explored in this work. We investigate two state-of-the-art neural network architectures for modeling crash dynamics: MeshGraphNet, a graph neural network that is widely employed in physics-based simulations, and Transolver, a transformer-based architecture with a physics-aware attention mechanism designed to maintain linear computational complexity with respect to geometric
Nabian, Mohammad AminChavare, SudeepAkhare, DeepakRanade, RishikeshCherukuri, RamTadepalli, Srinivas
The mechanical properties of 3D printed composites have been shown to vary due to the manufacturing infill direction due to artifacts from the printing process. PEEK (Polyether Ether Ketone) and PEEK reinforced with carbon fiber were studied for these experiments because they are widely used for their high strength properties. 3D printed composites that behave with anisotropic characteristics have been evaluated under Laminate Composite Theory (LCT), which can be used to determine the mechanical properties of these 3D printed composites. By changing the orientation of the extruded strands in a 3D printed part, the structure can be optimized in a specific orientation for specific loading conditions, and LCT can be applied for simulating mechanical responses. Three point bending tests were performed on rectangular 3D printed samples and compared to a 3D simulation using LCT for a similar bending load. This allows for the use of LCT in combination with a finite element software such as
Bradley, CoilinGarcia, JordanSibley, Brian
Moving ground wind tunnels offer a more accurate test environment for ground vehicle drag coefficient measurement due to their highly realistic representation of the boundary layer phenomenon. However, historically most vehicles have been tested on static ground wind tunnels. As a result, the measured drag coefficient of these vehicles may not be sufficiently realistic for certification purposes. Therefore, it is valuable to build statistical models to estimate moving ground wind tunnel drag coefficient by using information from a static ground wind tunnel and other relevant vehicle characteristics such as presence of aerodynamic devices (spoilers, air dams, etc.). However, to build accurate statistical models, appropriate predictive features must be identified as a first step. In this paper, an aerodynamic feature selection study has been conducted to identify vehicle characteristics that contribute to drag coefficient estimation discrepancies between a static- and a moving ground
Singh, YuvrajJayakumar, AdithyaRizzoni, Giorgio
The intersection of Safety of Intended Functionality (SOTIF) and Functional Safety (FuSa) analysis of driving automation features has traditionally excluded Quality Management (QM) components from rigorous safety impact evaluations. While QM components are not typically classified as safety-relevant, recent developments in artificial intelligence (AI) integration reveal that such components can contribute to SOTIF-related hazardous risks. Compliance with emerging AI safety standards, such as ISO/PAS 8800, necessitates re-evaluating safety considerations for these components. This paper examines the necessity of conducting holistic safety analysis and risk assessment on AI components, emphasizing their potential to introduce hazards with the capacity to violate risk acceptance criteria when deployed in safety-critical driving systems, particularly in perception algorithms. Using case studies, we demonstrate how deficiencies in AI-driven perception systems can emerge even in QM
Abbaspour, Ali RezaMahadevan, ShabinZwirglmaier, KilianStafford, Jeff
This paper presents research and digital twin modeling results to support work on a methodology to properly account for the energy consumed by the thermal system of a BEV, for use within both existing Petroleum-Equivalent Fuel Economy (PEFE) calculations, and the proposed addition of hot and cold weather range values to the consumer-facing Monroney label [1]. Properly accounting for thermal system impacts would incentivize minimizing energy consumption of these systems, since 1) BEV PEFE is a direct input to an OEMs overall CAFE performance, and 2) the values on the Monroney label has some impact on consumer vehicle choice. The impetus for this work was Final Rules issued by the EPA and NHTSA in early 2024 eliminating A/C Efficiency Credits for BEVs from the 2027 MY, thus eliminating regulatory incentives to minimize energy consumption of these systems. Higher energy consumption will produce a number of negative secondary effects, including higher real-world greenhouse gas emissions
Taylor, Dwayne
The goal of this study is to quantify the accuracy (bias) and precision (uncertainty) of the time, position, and speed data acquired by a range of consumer-grade devices (4 bike computers, 5 watches, 1 application on 3 smart phones, and a camera) that access Global Positioning System (GPS) satellite signals. We acquired data at each device’s maximum sampling rate (typically 1 Hz) during 207 minutes (twelve sessions of ~17 min) over 61.6 km of road cycling. The time and position data from these devices were compared to real-time kinematic (RTK) data acquired using a differential GPS system, and speed data from these devices were compared to a high-resolution wheel speed sensor synchronized to the RTK data in order to statistically estimate the bias and 95th percentile confidence intervals of the uncertainty of the devices’ data. Overall, we found the position and speed data from the devices generally lagged the reference by 4 s or less, although the lags between the speed and position
Booth, Gabrielle R.Mitchell, Alan L.Siegmund, Gunter P.
