Browse Topic: Seats and seating

Items (1,714)
Five sled tests were performed with a Hybrid III (H-III) 10-year-old child sized Anthropomorphic Test Device (ATD) positioned in the 2nd row left seat of a three row 2006 Sport Utility Vehicle (SUV). A HYGE Sled buck was positioned to represent/replicate a side impact collision to the passenger (right) side of the SUV, with a Principal Direction of Force (PDOF) of 60 degrees, resulting in a far side side-impact for the ATD. Of the 5 tests performed, three of the five tests were performed with a delta-V of 17 mph, and two of the tests at a delta-V of 24 mph. Of the 17 mph tests, one test was performed with a properly restrained ATD, and two tests performed with improper restraint positioning. Both of the 24 mph tests were performed with improper restraint positioning, effectively identical to the two 17 mph delta-V tests. The two improper restraint use tests (at both 17 and 24 mph delta-V) included two different improper restraint scenarios. The first scenario of improper restraint
Luepke, PeterHewett, NatalieBetts, KevinVan Arsdell, WilliamWeber, PaulStankewich, CharlesMiller, GregoryWatson, RichardSochor, Mark
This paper contains Part 2 of a two-part paper series proposing potential regulatory approaches for occupant safety in Automated / Autonomous Vehicles (AVs) with unique seating configurations (stagecoach and campfire seating). Part 2 focuses on interior safety sensing, associated messaging, and ride control approaches both prior to and during a ride. Assessments are also proposed after significant vehicle braking and crash events. The proposed conditions are to be assessed in a static vehicle environment with humans segmented by occupant size and an infant dummy. On the vehicle seat and on the vehicle floor occupant detection conditions are proposed along with restraint usage detection conditions for vehicle seat belt usage, Child Restraint Seat (CRS) usage, CRS seat belt usage, and Lower Anchors and Tethers for Children (LATCH) system usage. These conditions may be detected by sensors / computer algorithms and human monitoring and thus are technology agnostic. The topics of animal
Thomas, Scott
Some Automated / Autonomous Vehicles (AVs) have unique seating configurations (stagecoach and campfire seating) which present expanded occupant safety challenges. Significant portions of the National Highway Traffic Safety Administration (NHTSA) Federal Motor Vehicle Safety Standards (FMVSS) do not yet align with AVs containing unique seating. This paper series takes the NHTSA occupant safety standard approach for conventional forward-facing seat vehicles where many compliance evaluations are in the frequently occupied front row and expands it to stagecoach and campfire AVs where the rear seating row is anticipated to be frequently occupied. The approaches proposed are from a logic-based safety-focused analysis and in many cases previously published material. The goal of this paper series is to offer regulatory proposals that enable equivalent performance for these AVs to existing forward-facing seating vehicle occupant safety standards and meet Executive Order 13045 on child safety
Thomas, Scott
Passenger comfort is becoming the forefront of luxury private jets where noise needs to be kept to a minimum. One source of structure-borne noise is the vibration of the Passenger Service Unit (PSU) panel. These vibrations originate from the outer skin, excited by turbulent boundary layer, and are transmitted through the fuselage frame to the PSU panel. This panel resides overhead of passenger seating, it is composed of a corrugated honeycomb core sandwiched between thin face-sheets. This paper presents a systematic approach to improve the vibro-acoustic performance of a honeycomb core sandwich structure by employing core filler and facesheet patches. Topology Optimization (TO) is used to determine the optimal layouts of these design modifications. The vibro-acoustic performance of the PSU panel with facesheet patches and core filler is evaluated using a frequency response analysis in the commercial finite element solver OptiStruct. The effectiveness of vibration reduction will be
Russo, ConnorWhetstone, IsobelPatel, AnujWotten, ErikKim, Il Yong
Head restraint requirements and designs have evolved to minimize the delay in head support and reduce differential loading in the neck. As a result, head restraints have become bigger and more angled forward, sitting, closer to the occupant’s head. Head restraints separation from seatbacks are sometimes observed in the field. Are head restraint detachments resulting from occupant comfort issues prior to the crash, occupant loading during the crash or were they removed by emergency personnel for extrication? Understanding the retention strength of head restraints and the type of evidence left behind by a forced removal may help researchers resolve the question of how a head restraint may be found post-crash separated from the seat. Quasistatic pull tests were conducted to measure vertical retention capabilities, compare vertical adjustment and release mechanisms, and document deformation and damage. Eighteen different front seat head restraint designs were evaluated. The model years
Parenteau, ChantalBurnett, RogerDavidson, Russell
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
