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The analysis presented in this document demonstrates the mathematical model approach for determining the rotation of a door about the hinge axis. Additional results from the model are the torque due to gravity about the axis, opening force, and the door hold open check link force. Vector mechanics, equations of a plane, and parametric equations were utilized to develop this model, which only requires coordinate points as inputs. This model allows for various hinge axis angles and door rotation angles to quickly be analyzed. Vehicle pitch and roll angles may also be input along with door mass to determine the torque about the hinge axis. The vector calculations to determine the moment arm of the door check link and its resulting force are demonstrated for both a standard check link design and an alternate check link design that has the link connected to a slider translated along a shaft.

THOR-AV 5F, a modified THOR-5F dummy, was designed to represent both upright and reclined occupants in vehicle crashworthiness studies. The dummy was evaluated in four test conditions: a) 25° seatback, 15 km/h, b) 25° seatback, 32 km/h, c) 45° seatback, 15 km/h, d) 45° seatback, 32 km/h. The dummy’s biomechanical responses were compared against those of postmortem human subjects (PMHS) tested in the same test conditions. The latest National Highway Traffic Safety Administration (NHTSA) BioRank method was used to provide a biofidelity ranking score (BRS) for each data channel in the tests to assess the dummy’s biofidelity objectively. The evaluation was categorized into two groups: restraint system and dummy. In the four test conditions, the restraint system showed good biofidelity with BRS scores of 1.49, 1.47, 1.15, and 1.79, respectively.

With the current trend of including the evaluation of the risk of brain injuries in vehicle crashes due to rotational kinematics of the head, two injury criteria have been introduced since 2013 – BrIC and DAMAGE. BrIC was developed by NHTSA in 2013 and was suggested for inclusion in the US NCAP for frontal and side crashes. DAMAGE has been developed by UVa under the sponsorship of JAMA and JARI and has been accepted tentatively by the EuroNCAP. Although BrIC in US crash testing is known and reported, DAMAGE in tests of the US fleet is relatively unknown. The current paper will report on DAMAGE in NCAP-like tests and potential future frontal crash tests involving substantial rotation about the three axes of occupant heads. Distribution of DAMAGE of three-point belted occupants without airbags will also be discussed. Prediction of brain injury risks from the tests have been compared to the risks in the real world.

Frontal-crash sled tests were conducted to assess submarining protection and abdominal injury risk for midsized male occupants in the rear seat of modern vehicles. Twelve sled tests were conducted in four rear-seat vehicle-bucks with twelve post-mortem human surrogates (PMHS). Select kinematic responses and submarining incidence were compared to previously observed performance of the Hybrid III 50th-percentile male and THOR-50M ATDs (Anthropomorphic Test Devices) in matched sled tests conducted as part of a previous study. Abdominal pressure was measured in the PMHS near each ASIS (Anterior Superior Iliac Spine), in the inferior vena cava, and in the abdominal aorta. Damage to the abdomen, pelvis, and lumbar spine of the PMHS was also identified. In total, five PMHS underwent submarining. Four PMHS, none of which submarined, sustained pelvis fractures and represented the heaviest of the PMHS tested. Submarining of the PMHS occurred in two out of four vehicles.

In this paper, experimental studies were conducted to examine the mechanical behavior of a polymer composite material called polyamide with glass fiber (PA6-GF), which was fabricated using the three-dimensional (3D) fusion deposition modeling (FDM) technique. FDM is one of the most well-liked low-cost 3D printing techniques for facilitating the adhesion and hot melting of thermoplastic materials. PA6 exhibits an exceptionally significant overall performance in the families of engineering thermoplastic polymer materials. By using twin-screw extrusion, a PA6-GF mixed particles made of PA6 and 20% glass fiber was produced as filament. Based on literature review, the samples have been fabricated for tensile, hardness, and flexural with different layer thickness of 0.08 mm, 0.16 mm, and 0.24 mm, respectively. The composite PA6-GF behavior is characterized through an experimental test employing a variety of test samples made in the x and z axes.

In the field of automobile development, sufficient structure strength is the most basic objective to be accomplished. Typically, method of strength analysis could be divided into static strength and dynamic strength. Analysis of static strength constitutes the major part of the development, but the supplement of dynamic strength is also dispensable to assure structural integrity. This paper presents a methodology about analyzing the impact strength of body structure based on a Multi-body Dynamics (MBD) and Finite Element Analysis (FEA) combined method. Firstly, the full vehicle MBD model consists of Curved Regular Grid (CRG) road model, Flexible Ring Tire (FTire) model and dynamic deflection-force bump stop model was built in Adams/Car. Next, Damage Initiation and Evolution Model (DIEM) failure criteria was adopted to describe material failure behavior.

