Browse Topic: Restraint systems

Items (2,658)
ABSTRACT Non-combat tactical vehicle incidents such as rollover are one of the major causes of soldier injuries and deaths. Rollover incidents are usually associated with multiple impacts which result in complex interactions between occupants and hard structural components. Detailed information of occupant responses in such rollover incidents are lacking, and to design effective occupant protection system and safety restraints systems, understanding the vehicle to occupant interaction is essential. The performance of ground vehicles during a rollover event is an important safety and occupant protection requirement for military vehicles. Modeling and simulation are a very useful tool in study and investigation of vehicle rollover characteristics and countermeasure concepts. The main goal of this research is to develop an M&S model of a HMMWV full vehicle system and evaluate the effectiveness of the different restraints systems in a lateral 25 mph rollover tests and its effect on
Babu, VenkateshKang, JianKankanalapalli, SanjaySheng, JimVunnam, MadanKarwaczynski, Sebastian K.Jessup, ChrisDuncan, Mike
ABSTRACT The objective of this study is to understand the occupant kinematics and injury risks in a light tactical vehicle under frontal crash conditions using a combination of physical tests and computer simulations. A total of 20 sled tests were conducted in a representative environment to understand occupant kinematics, and quantify the effects from occupant body size (5th/50th/95th), military gear (helmet/vest/varying gear configurations), seatbelt type (5point/3point), and advanced seatbelt features (pre-tensioner/load limiter) on occupant kinematics and injury risks in frontal crashes. These tests have been used to validate a set of finite element (FE) models of occupants, gear, and restraints. Kinematics exhibited often included submarining due to the lack of knee bolster and the added weight from the military gear. Body size, seatbelt type, and advanced belt features also showed significant effects on occupant kinematics
Hu, JingwenWood, LaurenOrton, NicholeChen, CongRupp, JonathanReed, MatthewGruber, RebekahScherer, Risa
ABSTRACT The objective of this study was to optimize the occupant restraint systems (including both seatbelt and airbag) in a light tactical vehicle under frontal crash conditions through a combination of sled testing and computational modeling. Two iterations of computational modeling and sled testing were performed to find the optimal restraint design solutions for protecting occupants represented by three size of ATDs (namely Hybrid-III 5th percentile female ATD, 50th percentile male ATD, and 95th male ATD) and two military gear configurations, namely improved outer tactical vest (IOTV) and SAW Gunner configuration using a tactical assault panel (TAP). The sled tests with the optimized seatbelt and airbag designs provided significant improvement on the head, neck, chest, and femur injury risks compared to the baseline tests. This study demonstrated the benefit of adding a properly designed airbag and advanced seatbelt to improve the occupant protection in frontal crashes for a light
Hu, JingwenOrton, NicholeChen, CongRupp, Jonathan D.Reed, Matthew P.Gruber, RebekahScherer, Risa
With the capability of predicting detailed injury of occupants, the Human Body Model (HBM) was used to identify potential injuries for occupants in car impact events. However, there are few publications on using HBM in the aviation industry. This study aims to investigate and compare the head, neck, lumbar spine and thoracic responses of the Hybrid III and the THUMS (Total Human Model for Safety) model in the horizontal 26g and vertical 19g sled tests required by the General Aviation Aircraft Airworthiness Regulations. The HIC of THUMS and Hybrid III did not exceed the requirements of airworthiness regulations. Still, THUMS had higher intracranial pressures and intracranial stresses, which could result in brain injury to the occupants. In vertical impact, the highest stress of the neck of THUMS appears at the cervical spine C2 and the upper neck is easily injured; in horizontal impact, the cervical spine C7 has the highest load, and the lower neck is easily injured. Due to the low
Shi, XiaopengDing, XiangheGuo, KaiLiu, TianfuXie, Jiang
ABSTRACT A process for donning restraints did not exist as related to Soldier gear encumbrance. For laboratory testing restraint donning was left to the discretion of the technician or test engineer setting up the Anthropomorphic Test Dummy (ATD) and resulted in increased occupant excursion. Therefore the Ground System Survivability (GSS) Blast Mitigation Team (BMT), United States Army Tank Automotive Research, Development and Engineering Center (TARDEC), Warren, MI. conducted studies which were accomplished through restraint system testing. This testing consisted of both Blast and Crash test modes. It was discovered that the ideal testing method couples the occupant to the seat and reduces the amount of restraint to gear interaction. When properly donned the occupant experiences reduced amounts of excursion vs. the improperly restrained occupant. This resulted in a procedure for which restraint systems are to be donned for test events. The routing procedure is included in this
Karwaczynski, Sebastian K.