The non-linear nature of crash scenarios has led to many designs being developed through extensive trial and error based on the intuitions of the design engineer. As such, effectively utilizing topology optimization for crash applications offers opportunities to provide major improvements in cost, weight, and passenger safety. Topology optimization is known for creating stiff, lightweight structures, however its application to crash scenarios must be handled carefully. Compliance minimization, the most common optimization objective, can yield misleading designs that prioritize undesirable qualities when developing structures for crash applications. In this paper, the design process of a passenger seat assembly subject to sequentially applied enforced displacement, and crash deceleration loads is discussed. Due to the conflicting nature of compliance minimization and enforced displacement, the design was split into two types of regions; sacrificial, which are regions manually designed
Orr, MathewShi, YifanLee, JakeGray, SavannahPark, TaeilWotten, ErikLeFrancois, RichardHuang, YuhaoPatel, AnujKim, HansuBurns, NicholasJalayer, ShayanGrant, RobertKok, LeoHansen, EricKim, Il Yong
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
Despite advances in crash avoidance, occupant restraint systems remain crucial in protecting the motoring public. Following decades of improvement in occupant protection, including several supplemental restraint systems for front seat occupants, the safety of rear seat occupants has recently undergone scrutiny. Studies evaluating rear seat occupant injury risk via field crash data have reported reduced relative safety in rear seating positions and alluded to advanced rear seat restraints, such as pretensioners and load limiters, as potential solutions. While the pursuit of novel technologies has historically improved occupant outcomes, evaluation of new systems in both controlled laboratory environments and field crashes is necessary to understand potential consequences of widespread introduction. This study analyzed the prevalence of advanced seat belts (load limiters and pretensioners) in the rear seating positions in the U.S. fleet. Additionally, occupant injury risk was compared
Rapp van Roden, Elizabeth AnnMiller, BrucePearson, JosephWilliamson, JamesBrown, Thomas
This paper presents a methodology for the design of a lightweight seat module assembly (SMA) for an indoor robotic arm amusement ride. Typical SMA designs begin with a welded metal frame, and the exterior shell serves only as a non-structural cover, resulting in stress concentrations and excess weight. The proposed methodology introduces a bottom-up process that integrates topology optimization at the outset, enabling the outer shell to function as a primary load path and subsequently identifies the ideal configuration for internal secondary framing by utilizing manufacturing constraints. This approach is further enhanced by adopting fiber-reinforced polymers as the structural material, leveraging their high stiffness-to-weight ratio to replace conventional metallic designs. Multiple manufacturing-specific interpretations of the optimized design were explored to evaluate feasibility, including extrusion and tubing-based approaches. Finite element analysis of the final design under high
Pooler, ClaireHronowsky, BenjaminChai, KevinShi, YifanPark, TaeilLo, DavidKim, Il Yong
This paper proposes an intelligent, artificial intelligence (AI) enabled seat heating system for school buses that saves energy by only activating heating elements when a passenger is identified. A custom-trained YOLOv8 deep learning model identifies passengers in real time and opens/closes real-time control of the individual electric seat heaters via a Raspberry Pi 5. The detector achieves around 10 frames-per-second (FPS) of inference on the Raspberry Pi 5 and 80–90 FPS on a laptop with over 92% detection confidence across various illumination conditions. Energy modeling shows the anticipated demand for a 10-kW propane-based heater is approximately 75% lower by implementing a 2.52 kW electric seat-heating system. In a typical operation schedule of 540 hours a year, this results in 4,000–5,000 kWh of annual savings, $465–$579 of annual cost savings and mitigates 0.9–1.3 t CO₂ per bus, annually. When implemented at the fleet level, the energy and cost saving will be in proportion. This
Chikkala, Daney BhargavZadeh, MehrdadTan, Teik-KhoonPonnam, JitinBatte, Jai Rathan
This paper presents a methodology for designing and evaluating lightweight, crashworthy aircraft seats that meet 21g crash safety standards and injury criteria. Four seat classes—double economy, single economy, premium economy, and business—were developed using a modular design strategy focused on part commonality (family of parts) and manufacturability. A shared family of structural components was implemented across all seat types, with dimensional modifications applied only, when necessary, due to differences in seat width or height. In such cases, the same material systems and design principles were used to ensure consistency and reduce manufacturing complexity. The designs were evaluated using finite element simulations to verify performance under aerospace crash conditions. Each seat configuration was validated against regulatory crashworthiness criteria and injury thresholds, including pelvic, lumbar, and femur compressive forces, as well as head injury criteria (HIC) values. The
