Search Results

Recent field data have shown that the occupant protection in vehicle rear seats failed to keep pace with advances in the front seats likely due to the lack of advanced safety technologies. The objective of this study was to optimize advanced restraint systems for protecting rear seat occupants with a range of body sizes under different frontal crash pulses. Three series of sled tests (baseline tests, advanced restraint trial tests, and final tests), MADYMO model validations against a subset of the sled tests, and design optimizations using the validated models were conducted to investigate rear seat occupant protection with 4 Anthropomorphic Test Devices (ATDs) and 2 crash pulses.

Define recommendations for color coding of child restraint labels, specifically focused on the information contained therein and whether it provides information for installation in a forward facing, rear facing, or booster mode.

Dynamic impact test represent various automotive collision conditions. The impact testing recommended practice is intended to recognize the capabilities of autonomous vehicles while at the same time recognizing the vehicle fleet into which they are introduced will consist of non-autonomous vehicles for a considerable period of time. The scope of the document is to cover the range of impact conditions expected taking into account the capabilities of the vehicle and the impact testing technology now available for performance evaluation including virtual and physical testing.

1. SCOPE These guidelines should be considered: When implementing the LATCH system in vehicle seating positions that will be designated by the vehicle owner’s manual and in the information included in the owners manual. When implementing the LATCH system in child restraint designs that include the LATCH system and in the information included in the instruction manual

This document provides recommended practices for impact testing of ground vehicle that are also aero-capable. The scope characterizes recommended impact testing taking into account the unique design characteristics involved in aero-capable ground vehicle

Accident data show that the head and the chest are the most frequently injured body regions in side impact fatal accidents. Curtain side air bag (CSA) and thorax side air bag (SAB) have been installed by manufacturers for the protection devices for these injuries. In this research, first we studied the recent side impact accident data in Japan and verified that the head and chest continued to be the most frequently injured body regions in fatal accidents. Second, we studied the occupant seating postures in vehicles on the roads, and found from the vehicle's side view that the head location of 56% of the drivers was in line or overlapped with the vehicle's B-pillar. This observation suggests that in side collisions head injuries may occur frequently due to contacts with the B-pillar. Third, we conducted a side impact test series for struck vehicles with and without CSA and SAB.

The development of a repeatable dynamic rollover test methodology with meaningful occupant protection performance objectives has been a longstanding and unmet challenge. Numerous studies have identified the random and chaotic nature of rollover crashes, and the difficulty associated with simulating these events in a laboratory setting. Previous work addressed vehicle level testing attempting to simulate an entire rollover event but it was determined that this test methodology could not be used for development of occupant protection restraint performance objectives due to the unpredictable behavior of the vehicle during the entire rollover event. More recent efforts have focused on subsystem tests that simulate distinct phases of a rollover event, up to and including the first roof-to-ground impact.

As software (SW) becomes more and more an important aspect of embedded system development, project schedules are requiring the earlier development of software simultaneously with hardware (HW). In addition, verification has increasingly challenged the design of complex mixed-signal SoC products. This is exacerbated for automotive safety critical SoC products with a high number of analogue interfaces (sensors and actuators) to the physical components such as an airbag SoC chipset. Generally, it is widely accepted that verification accounts for around 70% of the total SoC development. Since integration of HW and SW is the most crucial step in embedded system development, the sooner it is done, the sooner verification can begin. As such, any approaches which could allow verification and integration of HW/SW to be deployed earlier in the development process and help to decrease verification effort, (e.g.: accelerate verification runs) are of extreme interest.

As one of the most important auto-body moving parts, door hinge is the key point of door design and its accessories arrangement, also the premise of the door kinematic analysis. We proposed an effective layout procedure for door hinge and developed an intelligent system on CATIA CAA platform to execute it. One toolbar and five function modules are constructed - Axis Arrangement, Section, Parting Line, Kinematic, Hinge Database. This system integrated geometrical algorithms, automatically calculate the minimum clearances between doors, fender and hinges on sections to judge if the layout is feasible. As the sizes of the clearances are set to 0s, the feasible layout regions and extreme start/end points are shown in parts window, which help the engineer to check the parting line and design a new one. Our system successfully implemented the functions of five modules for the layout of door hinge axis and parting line based on a door hinge database.