ABSTRACT The performance of ground vehicles during a rollover event is an important safety and occupant protection requirement for military vehicles. Modeling and simulation is a very useful tool in study and investigation of vehicle rollover characteristics and countermeasure concepts. This study presents two methods of simulating the rollover events. The first one uses Full System Method (FSM), where all the components are modelled as is and are evaluated. The second method is a reduced order modelling method (ROMM) using integration of the resulted kinematics data from FSM into the vehicle model with occupant & restraints. The FSM & ROMM methods were applied to simulate two HMMMV rollover events, and the results from both methods show that simulation and test data agreed fairly well. Computational time reduced by the ROMM was about 53% of that of the FSM. ROMM approach not only saves significant computational time but also increases robustness of the simulation. Citation: V. Babu, J
Babu, V.Kang, J.Kankanalapalli, S.Sheng, J.Vunnam, M.Karwaczynski, S. K.Jessup, C.Duncan, M.Paulson, K.
ABSTRACT In order to reduce the frequency and severity of warfighter head, neck, and spine injuries associated with military vehicle underbody IED and AVL blasts, crash, and rollover, Hy-Tek Manufacturing Co. Inc. (HMC) has designed, fabricated, tested, and optimized its Vehicle Roof Inflatable Impact Bladder (VRIIB). Comprised of two (2) thin and impermeable airbags separated by semi-rigid force distribution plates; the VRIIB is designed to be mounted on the interior roof panel of military combat vehicles in a deflated state. During IED or AVL detonation, the VRIIB inflates by means of a COTS airbag inflator to provide a significant reduction in the rate at which a warfighter’s head or neck decelerates against the rigid vehicle roof panel. The VRIIB is designed to remain inflated and functional for a protracted period of time after its initial actuation in order to protect vehicle mounted warfighters from follow-on blast related roof impacts, subsequent vehicle rollover and/or vehicle
Middlebrook, DonaldJude, JohnPeck, Jason
ABSTRACT Seatbelt-mounted airbag is a new type of occupant restraint system, in which the airbag is integrated into the seatbelt and hence can be easily and quickly implemented into the current tactical vehicles without significant vehicle structure or interior changes. The objective of this study was to develop, optimize, and demonstrate seatbelt-mounted airbag designs for reducing occupant injury risks in a light tactical vehicle under frontal crashes. A total of 19 sled tests and over 30 FE simulations were performed to find the optimal seatbelt-mounted airbag designs for protecting occupants represented by three sizes of ATDs and two military gear configurations. Various lap-belt-mounted airbag and shoulder-belt-mounted airbag designs were evaluated for driver, front-seat passenger, and rear-seat passenger locations in a tactical vehicle. The test and simulation results showed that the optimized designs substantially reduced the occupant injury risks to the head, neck, and chest
Hu, JingwenOrton, NicholeBoyle, KyleAshok, NikhilKlima, JulieStaniak, CeliaScherer, RisaReed, Matthew
ABSTRACT This paper focuses on the application of a novel Additive Molding™ process in the design optimization of a combat vehicle driver’s seat structure. Additive Molding™ is a novel manufacturing process that combines three-dimensional design flexibility of additive manufacturing with a high-volume production rate compression molding process. By combining the lightweighting benefits of topology optimization with the high strength and stiffness of tailored continuous carbon fiber reinforcements, the result is an optimized structure that is lighter than both topology-optimized metal additive manufacturing and traditional composites manufacturing. In this work, a combat vehicle driver’s seatback structure was optimized to evaluate the weight savings when converting the design from a baseline aluminum seat structure to a carbon fiber / polycarbonate structure. The design was optimized to account for mobility loads and a 95-percentile male soldier, and the result was a reduction in
Hart, Robert JPerkins, J. ScottBlinzler, BrinaMiller, PatrickShen, YangDeo, Ankit
Pelvic orientation in vehicles is crucial for preventing injuries and creating safer vehicles and restraint systems. A better understanding of pelvic orientation could provide more accurate anthropomorphic test device (ATD) models of underrepresented populations such as obese individuals, children, and small females. Sonomicrometry is the use of piezoelectric transducers that transmit ultrasound signals to each other to measure the distance between them. These signals may be aggregated using triangulation. In this experiment, ultrasound crystals were secured to the surface of a porcine surrogate to evaluate pelvic movement. This data was then processed using Sonometrics software to generate a 3D model of four static positions and three dynamic tests. The test was validated using a camera and a 3D measurement arm (CMM) to validate XYZ positions. This article discusses how this method could be helpful for developing more accurate ATD models, preventing fatalities in vehicle crashes
Mrozek, AllisonSirhan, KaterenaMacDonald, RobertDannaoui, AbdulMazloum, AishaOchocki, Katarzyna‘Dale’ Bass , Cameron R.