Gray, SavannahOrr, MathewShi, YifanPark, TaeilLee, JakeWotten, ErikLeFrancois, RichardHuang, YuhaoPatel, AnujKim, HansuBurns, NicholasJalayer, ShayanGrant, RobertKok, LeoHansen, EricKim, Il Yong
Rear-facing infant seats that are positioned behind front outboard vehicle seats are at risk of being compromised by the rearward yielding of occupied front seat seatbacks during rear-impact collisions. This movement can cause the plastic shell of the infant seat to collapse and deform, increasing the risk of head injuries to the infant. Current designs of rear-facing infant seats typically do not consider the loading effects from the front seatback during rear-impact situations, which results in weak and collapsible shell structures. Moreover, regulatory compliance tests, such as FMVSS 213, do not include assessments of rear-facing infant seats under realistic rear-impact conditions. as the bench used for the regulatory test lacks realistic vehicle interior components. This study emphasizes the need for revised testing methodologies that employ sled tests with realistic seatback intrusion conditions to facilitate the development of improved infant seat designs. Research shows that
Thorbole, Chandrashekhar
The automotive industry constantly strives to enhance vehicle safety, comfort, and customer satisfaction. One of the critical aspects influencing these factors is the mitigation of Buzz, Squeak, and Rattle (BSR) issues, which can significantly impact perceived vehicle quality and user experience. This paper focuses on the BSR challenges specifically encountered in bench seat latch & striker mechanisms. Vibrations and movement, especially during vehicle operation, exacerbate Buzz, Squeak & Rattle (BSR) problems, leading to acoustic disturbances that detract from the overall ride quality. Latch and striker in seat system is prone to squeaks and rattles (S&R) due to improper fitment, environmental conditions, or mechanical stress. These issues not only compromise the auditory experience but may also raise concerns about component durability and functionality. This paper outlines the root causes of BSR phenomena in these components, emphasizing the role of design optimization, material
Deole, Sameer ShrikantRahman, ShafeeqMohammed, RiyazuddinShah, Prashant
Seats of modern cars should necessarily meet the regulatory safety norms along with aesthetics and comfort. In the existing passenger cars prevailing across the Indian subcontinent, the measure of safety has been a challenging one. The stringent regulatory norms thereby make the Airbag very promising. In the Automotive industry, safety features are very important, one of the topmost features which falls in this category is airbags. The driver and passenger safety during high impact collisions and sudden crashes is the key objective of airbag. This safety is provided by the airbag with its automatic deployment. The inflatable airbag is engineering in a way to respond very quickly during a collision and furnish necessary cushioning to decrease the impulse and enhance the safety of the passenger. The technology has been practiced widely upon many vehicles' seats. However, the present work highlights a novel approach of packaging the HPTS air bag in second row seat. This Air bag unit is
Buradkar, RajatBose, KarthikJadhav, DeepikaBalakrishnan, Gangadharan
This research paper investigates the failure of an isolator clip used in the seat slider assembly, which guides and restricts the sliding motion of the tooth bracket within the seat. The component is made of C80 high-carbon spring steel, known for its high strength. According to the manufacturing process details, zinc plating was applied to the component for corrosion protection, as confirmed by EDS analysis. A fractographic examination of the failed part revealed a brittle, intergranular fracture morphology with visible cracks. Certain areas also exhibited micro-void coalescence, indicating a dimpled fracture surface. The primary failure mode was intergranular (IG) fracture. The delayed fracture was attributed to intergranular fracture mechanisms, micro-void coalescence, and the high strength of the steel, which made the component susceptible to hydrogen embrittlement. Hydrogen embrittlement occurs when hydrogen atoms become trapped along the grain boundaries, where they form hydrogen
Saindane, Mehul KishorBali, Shirish
In this study, an intelligent monitoring system for electric vehicle seats based on flexible pressure sensor array is proposed. Through the design of multi-layer composite film structure and the collaborative development of STM32 embedded platform, high-precision sensing (error<5%) and rapid response (<200ms) of pressure distribution are realized. The experimental results show that the linearity of the sensor array is ± 1.5% FS in the range of 0-100kpa, and the dynamic response time is 3.6 times higher than that of the traditional sensor; By establishing a three-level adjustment algorithm (fuzzy PID+LSTM prediction+genetic optimization), the seat comfort is improved by 20.5%, and the system energy consumption is reduced by 33.5%. The research provides theoretical and technical support for the transformation of intelligent seats from “passive support” to “active interaction”.