Crashes involving passenger vehicles increasingly include vehicles equipped with infotainment systems that are unsupported by commercial vehicle system forensics hardware and software. Examiners facing these systems must overcome challenges in acquiring and analyzing user data, requiring an understanding of both digital forensics principles and the proprietary characteristics of the modules. This paper presents a methodology for acquiring data from previously unsupported Lexus infotainment modules, including techniques to bypass CMD42 security locks on SD cards and extract data. Once acquired, the paper outlines methods for analyzing user data through data carving techniques, enabling recovery of information from binary images even when the full file system cannot be reconstructed. Emphasis is placed on maintaining the integrity of the evidence and validating findings through controlled testing. These validation procedures ensure that the recovered information is both accurate and
Burgess, Shanon
Pedestrian fatalities in traffic accidents continue to rise, with severe injuries often resulting from both vehicle impact and subsequent ground contact, frequently occurring outside the field of view of vehicle-mounted cameras. This study presents a proof-of-concept (PoC) approach for reconstructing three-dimensional pedestrian motion—including occluded regions—using dashcam video. The method integrates 2D human pose estimation (MMPose) and monocular depth estimation (Depth Anything V2),the latter was fine-tuned on a custom dataset, to generate 3D skeletal coordinates.To evaluate motion matching, the reconstructed pedestrian poses were quantitatively compared with a database of vehicle collision simulations using the THUMS human body model and skeletal data representing real-world crash scenarios generated in PC-Crash. Composite similarity indices based on thoracic center of gravity trajectory and torso orientation vectors were employed for this comparison. Preliminary results
Onishi, KojiWang, KewangUno, ErikoIchikawa, KojiTanase, NoboruAndo, Takahiro
Toyota vehicles equipped with Toyota Safety Sense (TSS) can record detailed information surrounding various driving events. Often, this data is employed in accident reconstruction to better understand the dynamics of a collision. TSS data is comprised of three main categories: Vehicle Control History (VCH), Freeze Frame Data (FFD), and image records. During an event, it is possible that a vehicle undergoes a catastrophic power loss from the damage sustained during the event. In this paper, the effects of sudden power loss on the VCH, FFD, and images are studied. Events are triggered on a TSS 3.0 equipped vehicle by driving toward a stationary target. After system activation, a total power loss is induced, triggered on the instrument cluster “BRAKE” alert message, at various delays after activation. This testing studies various signals recorded across VCH, FFD and image data including vehicle speed and time and date. Results show that there is a minimum time to record after system
Getz, CharlesYeakley, AdamDiSogra, Matthew
As internal combustion engines continue to play a critical role in hybrid on-road and numerous non-road applications, there is a continued push to increase efficiency and minimize tailpipe emissions. However, reduced investment in new engine architectures means retrofittable technologies are favored to continue incremental performance improvements to existing engine platforms. To maintain the relatively low capital cost of engine-based powertrains, these technologies must be low-cost and compatible with the diverse mix of fuels that may be encountered across various market segments in the future. Pre-chambers have shown significant potential for improving spark-ignited engine performance across a wide range of engine sizes, from motorsport applications to stationary power, and operating conditions, from stoichiometric operation to ultra-lean. Understanding the degree to which this central combustion technology must be tailored to optimize its performance with a variety of fuels and
Peters, NathanPothuraju Subramanyam, SaiHoth, AlexanderBunce, Michael