Drop tower testing was conducted using 50th percentile male PMHS at 15G peak acceleration in a rigid seat, with a seat pan-to-seatback angle of 90°. Subjects were instrumented with 6DOF motion blocks at T1, T4, T12, L3, and S1 to capture detailed vertebral body kinematics. Pressure sensors were also placed throughout the lumbar spine to estimate force in the intervertebral discs from S1-L2. PMHS were restrained using a pilot torso harness attached to the seat at the shoulders and lap belt, both pretensioned to 89 N. Reaction forces were measured in the seat using six-axis loads under the seat pan. Final positioning of the occupant was documented using a FARO arm point probe and laser scanner. To recreate the experimental setup, CAD models of the experimental fixture were meshed using a commercial FE modeling software (Hypermesh) and imported into LS-Dyna for incorporation with the THUMS model. The belt routing tool in LS-PrePost v4.9.12 was used to develop the torso harness and
DeWitt, Timothy R.Marcallini, Angelo M.Bolte IV, John H.Kang, Yun-Seok
Extreme out-of-position pre-crash postures may need high-force pre-pretensioner (PPT) for effective repositioning (Mishra et al., 2023). To avoid applying a high force on the chest, we hypothesized that in case of these extreme postures the PPT may be activated in the absence of a pre-crash motion as a cautionary measure. Therefore, the aims of this study were: (1) to understand the effect of the PPT in repositioning a forward-leaning occupant in static conditions and (2) to characterize occupants’ kinematic variability during repositioning. Sixteen healthy volunteers (8 males, 8 females, 23.8 ± 4.2 years old) were seated with a 40° forward posture on a vehicle seat and restrained with a 3-point seat belt equipped with a PPT. Two PPT seatbelt conditions were examined: low PPT (100 N) and high PPT (300 N). Head and trunk rearward displacements relative to the initial forward-leaning position at 350 ms from PPT onset were collected with a 3D motion-capture system and compared between
Witmer, MaitlandGriffith, MadelineGraci, Valentina
This study compared modern vehicle and booster geometries with relevant child anthropometries. Vehicle geometries (seat length, seat pan height, shoulder belt outlet height, and roof height) were obtained for 275 center and outboard rear seating positions of US vehicles (MY 2009–2022). Measurements of 85 US boosters (pan height and pan length) and anthropometries of 80 US children between 4–14yo (seated height, thigh length, leg length, and seated shoulder height) were also collected. Comparisons were made between vehicles, boosters, and child anthropometries. Average vehicle seat lengths exceeded child thigh lengths (+9.5cm). Only 16.4% of seating positions had seat lengths less than the child thigh length mean+1SD. Even for children at least 145cm, only 18.8% had thigh lengths greater than the average vehicle seat length. Child thigh lengths were more comparable with average booster seat pan lengths for all multi-mode and high-back designs (-2.0cm) and low-back boosters (+3.1cm). The
Baker, Gretchen H.Connell, Rosalie R.Rhodes, Carrie A.Mansfield, Julie A.
The primary purpose of the active safety feature is to reduce the danger of a collision between the car and an obstruction. To improve occupant safety, active safety systems must be included on all new vehicles; nonetheless, not all incidents are preventable. The frequency of incidents on the road has recently increased in tandem with the number of cars, making it critical to investigate the crashworthiness of a vehicle because human life is at the top of the priority list. This study examines an occupant's responses prior to a crash event, as well as studies into how occupant posture influences injury data. Most of the existing research focuses on the pre-crash event or the occupant's optimal seated position. However, it is critical to understand an occupant's reflex or behavior during the pre-crash event, when the occupant is typically not in an appropriate seating posture due to the panic reflex. As a result, an occupant's reflex in a panic situation will change their seating
Shankara Murthy, SantoshSrinivasa, PraveenCK, UmeshPatil, ShubhamJois, Rahul
Forward-facing child restraint systems (FF CRS) and high-back boosters often contact the vehicle seat head restraint (HR) when installed, creating a gap between the back surface of the CRS and the vehicle seat. The effects of HR interference on dynamic CRS performance are not well documented. The objective of this study is to quantify the effects of HR interference for FF CRS and high-back boosters in frontal and far-side impacts. Production vehicle seats with prominent, removeable HRs were attached to a sled buck. One FF CRS and two booster models were tested with the HR in place (causing interference) and with the HR removed (no interference). A variety of installation methods were examined for the FF CRS. A total of twenty-four tests were run. In frontal impacts, HR interference produced small but consistent increases in frontal head excursion and HIC36. Head excursions were more directly related to the more forward initial position rather than kinematic differences caused by HR
Mansfield, Julie A.