Huang, YifengRong, DaozhiLin, GuoyongHuang, ZhenguiWang, RuliangTao, Chengxi
In order to meet the high lightweight and transmission accuracy requirements of a certain airborne system, the seat ring bearing adopts a lightweight material 4-point contact ball slewing bearing. However, the non-linear contact of a large number of balls during the working process of the seat ring makes simulation difficult, and ball damage often occurs in previous experiments. Based on the bearing capacity of the shaft, the influence of uneven load transmission of the ball on the response was considered. The response of the bearing under shooting and airdrop landing impact loads was calculated and analyzed using multi rigid body and finite element methods, respectively. The results indicate that under the impact load, the stress on the ball has exceeded the yield limit of the material, resulting in irreversible plastic deformation. The plastic deformation morphology is basically consistent with the damage morphology of the test ball, which verifies the accuracy of the simulation
Zhang, TaipingNing, BianfangWang, HuatingFan, He
Belt-positioning booster seats (BPBs) help promote proper seat belt fit for children in vehicles. The effectiveness of BPBs depends on occupant posture, which can be influenced by BPB design features. This study aimed to quantitatively describe how children's postures naturally change over time in BPBs, using pressure mats. Thirty children aged 5 to 12 participated in two 30-minute trials using randomly assigned seating configurations. Five configurations were studied by installing two backless BPBs in vehicle captain’s chairs, varying booster profile (high, low, or no BPB) and armrest presence (with or without BPB/vehicle seat armrests). TekScan 5250 pressure mats were placed on the seating surfaces. Children began in an ideal reference posture, and center of force (COF) data were collected continuously. Additional observations on posture, behavior, and comfort were periodically collected. Mixed models, including effects of seating configuration, time, and volunteer characteristics
Connell, RosalieBaker, Gretchen H.Mansfield, Julie A.
Combining simulation with probabilistic ML enables engineers to chart the full design landscape, quantify uncertainty and uncover viable options that intuition and brute force alone would miss. Components and systems are routinely designed and validated virtually through tools like CFD and FEA before any physical prototype is built. The benefits are obvious: faster iteration, reduced cost and better products. But simulation is not cheap. Each run can take hours, consume costly GPU/CPU resources and require highly skilled engineers who are already in short supply. Licenses and compute costs can easily reach tens of thousands of dollars per seat, and most teams can complete only a few runs per day.
Appleyard, Nick
To enhance the predictive accuracy between seat structural parameters and crash performance, a hybrid model was constructed by coupling an Improved Particle Swarm Optimization (IPSO) algorithm with a Back Propagation Neural Network (BPNN). First, a finite element model for front and rear impact of automotive seats was established based on experimental data, and the model’s accuracy was verified. Subsequently, simulations were conducted, and the results were analyzed. The Energy Absorption Mass Ratio method was used to screen the design variables, ultimately selecting 10 thickness variables and 9 material variables as design variables. Latin Hypercube Sampling was employed to divide the dataset into a testing set and a training set. Then, the Particle Swarm Optimization (PSO) was enhanced with Levy flights and a local mutation strategy, utilizing the IPSO algorithm to optimize the initial weights and thresholds of the BPNN, resulting in the establishment of the IPSO-BPNN predictive
Qiu, YufeiLong, Jiangqi
This SAE Aerospace Standard (AS) defines minimum performance standards, qualification requirements, and minimum documentation requirements for passenger and crew seats in civil rotorcraft, transport aircraft, and general aviation aircraft. The goal is to achieve comfort, durability, and occupant protection under normal operational loads and to define test and evaluation criteria to demonstrate occupant protection when a seat/occupant/restraint system is subjected to statically applied ultimate loads and to dynamic impact test conditions set forth in Title 14, Code of Federal Regulations (14 CFR) parts 23, 25, 27, or 29 (as applicable to the seat type). Two formats of this standard (MS Excel and Adobe PDF) are available. The standards provided in both formats (MS Excel and Adobe PDF) contain the same text.