The origami structures have received increasing attention in recent years due to the high stiffness ratio and lightweight feature. This paper has proposed an origami-based honeycomb structure and investigated the mechanical properties of the structure. The compression response and energy absorption of the structure under quasi-static loading have been investigated experimentally and numerically. The numerical results closely matched the experimental results in terms of the compression force curve and deformation patterns. The effects of different structural parameters on the mechanical response and energy absorption characteristics were analyzed with the validated model. Finally, the comparative results show that the origami-inspired honeycomb structure, which is characterized by rotational folding mode under axial compression, has better performance in terms of mechanical response and energy absorption.

Side doors are pivotal components of any vehicle, not only for their aesthetic and safety aspects but also due to their direct interaction with customers. Therefore, ensuring good structural performance of side doors is crucial, especially under various loading conditions during vehicle use. Among the vital performance criteria for door design, torsional stiffness plays an important role in ensuring an adequate life cycle of door. This paper focuses on investigating the impact of several door structural parameters on the torsional stiffness of side doors. These parameters include the positioning of the latch, the number of door side hinge mounting points on doors (single or double bolt), and the design of door inner panel with or without Tailor Welded Blank (TWB) construction.

The recent surge in platforms like YouTube has facilitated greater access to information for consumers, and vehicles are no exception, so consumers are increasingly demanding of the quality of their vehicles. By the way, the door is composed of glass, moldings, and other parts that consumers can touch directly, and because it is a moving part, many quality issues arise. In particular, the door panel is assembled from all of the above-mentioned parts and thereby necessitates a robust structure. Therefore, this study focuses on the structural stiffness of the door inner panel module mounting area because the door module is closely to the glass raising and lowering, which is intrinsically linked to various quality issues.

The side-door operation of vehicle is vital to the customer, as it reflects the overall build quality of the vehicle. The side door check arm is one of the primary components that determine the operating characteristics of a vehicle door. The profile of the check arm has a significant impact on the closing effort of side doors. In this study, the check arm profiles are analyzed virtually in relation to the side door's closing velocity. A virtual door model was developed in ADAMS to simulate the side door closing and opening. The study involves a check arm that guides the ball spring mechanism housing unit over the guide profile. Typically, a check-arm guide profile has two or three indents at a specific location which serves to maintain the door open in those positions. When a door enters an indent, the user must exert an effort to traverse it. Furthermore, the slope profile of the check arm defines the self-closing assist offered from the initial indent to the latching position.

Alongside advancements in automated vehicle technologies, occupants within vehicle compartments are enjoying increased freedom to relax and enjoy their journeys. For instance, reclined seating postures have become more prevalent and comfortable compared to upright seating when Highly Automated Vehicles (HAVs) are introduced. Unfortunately, most Anthropomorphic Testing Devices (ATD) do not support reclined postures. THOR-AV 50M is a specially designed dummy for reclined postures. As a crucial tool for developing safety restraint systems to protect reclined occupants, the first question is how to position it correctly on a reclined seat before impact testing. In this study, classical zero gravity seats were selected. H-point coordinators of selected seat at 25°, 40° and 60° seatback angle were measured and compared by using H-point machine (HPM) even though current HPM was not designed for reclined seat.

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.

As additive manufacturing continues to establish its position within the automotive sector, there is a need for a comprehensive exploration of the mechanical attributes exhibited by locally sourced filaments. Such investigation is extremely important, as it is intrinsically linked to ensuring the reliability and security of components manufactured through 3D printing. This research delves into an examination of the impact resistance properties demonstrated by 3D-printed specimens, employing filaments from three prominent Brazilian manufacturers. The main objective is to elucidate the suitability and potential applications of these filament materials (Polylactic Acid (PLA), Polyethylene Terephthalate Glycol (PETG), and Acrylonitrile Butadiene Styrene (ABS)) within the field of automotive engineering, thus contributing to the evolving landscape of additive manufacturing within this industry.

Motorcycles which are designed for both regular as well as rough terrains experience more severe vertical impact loads from ground in comparison with motorcycles which travel only on regular terrains. Therefore, drop test is considered an important method to evaluate durability for said vehicles. Fuel Tank mounted over front frame of a motorcycle is the most critical component from safety point of view and hence, need to be analysed for vertical drop load case. To do so, modelling of whole vehicle can be a hectic task and has to be avoided. In the present work, behaviour of fuel tank mounted over frame support and subjected to vertical drop from H(m) height is studied with the help of support excitation method incorporated with explicit non-linear time integration scheme using Finite Element Analysis (FEA) code in commercial FEA software. Through this scheme, effect on Fuel Tank of vehicle drop can be studied without actually modelling the whole vehicle.