The descent phase of Indian Manned Space Mission culminates with a crew module impacting at a predetermined site in Indian waters. During water impact, huge loads are experienced by astronauts. This demands an impact attenuation system which can attenuate the impact loads and reduce the acceleration experienced by astronauts to safe levels. Current state of the art impact attenuation systems uses honeycomb core, which is passive and can only be used once (at touchdown impact) during the entire mission. Active and reusable attenuation systems for crew modules are still an unexplored territory. Three configurations of impact attenuators are selected for this study for the crew module configuration, namely, hydraulic damper, hydro-pneumatic damper and airbag systems. All the subsystems are mathematically modelled, and initial sizes are estimated using Genetic Algorithm and SQP optimization techniques. Semi-active control for Hydraulic and Hydro-Pneumatic dampers are implemented and
Avirah, Nohin KLakshman, Dasu Deva KarthikPotnuru, Sai SanthoshPramod, Athul PKurian, Sabin
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. The Accelerative Loading Fixture (ALF) version 2, located at APG’s Bear Point range
Pietsch, HollieCristino, DanielleDanelson, KerryBolte, JohnMason, MatthewKemper, AndrewCavanaugh, JohnHardy, Warren
The on-board emergency call system with accurate occupant injury prediction can help rescuers deliver more targeted traffic accident rescue and save more lives. We use machine learning methods to establish, train, and validate a number of classification models that can predict occupant injuries (by determining whether the MAIS (Maximum Abbreviated Injury Scale) level is greater than 2) based on crash data, and ranked the correlation of some factors affecting vehicle occupant injury levels in accidents. The optimal model was selected by the model prediction accuracy, and the Grid Search method was used to optimize the hyper-parameters for the model. The model is based on 2799 two-vehicle collision accident data from NHTSA CISS (The Crash Investigation Sampling System of NHTSA) traffic accident database.The results show that the model achieves high-precision prediction of occupant injury MAIS level (recall rate 0.8718, AUC(Area under Curve) 0.8579) without excluding vehicle model, and
Huida, ZhangLiu, YuRui, YangWu, XiaofanFan, TiqiangWan, Xinming
In 2021, 412,432 road accidents were reported in India, resulting in 153,972 deaths and 384,448 injuries. India has the highest number of road fatalities, accounting for 11% of the global road fatalities. Therefore, it is important to explore the underlying causes of accidents on Indian roads. The objective of this study is to identify the factors inherent in accidents in India using clustering analysis based on self-organizing maps (SOM). It also attempts to recommend some countermeasures based on the identified factors. The study used Indian accident data collected by members of ICAT-ADAC (International Centre for Automotive Technology - Accident Data Analysis Centre) under the ICAT-RNTBCI joint project approved by the Ministry of Heavy Industries, Government of India. 210 cases were collected from the National Highway between Jaipur and Gurgaon and 239 cases from urban and semi-urban roads around Chennai were used for the analysis. Based on this study, the following results were
Vimalathithan, KulothunganRao K M, PraneshVallabhaneni, PratapnaiduSelvarathinam, VivekrajManoharan, JeyabharathPal, ChinmoyPadhy, SitikanthaJoshi, Madhusudan
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. In the crash test
Courtney, AmyCrosby, CharlesMiller, BruceOsterhout, AaronWalker, JamesGondek, Jonathon
In 1983, a seat belt use rate survey was published in which 9% shoulder belt use was observed for front-outboard passengers. Nearly forty years later the national estimate of seat belt use has achieved a record high of 91.6% belt use by adult front-seat passengers in 2022. In contrast, there have been very few studies conducted in order to determine seat belt use within large buses and motorcoaches. In 2013, the NHTSA published a final rule amending FMVSS 208 to require seat belts for each seating position in all new over-the-road buses. Beginning in 2016, newly manufactured buses were required to be equipped with lap and shoulder belts for each driver and passenger seat. Recent studies have reported that seat belt use on motorcoaches with relatively long routes was only 2.6%. Similarly, seat belt use in airport shuttle buses was reported to be only 1%. The present observational study was conducted to determine an updated seat belt usage rate of passengers on airport shuttle buses. The
Gregg, Richard H.