Aircraft Seat Committee
This study aims to develop a lightweight bus passenger seat frame by conducting structural nonlinear finite element analysis (FEA) on various thickness combinations of seat frame components to identify the optimal configuration. The thicknesses of critical structural members that primarily bear the load when force is applied to the seat frame were selected as independent variables, while stress on each component and compliance with ECE R14 seatbelt anchorage displacement regulations were set as dependent variables. A regression analysis was performed to calculate the importance of each component and analyze the influence of each design variable on the dependent variables. Strain gauges were attached to critical areas of the actual seat frame to conduct a seatbelt anchorage test, and simulations under identical conditions were performed using the nonlinear FEA software (LS-DYNA) to validate the reliability of the analysis results. The optimized seat frame exhibited a maximum stress of
Ko, Yeong GookCho, Kyu ChunLee, Ji SunKang, Ki Weon
Subjective perception of vehicle secondary ride is dependent on simultaneous touchpoint vibrations and audible inputs to the occupants. Standards such as ISO 2361 provide guidelines for objective assessments of human body thresholds to vibration [1]. However, when a human experiences vibration inputs at multiple touchpoints, as well as aural inputs, it becomes complicated to judge each individual contribution to the overall subjective perception [2]. Additional factors, such as ambient conditions, ergonomics, age, gender etc. also play a role. Secondary ride, which is defined as energy in the 10-30 Hz frequency range, is one such event that affects the customers’ perception of ride comfort and quality. The goal of this work is to develop a sound and vibration simulator model and execute a secondary ride jury study of vehicle driving over cleats. The aim of the study is to rank the contributions of each touch point vibration input, as well as sound to the overall subjective perception
Jayakumar, VigneshJoodi, BenjaminGeissler, ChristianPilz, FernandoLynch, LukeConklin, ChrisWeilnau, KelbyHodgkins, Jeffrey
Analyzing acoustic performance in large and complex assemblies, such as vehicle cabins, can be a time-intensive process, especially when considering the impact of seat location variations on noise levels. This paper explores the use of Ansys simulation and AI tools to streamline this process by predicting the effects of different speaker locations and seat configurations on cabin noise, particularly at the driver’s ear level. The study begins by establishing a baseline simulation of cabin noise and generating training data for various seat location scenarios. This data is then used to train an AI model capable of predicting the noise impact of different design adjustments. These predictions are validated through detailed simulations. The paper discusses the accuracy of these predictions, the challenges encountered and provides insights into the effective use of AI models in acoustic analysis for cabin noise, with a specific emphasis on seat location as a key variable.
Kottalgi, SantoshHe, JunyanBanerjee, Bhaskar
In single-aisle aircraft, the available storage space for carry-on baggage is inherently limited. When the aircraft is fully booked, it often results in insufficient overhead bin space, necessitating last-minute gate-checking of carry-on items. Such disruptions contribute to delays in the boarding process and reduce operational efficiency. A promising approach to mitigate this issue involves the integration of computer vision technologies with an appropriate data storage system and stochastic simulation to enable accurate and supportive predictions that enhance planning, reduce uncertainty, and improve the overall boarding process. In this work, the YOLOv8 image recognition algorithm is used to identify and classify each passenger’s carry-on baggage into predefined categories, such as handbags, backpacks, and suitcases. This classified data is then linked to passenger information stored in a NoSQL database MongoDB, which includes seat assignments and the number of carry-on items
Bergmann, JacquelineHub, Maximilian
Increasing digitalization of the aircraft cabin, driven by the need for improved operational efficiency and an enhanced passenger experience, has led to the development of data-driven services. In order to implement these services, information from different systems is often required, which leads to a multi-system architecture. When designing a network that interconnects these systems, it is important to consider the heterogeneous device and supplier landscape as well as variations in the network architecture resulting from airline customization or cabin upgrades. The novel ARINC 853 Cabin Secure Media-Independent Messaging (CSMIM) standard addresses this challenge by specifying a communication protocol that relies on a data model to encode provided and consumed information. This paper presents an approach to integrate CSMIM-specific communication concepts into a Model-Based Systems Engineering (MBSE) framework using the Systems Modeling Language (SysML). This enables a streamlined
Giertzsch, FabianBlecken, MarvinGod, Ralf
This SAE Aerospace Standard (AS) defines minimum performance standards and related qualification criteria for add-on child restraint systems (CRS) which provide protection for small children in passenger seats of transport category airplanes. The AS is not intended to provide design criteria that could be met only by an aircraft-specific CRS. The goal of this standard is to achieve child-occupant protection by specifying a dynamic test method and evaluation criteria for the performance of CRS under emergency landing conditions.