Obesity rates are increasing among the general population. This study investigates the effect of obesity on ejection and injury risk in rollover crashes through analysis of field accident data contained in the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) database. The study involved front outboard occupants of age 15+ years in 1994+ model year vehicle rollover crashes. Occupants were sorted into two BMI groups, normal (18.5 kg/m2 ≤ BMI < 25.0 kg/m2) and obese (BMI ≥30 kg/m2). Complete and partial ejection risks were first assessed by seating location relative to roll direction and belt use. The risk of serious-to-fatal injuries (MAIS 3+F) in non-ejected occupants were then evaluated. The overall risk for complete ejection was 2.10% ± 0.43% when near-sided and 2.65% ± 0.63% when far-sided, with a similar risk for both the normal and obese BMI groups.

This paper focuses on the analysis and evaluation of acoustical design criteria to produce a plausible 3D sound field solely via headrest with integrated loudspeakers at the driver/passenger seats in the car cabin. Existing audio systems in cars utilize several distributed loudspeakers to support passengers with sound. Such configurations suffer from individual 3D audio information at each position. Therefore, we present a convincing minimal setup focusing sound solely at the passenger’s ears. The design itself plays a critical role for the optimal reproduction and control of a sound field for a specific 3D audio application. Moreover, the design facilitates the 3D audio reproduction of common channel-based, scene-based, and object-based audio formats. In addition, 3D audio reproduction enables to represent warnings regarding monitoring of the vehicle status (e.g.: seat belts, direction indicator, open doors, luggage compartment) in spatial accordance.

With the continuous improvement of vehicle air leakage performance, an aural discomfort phenomenon had been occurred at the instant of vehicle door closing. There are many studies on door closing sound quality in past 20 years, but there is little publications on the study of the aural discomfort due to a transient high air pressure fluctuations. In this paper, the relationships of passenger’s aural discomfort produced by interior air pressure fluctuations are systematically studied. The ratio of door surface area to passenger compartment volume and other related parameters such as the cross-sectional area of a vehicle, the air extractor size, and the vehicle body air leakage under positive pressure are also studied through CAE analysis and verified through a large number of objective measurements and subjective vehicle evaluation.

The experimental campaign discussed in publication 2019-01-0635 was extended to emulate more vehicle parameters and also to increase severity leading to deployment event. The engine speed (RPM) and Accelerator Pedal Position (APP) were emulated using LabVIEW and added to the previously reported emulated parameters of wheel speeds and brake status. Overlapping non-deployment events were generated and the EDR data is presented enriched with additional (faster) CAN bus data sniffed from the vehicle harness. While the non-deployment events were still generated using the rubber mallet in pendulum configuration as in 2019-01-0635, a series of tests were performed using an Izod pendulum to incrementally increase event severity until deployment event was generated. The Izod pendulum was instrumented with a rotational potentiometer to measure its instantaneous angle while laboratory accelerometers were used to separately measure acceleration.

This paper describes a multi-degree-of-freedom model of a three-wheeled car implemented in Matlab®. The purpose was to investigate the dynamics of the car (assumed to be rigid on its suspension) during cornering. While the problems associated with three-wheeled cars are well known, much of the guidance in the literature and off-the-shelf software assumes a conventional four-wheeled car. Consequently, the authors were approached with a battery-electric concept car which was thought to offer better performance than the existing variants because the use of hub motors lowered the center of gravity and, hence, reduced rollover coefficient. However, simulation of the vehicle model in cornering shows that the concept is still prone to instability. Indeed, it suffers greater roll velocities than a comparable three-wheeled car with an internal combustion engine (ICE) because the ratio of sprung to unsprung mass is significantly altered.