Background: The Indian automobile industry, including the auto component industry, is a significant part of the country’s economy and has experienced growth over the years. India is now the world’s 3rd largest passenger car market and the world’s second-largest two-wheeler market. Along with the boon, the bane of road accident fatalities is also a reality that needs urgent attention, as per a study titled ‘Estimation of Socio-Economic Loss due to Road Traffic Accidents in India’, the socio-economic loss due to road accidents is estimated to be around 0.55% to 1.35% of India’s GDP [27] Ministry of road transport and highways (MoRTH) accident data shows that the total number of fatalities on the road are the highest (in number terms) in the world. Though passenger car occupant fatalities have decreased over the years, the fatalities of vulnerable road users are showing an increasing trend. India has committed to reduce road fatalities by 50% by 2030. In this context, the automotive
Mehta, PoojaPrasad, AvinashSrivastava, AakashArora, PankajHowlader, Ashim
Occupant protection in side impacts, in particular for near-side occupants, is a challenge due to the occupant’s close proximity to the impact. Near-side occupants have limited space to ride down the impact. Curtain and side airbags fill the gap between occupant and the side interior. This analysis was conducted to provide insight on the characteristics of side impacts and the relevancy of currently regulated test configurations. For this purpose, 2007-2015 NASS-CDS and 2017-2021 CISS side crash data were analyzed for towed light vehicles. 2008 and newer model year vehicle data was selected to ensure that most vehicles were equipped with side/curtain airbags. The results showed that side impacts accounted for approximately 26.7% of the vehicles involved and 18.9% of the vehicles with at least one seriously injured occupant. Most side impacts involved damage to the front and front-to-center of the vehicle. For seriously injured (MAIS 3+F) occupants, impacts to the occupant compartment
Parenteau, ChantalAult, B. NicholasToomey, DanielKrishnaswami, RamBurnett, Roger
The head injury mechanisms of occupants in traffic accidents will be more complicated due to the diversified seating postures in autonomous driving environments. The injury risks and assessment parameters in complex collision conditions need to be investigated thoroughly. Mining the simulation data by the support vector machine (SVM) and the random forest algorithms, some head injury predictive models for a 6-year-old child occupant under a frontal 100% overlap rigid barrier crash scenario were developed. In these head injury predictive models, the impact speed and sitting posture of the occupant were considered as the input variables. All of these head injury predictive models were validated to have good regression and reliability (R2>0.93) by the ten-fold cross-validation. When the collision speed is less than 60km/h, rotational load is the primary factor leading to head injury, and the trends of BrIC, von Mise stress, Maxshear stress, and MPS are similar. However, when the speed
Li, HaiyanWang, YanxinHe, LijuanLv, WenleCui, ShihaiRuan, Jesse Shijie
The Advanced Driver Assistance System (ADAS) is a comprehensive feature set designed to aid a driver in avoiding or reducing the severity of collisions while operating the vehicle within specified conditions. In General Motors (GM) vehicles, the primary controller for the ADAS is the Active Safety Control Module (ASCM). In the 2013 model year, GM introduced an ASCM utilizing the GM internal nomenclature of External Object Calculation Module (EOCM) in some of their vehicles produced for the North American market. Similar to the Sensing and Diagnostic Module (SDM) utilized in the restraints system, the EOCM3 LC contains an Event Data Recorder (EDR) function to capture and record information surrounding certain ADAS or Supplemental Inflatable Restraint (SIR) events. The ASCM EDR contains information from external object sensors, various chassis and powertrain control modules, and internally calculated data. This event data includes date and time, GPS location, driver inputs and vehicle
Bare, CleveSkiera, JasonSmyth, BrianBeetham, TommyFloyd, DonaldKoo, WinstonNewell, Devin
In this study, an optimized structure for opening the headlining considering the deployment of the face-to-face roof airbag was studied. It was confirmed that the deployment performance differs depending on the skin of the headlining, and a standardized structure with mass production was proposed. Non-woven fabric and Tricot skin, which are economical and high-end specifications, satisfy the performance of PVC fusion application specifications after cutting 80% of the skin. The structure that satisfies the entire body including the knit specifications is a type that separates the roof airbag area piece, the corresponding soft piece is separated, and the deployment performance is satisfied with safety. Therefore, the structure is proposed as a standardized structure. This structure is expected to be applicable to roof DAB (Driver Airbag), PAB (Passenger Airbag), and Sunroof Airbag, which will be necessary technologies to secure indoor space. Regardless of which area the airbag will be
Park, Jiseob
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. Additionally, three CRS models with load legs were installed into 42 vehicle seating positions each (n=126
Mansfield, Julie
Determining occupant kinematics in a vehicle crash is essential when understanding injury mechanisms and assessing restraint performance. Identifying contact marks is key to the process. This study was conducted to assess the ability to photodocument the various fluids on different vehicle interior component types and colors with and without the use of ultraviolet (UV) lights. Biological (blood, saliva, sweat and skin), consumable and chemical fluids were applied to vehicle interior components, such as seatbelt webbing, seat and airbag fabrics, roof liner and leather steering wheel. The samples were photodocumented with natural light and UV light (365 nm) exposure immediately after surface application and again 14 days later. The review of the photos indicated that fabric type and color were important factors. The fluids deposits were better visualized on non-porous than porous materials. For example, blood was better documented on curtain airbags than side or driver airbags. Blood and
Boysen, KevinParenteau, ChantalToomey, DanielGregg, Richard H.