Aircraft Seat Committee
This document is a guide to the application of magnesium alloys to aircraft interior components including but not limited to aircraft seats. It provides background information on magnesium, its alloys and readily available forms such as extrusions and plate. It also contains guidelines for “enabling technologies” for the application of magnesium to engineering solutions including: machining, joining, forming, cutting, surface treatment, flammability issues, and designing from aluminum to magnesium.
Aircraft Seat Committee
This Aerospace Recommended Practice (ARP) defines acceptable methods for determining the seat reference point (SRP), and the documentation requirements for that determination, for passenger and crew seats in Transport Aircraft, Civil Rotorcraft, and General Aviation Aircraft.
Aircraft Seat Committee
Ride comfort is an important factor in the development of vehicles. Understanding the characteristics of seat components allows more accurate analysis of ride comfort. This study focuses on urethane foam, which is commonly used in vehicle seats. Soft materials such as urethane foam have both elastic and viscous properties that vary with frequency and temperature. Dynamic viscoelastic measurements are effective for investigating the vibrational characteristics of such materials. Although there have been many studies on the viscoelastic properties of urethane foam, no prior research has focused on dynamic viscoelastic measurements during compression to simulate the condition of a person sitting on a seat. In this study, dynamic viscoelastic measurements were performed on compressed urethane foam. Moreover, measurements were conducted at low temperatures, and a master curve using the Williams–Landel–Ferry (WLF) formula (temperature–frequency conversion law) was created.
Kamio, ChihiroYamaguchi, TakaoMaruyama, ShinichiHanawa, KazutoIwase, TsutomuHayashi, TatsuoSato, ToshiharuMogawa, Hajime
This practice presents methods for establishing the driver workspace. Methods are presented for: Establishing accelerator reference points, including the equation for calculating the shoe plane angle Locating the SgRP as a function of seat height (H30) Establishing seat track dimensions using the seating accommodation model Establishing a steering wheel position Application of this document is limited to Class-A Vehicles (Passenger Cars, Multipurpose Passenger Vehicles, and Light Trucks) as defined in SAE J1100.
Human Accom and Design Devices Stds Comm
At present, electric head restraints have been developed locally, so overseas mechanisms are used. In this study, two concept mechanisms were developed, and in addition, one patent for a wing-out head restraint mechanism was additionally applied. The new mechanism has had an excellent effect on cost reduction and improvement of operating noise compared to the current one.