There are established federal requirements and industry standards for frontal crash testing of motor vehicles. Consistently applied methods support reliability, repeatability, and comparability of performance metrics between tests and platforms. However, real world collisions are rarely identical to standard test protocols. This study examined the effects of occupant anthropometry and passive restraint deployment timing on occupant kinematics and biomechanical loading in a moderate-severity (approximately 30 kph delta-V) offset frontal crash scenario. An offset, front-to-rear vehicle-to-vehicle crash test was performed, and the dynamics of the vehicle experiencing the frontal collision were replicated in a series of three sled tests. Crash test and sled test vehicle kinematics were comparable. A standard or reduced-weight 50th percentile male Hybrid III ATD (H3-50M) or a standard 5th percentile female Hybrid III ATD (H3-5F) was belted in the driver’s seating position.

Event data recorders (EDRs) were harvested and imaged after Insurance Institute for Highway Safety (IIHS) 56 km/hr frontal and 64.4 km/hr frontal offset crashes of 15 different brands of 2016-2022 vehicles. The speed and delta-V in the EDR were compared to reference instrumentation. Speed data was accurate within the generally accepted range of +/-4%. The 40% overlap tests had generally similar vehicle kinematics, and their delta-Vx data was accurate. However, there was a much greater variance in the small (25%) overlap tests. Some outliers in the small overlap delta-Vx tests required further analysis using overhead video analysis. The video analysis more closely matched the EDR recorded values. These offset tests create significant post-crash rotation, and both EDR and IIHS instrumentation were affected by their location away from the center of gravity. The Y-axis was affected much more than the X-axis.

FMVSS No. 205, “Glazing Materials,” uses impact test methods specified in ANSI/SAE Z26.1-1996. NHTSA’s Vehicle Research and Test Center initiated research to evaluate a subset of test methods from ANSI Z26.1-1996 including the 227 gram ball and shot bag impact tests, and the fracture test. Additional research was completed to learn about potential changes to tempered glass strength due to the ceramic paint area (CPA), and to compare the performance of twelve by twelve inch flat samples and full-size production parts. Glass evaluated included tempered rear quarter, sunroof, and backlight glazing. Samples with a paint edge were compared to samples without paint, and to production parts with and without paint in equivalent impact tests. A modified shot bag with stiffened sidewalls was compared to the ANSI standard shot bag. The fracture test comparison included evaluating the ANSI Z26.1 impact location and ECE R43 impact location.

A and B stiffness coefficients to model the frontal stiffness of vehicles is a commonly used and accepted technique within the field of collision reconstruction. Methods for calculating stiffness coefficients rely upon examining the residual crush of a vehicle involved in a crash test. When vehicles are involved in a collision, portions of the crushed vehicle structures rebound from their maximum dynamic crush position. Once the vehicle structures have finished rebounding, the remaining damage is called the residual crush. A problem can arise when the plastic bumper cover rebounds more than the vehicle's structural components, resulting in an air gap between the structural components and the plastic bumper cover. Most modern New Car Assessment Program (NCAP) tests quantify crush in the test reports based on the deformed location of the plastic bumper cover and not the structural components behind the plastic bumper cover. This results in an underreporting of the actual residual crush.

In day-to-day life, accidents do occur frequently all around the globe. It is difficult to prevent these accidents as they occur due to different reasons, which cannot be easily controlled. However, the fatal injuries occurring to passengers can be reduced by installing efficient safety systems in vehicles, which will help in saving the lives of mankind. Many safety systems are being installed in vehicles such as seat belt restraints, airbags, etc. Generally, three-point seat belts are installed in passenger vehicles for safety purposes. This type of seat belt doesn't arrest the entire motion of the occupant's body during vehicle crashes, which can lead to fatal injuries and sometimes even death during vehicle crashes. To buckle passengers with seats, we can use five-point seat belts which will help in mitigating the injuries as compared to three-point seat belts.

Metal Matrix Composites (MMC) made of the aluminium as base metal is now being used in diversed applications due to its extended properties. The physical, chemical, mechanical and structural properties make it as irresistible in the engineering applications. Metal Matrix Composites (MMCs) based on aluminium have increased in popular in various applications including aerospace, car, space, transportation, and undersea applications.. In this study, Al LM25/SiCp MMC was fabricated using a low-cost stir casting technique, and the weight percentage of SiCp was varied from 4% to 8% to prepare the MMC plates. The aim of the research was to investigate the mechanical properties of the specimen, including hardness, tensile, and impact tests. The microstructure of the specimens is investigated which shows the bonding between the particles which is fabricated by Stir casting method. The sample 2 has better mechanical properties when it is compared with other specimens.