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. THOR-AV 50M with loosened joints, served to simulate human relaxation fully when
Liu, ChongqingWang, Zhenwen
The handling of flexible components creates a unique problem set for pick and place automation within automotive production processes. Fabrics and woven textiles are examples of flexible components used in car interiors, for air bags, as liners and in carbon-fiber layups. These textiles differ greatly in geometry, featuring complex shapes and internal slits with varying material properties such as drape characteristics, crimp resistance, friction, and fiber weave. Being inherently flexible and deformable makes these materials difficult to handle with traditional rigid grippers. Current solutions employ adhesive, needle-based, and suction strategies, yet these systems prove a higher risk of leaving residue on the material, damaging the weave, or requiring complex assemblies. Pincer-style grippers are suitable for rigid components and offer strong gripping forces, yet inadvertently may damage the fabric, and introduce wrinkles / folded-over edges during the release process. Non-planar
Strelkova, DoraUrbanic, Ruth Jill
Predicting airbag deployment geometries is an important task for airbag and vehicle designers to meet safety standards based on biomechanical injury risk functions. This prediction is also an extraordinarily complex problem given the number of disciplines and their interactions. State-of-the-art airbag deployment geometry simulations (including time history) entail large, computationally expensive numerical methods such as finite element analysis (FEA) and computational fluid dynamics (CFD), among others. This complexity results in exceptionally large simulation times, making thorough exploration of the design space prohibitive. This paper proposes new parametric simulation models which drastically accelerate airbag deployment geometry predictions while maintaining the accuracy of the airbag deployment geometry at reasonable levels; these models, called herein machine learning (ML)-accelerated models, blend physical system modes with data-driven techniques to accomplish fast
Valenzuela del Rio, Jose E.Lancashire, RichardChatrath, KaranRitmeijer, PeterArvanitis, ElenaMirabella, Lucia
To harmonize and define terminology associated with occupant protection for children for vehicle manufacturers and child restraint manufacturers in the United States and Canada
Children's Restraint Systems Committee
The objective of this study was to quantify the field performance of passenger vehicle event data recorders (EDRs) in recording data into non-volatile memory at the 8 km/h delta-v (Δv) trigger threshold specified by Title 49, Part 563 of the Code of Federal Regulations (Part 563). Part 563 applies to passenger vehicles manufactured on or after September 1, 2012. The trigger threshold is distinct from the threshold required to deploy an airbag. Events meeting the trigger threshold will cause data to be preserved on the EDR even if airbags are not deployed. This is the first study to quantify EDR trigger threshold performance. This data is valuable in the evaluation of sub-airbag deployment crashes. The study was accomplished via analysis of EDR and reconstructed Δv data from 3,960 cases in the Crash Investigation Sampling System (CISS) database maintained by the National Highway Traffic Safety Administration (NHTSA). The binary presence or non-presence of an event on the EDRs of
Watson, Richard A.Bonugli, EnriqueGreenston, MathewSantos, ErickMartinez, Jonathan
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. In this paper, we evaluate the performance of five-point seat belts on occupant safety during vehicle crashes on flat rigid
Vinodh, T.Dineshkumar, C.Jeyakumar, P.D.Muthiya, Solomon JenorisVinayagam, Nadana KumarChristu Paul, R.Dhanraj, Joshuva Arockia
Reducing material wherever there is a possibility in automobile industry is inevitable for weight and cost saving. This paper explains about the possibilities of optimizing the material composition of automotive Headliners (also called as Roof liners) without affecting the performance and safety criteria. In this paper, we are targeting at optimizing the individual constituents of a composite Headliner. A conventional Headliner comprises of many sandwich layers of which PU foam shares the major percentage of the composition contributing to 80% of the Headliner thickness. In this paper, we are discussing about the optimization done in Headliner sandwich constituents without affecting the core performance parameters of headliner such as curtain airbag deployment, ergonomic regulations, drop test etc. By incorporating this change, without significant changes in other layers, overall weight reduction of ~24% and overall cost reduction of ~24% is achieved
D, GowthamVadla, VilasBhaskararao, PathivadaSai, KonduruBornare, HarshadRitesh, KakadeDeoli, ManishKakani, Phani Kumar
Bus transport is an important element in a sustainable transport strategy. The objective of this study is to understand crashes and injuries involving buses, suggest potential passive-safety interventions, estimate their effectiveness, and compare their effectiveness between Germany and India. Descriptive analysis of crash data from the German In-depth Accident Study (GIDAS) and the Road Accident Sampling System India (RASSI) database was performed in two parts: First, bus passengers and their injuries were analyzed and second, pedestrian injuries in bus-to-pedestrian crashes were analyzed. Lastly, interventions were suggested, and their effectiveness was estimated. Analysis of bus passengers showed that most moderate-to-critical injuries in the GIDAS data were to the head caused by interior bus components. In the RASSI data, head injuries were also frequent, often due to bus interior contact, but also due to ejection and impact to the ground or bus exterior. As many as 31% of all