Yu, Sanguk
The National Highway Traffic Safety Administration (NHTSA) published an Advance Notice of Proposed Rulemaking (ANPRM) to update the Federal Motor Vehicle Safety Standard (FMVSS) 207. Part of the ANPRM is to assess the merit of conducting quasi static body block seat pull tests and conducting FMVSS 301 rear crash tests at 80 km/h or higher with a 95th percentile ATD lap-shoulder belted in the front seats and limiting seatback deflection to 15 to 25 degrees. Prior to updating regulations, it is important to understand the seating design history and implications. This study was conducted to provide a historical background on seat design and performance using literature and test data. One objective was to first define the terminology used to describe occupant kinematics in rear crashes. Secondly, seat design evolution is then discussed. Third, test methods and test results were summarized, and fourth, the field performance are synopsized and discussed with respect to 2nd row occupant
Parenteau, ChantalBurnett, RogerDavidson, Russell
The National Highway Safety Administration (NHTSA) recently published an Advanced Notice of Proposed Rulemaking (ANPRM) to evaluate seat performance in rear impacts [1]. The ANPRM was issued partially in response to two petitions requesting an increase in seatback strength requirements and high-speed testing with various size Anthropometric Test Devices (ATDs). To better understand the effect of these requests, this study evaluates ATD responses with two high-speed rear sled conditions, three occupant sizes and various seat designs. Seat designs varied from modern conventional seats with yielding properties to stronger and stiffer seats represented by seat integrated restraint (SIR) designs, and rigidized SIR seats. Twenty-four rear sled tests were analyzed. The tests were matched by crash severity, seat designs (strength), ATD sizes and initial postures (nominal/in-position, leaned forward and leaned outboard). The test data and videos were reviewed to identify time coinciding with
Parenteau, ChantalBurnett, Roger
Automotive seating systems have become increasingly sophisticated, providing consumers with more flexible configurations and comfort functionalities. Traditional power seating, which relied on a few motors to adjust the seat position, has evolved into more technically advanced reconfigurable systems equipped with additional feedback sensors and actuators. These advancements include features such as Easy Entry, Zero Gravity, Stadium Swivel, IP Nesting, Auto Lumbar/Bolster Adjustment and Power Long Rails. All the features indicate that the overall control of seating systems now resembles robotic arm control or multi-body control, involving numerous coordinated movements. In this paper, we propose a novel control strategy for the coordinated speed control of multiple motors. Unlike traditional seating controls, which typically use direct switches or open-loop systems, we introduce a feedback approach that incorporates Kalman-filter-based speed estimation using raw signals directly from
Yang, HanlongLi, Miranda
A reconfigurable experimental seat is useful for seating comfort research and allows researchers to investigate the effects of seat parameters and to propose quantitative guidelines for improving seat comfort. Since 2017, Gustave Eiffel University has such an experimental seat which allows us to carry out parametric studies on the geometric dimensions of a seat and to understand the role of the contact force, particularly that in shear force. Equipped with force and positioning sensors, all contact forces and seat position can be measured. More specifically, it is equipped on the seat with a matrix of 52 cylinders, each adjustable in height and each equipped with a three-axis force sensor. These cylinders make it possible to vary the contact surface of seat pan and measure the distribution of contact forces. More recently, a new system with a matrix of 263 hydraulic cylinders was designed and manufactured to better study the comfort of the backrest in replacement of the three-support
Wang, XuguangBeurier, Georges
The effectiveness of the negative suspension structure (NSS) in isolating the driver’s seat vibrations has been demonstrated based on the seat’s model or vehicle’s one-dimensional dynamic model. To fully assess the effectiveness and stability of the seat’s NSS (S-NSS) on different models of vehicles, the three-dimensional models of the vibratory rollers (VR), heavy trucks (HT), and passenger cars (PC) have been built to assess the effectiveness of S-NSS compared to the seat’s passive suspension (S-PC) and seat’s control suspension (S-CS). The effectiveness of S-NSS is then investigated under all operating conditions of vehicles. The investigation results indicate that under a same simulation condition, S-NSS improves the ride comfort and health of the driver better than both S-PS and S-CS on all VR, HT, and PC. However, the effectiveness of S-NSS on PC is lower than on both VR and HT while the effectiveness of S-CS on PC is better than on both VR and HT. Besides, the effectiveness of S
Su, BeibeiWang, QiangSong, Fengxiang
The comfort of seats increasingly becomes a crucial factor in the overall driving experience, particularly as vehicles become increasingly integrated into people’s daily lives. Passengers often maintain a relatively fixed posture and have close contact with the seat for extended periods of time, leading to issues such as heat, humidity, and stickiness. In order to enhance the thermal comfort experienced by occupants, manufacturers are no longer satisfied with ensuring the thermal comfort performance of vehicles only through the HVAC system in the cabin, but also developed a microclimate control seat that adjusts the temperature through ventilation between the contact surface of the seat and the human body, trying to improve the thermal comfort of passengers more effectively. However, the ventilation ducts of these seats are commonly designed based on empirical or autonomous standards, and their effectiveness is subsequently assessed through test or simulation, typically under unloaded