Squeak and rattle concerns accounts for approximately 10% of overall vehicle Things Gone Wrong (TGW) and are major quality concern for automotive OEM’s. Objectionable door noises such as squeak and rattle are among the top 10 IQS concerns under any OEM nameplate. Customers perceive Squeak and rattle noises inside a cabin as a major negative indicator of vehicle build quality and durability. Door squeak and rattle issues not only affects customer satisfaction index, but also increase warranty cost to OEM significantly. Especially, issues related to door, irritate customers due to material incompatibilities. Squeaks are friction-induced noises generated by stick-slip phenomenon between interfacing surfaces. Several factors, such as material property, friction coefficient, relative velocity, temperature, and humidity, are involved in squeak noise causes.

Rollover has for long been a major safety concern for trucks, and will be even more so as automated driving is envisaged to becoming a key element of future mobility. A natural way to address rollover is to extend the capabilities of current active-safety systems with a system that intervenes by steering or braking actuation when there is a risk of rollover. Assessing and predicting the rollover is usually performed using rollover indices calculated either from lateral acceleration or lateral load transfer. Since these indices are evaluated based on different physical observations it is not obvious how they can be compared or how well they reflect rollover events in different situations. In this paper we investigate the implication of the above mentioned rollover indices in different critical maneuvers for a heavy 8×4 twin-steer truck.

The intent of this paper is to document comprehensive test-based approach to analyze the door-closing event and associated sound using structural and acoustic loads developed during the event. This study looks into the door-closing phenomenon from the structural interaction point of view between the door and the body of the vehicle. The study primarily focuses on distributing the door and body interaction as discrete multiple structural and acoustic phenomena. It also emphasizes on the structural and acoustic loads developed by the discretized interactions at the interfaces between the door and the body frame. These interfaces were treated to be the load paths from the door to the body. The equivalent structural and acoustic loads were calculated indirectly using the well-known Transfer Path Analysis (TPA) methodology for structural loads and the Acoustic Source Quantification (ASQ) methodology for acoustic loads.

Transfer or response equations are important as they provide relationships between the responses of different surrogates under matched, or nearly identical loading conditions. In the present study, transfer equations for different body regions were developed via mathematical modeling. Specifically, validated finite element models of the age-dependent Ford human body models (FHBM) and the mid-sized male Hybrid III (HIII50) were used to generate a set of matched cases (i.e., 192 frontal sled impact cases involving different restraints, impact speeds, severities, and FHBM age). For each impact, two restraint systems were evaluated: a standard three-point belt with and without a single-stage inflator airbag. Regression analyses were subsequently performed on the resulting FHBM- and HIII50-based responses. This approach was used to develop transfer equations for seven body regions: the head, neck, chest, pelvis, femur, tibia, and foot.

Studies have shown that the number of road accidents caused by rollover both in Europe and in Turkey is increasing [1]. Therefore, rollover related accidents became the new target of the studies in the field of vehicle dynamics research aiming for both active and passive safety systems. This paper presents a method for optimizing the rear suspension geometry using design of experiment and multibody simulation in order to reduce the risk of rollover. One of the major differences of this study from previous work is that it includes statistical Taguchi method in order to increase the safety margin. Other difference of this study from literature is that it includes all design tools such as model validation, optimization and full vehicle handling and ride comfort tests. Rollover angle of the vehicle was selected as the cost function in the optimization algorithm that also contains roll stiffness and height of the roll center.

In order to provide an accurate estimation of fatigue life of automotive door hinges and check strap mounting location, it is crucial to understand the loading conditions associated with opening and closing the door. There are many random factors and uncertainties that affect the durability performance of hinge and check strap mount structures in either a direct or indirect way. Excessive loads are generated at the hinge and check arm mounting region during abuse conditions when opening the door. Repeating the abuse conditions will lead to fatigue failures in these components. Most influencing parameter affecting the fatigue performance for the door was the loads due to hinge-check arm sensitivity stoppage and the distance between hinge and check strap attachments. However, the probability of occurrences was low, but the impact is high.