Ranmal, AartiJeppsson, HannaStrandroth, JohanLubbe, Nils
Government of India, in 2017, mandated a Side Impact Test (AIS 099 technically aligned to UN ECE Regulation No. 95.03 series of amendments) on M1 category Passenger Vehicles to ensure protection of occupants in lateral impact accident scenarios. Later, in 2022, a draft notification has been issued by the Government mandating installation of 6 airbags (2 Nos of thorax side airbags, 2 Nos of head protection or curtain airbags in addition to already mandated installation of Driver and Passenger Airbags) in all such passenger vehicles. However, the vehicles fitted with side thorax airbag and curtain airbags are proposed to be assessed as per AIS099 test only. Curtain Airbags are typically installed to protect occupant’s head from severe injuries in narrow object impacts simulated in Pole Side Impact Test Configurations. However, at present, India has not notified an equivalent standard to UN R135 demanding performance of the vehicle in pole side impact scenarios. Typically, OEMs may need
Jaju, DivyanKulkarni, DileepMahindrakar, RahulMahajan, Rahul
Restraint systems in automotives are inevitable for the safety of passengers. Curtain airbag is one such restraint system in automotives that reduces the risk of injury to passengers during crash, without which head injury is inevitable during side crash of a vehicle. So successful deployment of curtain airbag (henceforth called as CAB) is very important in automotive safety during crash. This paper dwells about the optimization done in ramp bracket angle with successful deployment of curtain airbag. This optimization has paved the way for increasing the head-roominess by ~15% and to respect the safety and styling intent in the vehicle successfully. Providing a ramp bracket at the lower bottom side of CAB guides the airbag successfully during deployment. Ramp bracket angle plays a vital role in guiding the airbag inside the passenger’s cabin without any obstruction. This paper challenges the conventional ramp bracket angle followed for CAB deployment with an alternate angle and has
D, GowthamL, DharshanBornare, HarshadRitesh, KakadeDeoli, ManishBhaskararao, PathivadaGangapuram, SureshKakani, Phani Kumar
As we all know, automotive headliners are an essential component of any car’s interior as they cover all the internal components and provide a clean and finished look. Headliners not only increase the aesthetic appeal of a car’s interior, but also acts as an insulation and sound absorption source. As per the latest Government norms, Curtain Airbag (henceforth called as CAB) has been made mandatory and this change calls for the corresponding changes in the Headliner packaging of all passenger vehicles. In general, curtain air-bag deployment calls for a twist open of Headliner at lateral sides (a portion below Hinge-line) during the deployment. This enables the inflated airbag to flow inside the passenger cabin to protect the passenger from any injury. Conventionally no components are packaged below the hinge-line area of headliner to avoid obstruction for CAB deployment and any part fly-off concerns. For this reason, no foams/components are kept below the hinge-line region of the
D, GowthamL, DharshanBornare, HarshadRitesh, KakadeDeoli, ManishVadla, VilasKakani, Phani Kumar
Airbags are crucial elements of passive safety in vehicles that help minimizing occupant injuries during various crash scenarios such as frontal, side, and oblique impacts. Airbags in cars are now mandatory in many countries, and their performance depends on how well the system is designed. A well-tuned airbag deployment algorithm is necessary to score superior NCAP safety ratings. Tuning of airbag deployment algorithms requires several data points which are obtained through actual crash testing. This is a cumbersome and expensive process as it involves crash tests for each scenario (e.g., full front barrier, offset deformable barrier, angled impact, etc.) at multiple test speeds. These tests are destructive and render the vehicles only worthy of scrap. The data gathered from various sensors (acceleration, pressure, etc.) is used to develop robust vehicle model specific algorithms that must correctly identify the crash scenario and send airbag firing signal at the optimal pre-decided
Kumar, Ayush
Restraint systems in automotives are inevitable for the safety of passengers. Seat belts are one such restraint system in automotives that prevent drivers and passengers from being injured during a crash by restraining them back. Seatbelt on automotives has interface with Body-in-white (henceforth called as BIW) and Trim parts in-order to serve its purpose at vehicle level. One such interface part of seat belt is the web guide, which assists and ensures the nylon web’s smooth motion at different seat track positions. Web-guides on automotives ensure the flawless motion of seat belt web at pillar trim areas. In this paper, we are discussing alternate ways of assisting the seat belt web without the web-guide as a separate part. In-order to assist and ensure the motion of nylon web in its trajectory, we have extended the flange of the pillar trim involved. The paper throws light on the advantages of using an extended trim flange as web-guide for seat belt web instead of a separate web