Zhang, TianmingRen, JindongZhang, Haonan
Vehicles equipped with automated driving systems (ADS) may have non-traditional seating configurations, such as rear-facing for front-row occupants. The objectives of this study are (1) to generate biomechanical corridors from kinematic data obtained from postmortem human subjects (PMHS) sled tests and (2) to assess the biofidelity of the Global Human Body Models Consortium (GHBMC) 50th male (M50-O) v6.0 seated in an upright (25-deg recline) Honda Accord seat with a fixed D-ring (FDR) in a 56 km/h rear-facing frontal impact. A phase optimization technique was applied to mass-normalized PMHS data for generating corridors. After replicating the experimental boundary conditions in the computational finite element (FE) environment, the performance of the rigidized FE seat model obtained was validated using LSTC Hybrid III FE model simulations and comparison with experiments. The most recent National Highway Traffic Safety Administration (NHTSA) Biofidelity Ranking System (BRS) method was
Pradhan, VikramRamachandra, RakshitStammen, JasonKracht, CoreyMoorhouse, KevinBolte, John H.Kang, Yun-Seok
With the advancement of lightweight magnesium-based hybrid composites, are potential for weight management applications. The liquid state stir cast process is the best way to produce complex shapes and most industries are preferred. However, the melting of magnesium alloy and achieving homogenous particle distribution are the major challenges for the conventional stir-casting process, and hot crack formation is spotted due to thermal variations. The main objectives of the present research are to enhance the microstructural and mechanical behaviour of magnesium alloy hybrid nanocomposite (AZ91E) adopted with boron carbide (B4C) and alumina (Al2O3) nanoparticles through a semisolid stir cast technique associated with inert atmosphere helps to limits the oxide formation and reduce risk of magnesium fire. The effect of composite processing and multiple reinforcements on surface morphology, tensile strength, impact strength, and hardness were thoroughly evaluated and compared. The results
Manivannan, S.Venkatesh, R.Kaliyaperumal, GopalKarthikeyan, S.Mohanavel, VinayagamSoudagar, Manzoore Elahi MohammadKarthikeyan, N.
This Recommended Practice provides a procedure to locate driver seat tracks, establish seat track length, and define the SgRP in Class B vehicles (heavy trucks and buses). Three sets of equations that describe where drivers position horizontally adjustable seats are available for use in Class B vehicles depending on the percentages of males to females in the expected driver population (50:50, 75:25, and 90:10 to 95:5). The equations can also be used as a checking tool to estimate the level of accommodation provided by a given length of horizontally adjustable seat track. These procedures are applicable for both the SAE J826 HPM and the SAE J4002 HPM-II.
Truck and Bus Human Factors Committee
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.
Three dynamic models of a passenger car including the one-dimensional dynamic model, two-dimensional dynamic model, and three-dimensional dynamic model are built to evaluate the ride quality of the passenger car as well as the isolating performance of the SNS (structure of negative stiffness). The decrease of the root-mean-square (RMS) accelerations in the seat and car’s body shaking is the research goal. The investigation results indicate that under all working conditions including the various excitations of the road surface and various velocities of the passenger car, the seat’s acceleration with SNS is strongly ameliorated in comparison without SNS in all three models of the passenger car. Particularly, the RMS seat acceleration with SNS in one-, two-, and three-dimensional models is strongly reduced in comparison without SNS by 76.87%, 66.15%, and 70.59%, respectively. Thus, the seat’s SNS has a good effect in isolating the vertical vibration of the passenger car’s seat. However
Zhang, LeiLi, TaoYang, Guixing
This SAE Standard provides a test method, an evaluation method, and a performance criterion for shock-absorbing characteristics of a general foam-type snowmobile seat. This SAE Standard applies to seats that are similar in design, dimensions, construction, and/or intended usage as described and illustrated in SAE J33.
Snowmobile Technical Committee
Some challenges, such as reworking airbags to meet all seating scenarios, will be solved by the OEM as the final system integrator. Rearward-facing front seats have generally been limited to concept cars that explore a far-away world in which SAE Level 5 autonomous driving has been perfected. Magna has rewritten that playbook, winning a contract with a Chinese OEM for a reconfigurable seating system that includes fully rotating front seats on long rails, creating an unusually flexible cabin. Currently configured for vehicles with two rows of seating, the system features power-swivel seats along rails or tracks nearly two meters (6.6 ft) long. The front passenger and driver seats can rotate 270 degrees.
Clonts, Chris
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