D, GowthamBornare, HarshadGangapuram, SureshDeoli, ManishRitesh, KakadeSai, KonduruKakani, Phani Kumar
The passive safety performance of a child seat is modulated by the design features of the child seat and the vehicle interior. For example, in the rear-facing configuration, the child seat impacting front structures increases the head injury risk during a frontal crash. Therefore, this study evaluates the effectiveness of the load leg countermeasure in improving the child seat's overall kinematics and its capability to prevent the secondary impact on the vehicle interior structure in a severe frontal crash scenario. An in-depth, real-world crash investigation involving a properly installed rear-facing child seat impacting the center console was selected for the study where the infant sustained a severe brain injury. In addition, this crash is employed to choose the crash parameters for evaluating the effectiveness of the load leg countermeasure in a similar scenario. Finally, crash sled tests are conducted using the crash signature of the vehicle as obtained from the NHTSA NCAP rigid
Thorbole, Chandrashekhar
This specification establishes the performance and validation requirements for the inflator assembly used in airbag modules
USCAR
SS304 is a type of stainless steel that is well-known for its high ductility and resistance to corrosion; as a result, it is typically utilized in a variety of applications, such as the exhaust systems of automobiles and the springs that are used in seatbelts. Because of its qualities, it will eventually be employed in a variety of body parts, including fuel tanks and chassis, among other things. Due to its properties, SS304 is known to be incredibly difficult to machine using conventional methods. Through a wire electrical discharge machining process, it is easier to cut complex materials with high surface finishes. In this study, a study was conducted on the WEDM process parameters of SS304 to optimize its machining process. The study was carried out using the DoE approach, which involved planning the various experiments. The parameters of the process, such as the pulse on time, peak current, and off time, were analyzed to determine their performance. The various performance measures
Natarajan, ManikandanPasupuleti, ThejasreeKatta, Lakshmi NarasimhamuSomsole, Lakshmi NarayanaD, PalanisamyKiruthika, Jothi
Pre-crash vehicle maneuvers are known to affect occupant posture and kinematics, which consequently may influence injury risks during a collision. In this study, the influence of pre-crash vehicle maneuvers on the injury risks of front-seated occupants during a frontal crash was numerically evaluated. A generic buck vehicle model was developed based on a publicly available FE model, which included the vehicle interior and the front passenger airbag (PAB). The pre-crash phase was simulated using specific rigid-body human models with active joints (GHBMCsi-pre models) developed based on exterior shapes of the simplified deformable human model (GHBMCsi) representing a 50th male subject. Two pre-crash maneuvers representing (1) a generic 1g braking and (2) turning-and-braking scenarios were simulated. Then, the kinematics data of belted GHBMCsi-pre models were transferred using a developed switch algorithm to the corresponding GHBMCsi models, which can predict occupant injury risks
Dahiya, AkshayUntaroiu, Costin
Letter from the Special Issue Editors
Mueller, BeckyBautsch, BrianMansfield, Julie
Objective: This study aimed to optimize restraint systems and improve safety equity by using parametric human body models (HBMs) and vehicle models accounting for variations in occupant size and shape as well as vehicle type. Methodology: A diverse set of finite element (FE) HBMs were developed by morphing the GHBMC midsize male simplified model into statistically predicted skeleton and body shape geometries with varied age, stature, and body mass index (BMI). A parametric vehicle model was equipped with driver, front passenger, knee, and curtain airbags along with seat belts with pretensioner(s) and load limiter and has been validated against US-NCAP results from four vehicles (Corolla, Accord, RAV4, F150). Ten student groups were formed for this study, and each group picked a vehicle model, occupant side (driver vs. passenger), and an occupant model among the 60 HBMs. About 200 frontal crash simulations were performed with 10 combinations of vehicles (n = 4) and occupants (m = 8
Yang, ZhenhaoDesai, AmoghsiddBoyle, KyleRupp, JonathanReed, MatthewHu, Jingwen
Pyrotechnic seat belt pretensioners typically remove 8–15 cm of belt slack and help couple an occupant to the seat. Our study investigated pretensioner deployment on forward-leaning, live volunteers. The forward-leaning position was chosen because research indicates that passengers frequently depart from a standard sitting position. Characteristics of the 3D kinematics of forward-leaning volunteers following pretensioner deployment determines if body size is correlated with subject response. Nine adult subjects (three female), ages 18–43 years old, across a wide range of body sizes (50–120 kg) were tested. The age was limited to young, active adults as pyrotechnic pretensioners can deliver a notable force to the trunk. Subjects assumed a forward-leaning position, with 26 cm between C7 and the headrest, in a laboratory setting that replicated the passenger seat of a vehicle. At an unexpected time, the pretensioner was deployed. 3D kinematics were measured through a nine-camera motion
Hellenbrand, CiboneyBrown, J. FletcherGoodworth, Adam
Items per page:
1 – 50 of 2658