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Up to now, the reliability achieved by COTS components was largely sufficient for avionics, in terms of failure rate as well as time to failure. With the implementation of new and more integrated technologies (90 nm node, 65 nm and below), the question has arisen of the impact of the new technologies on reliability. It has been stated that the lifetime of these new technologies might decrease. The drift is expected to be technology dependent: integration, technology node, materials, elementary structure choices and process pay a key role. Figures have been published, which gives smaller lifetime than the 30 years generally required for avionics. This would of course impact not only the reliability, but also the maintenance of COTS-based avionics. Hence a new policy should be defined for the whole COTS supply chain. Faced with these impending risks, different methodologies have been developed.

Alyson Lyon, Executive Leadership Coach, explains what stress is, and how to handle personally and professionally. SAE Members can view the full version by logging into the Member Connection. Not a Member? Join us today at sae.org/join.

“Spotlight on Design: Insight” features an in-depth look at the latest technology breakthroughs impacting mobility. Viewers are virtually taken to labs and research centers to learn how design engineers are enhancing product performance/reliability, reducing cost, improving quality, safety or environmental impact, and achieving regulatory compliance. Extreme environment sensors require extreme environment cables that can reliably perform in temperatures up to 2300° F, withstand intense vibration, and have extraordinary strength. In the episode “Sensors: Noise Avoidance and Cable Manufacturing” (8:53), an engineer at Meggitt Sensing Systems demonstrates the intricate process of developing cable for sensors used in these situations.

Presented by: Dan Ott Web Industries Director, Business Development, Advanced Composites Market With the growth of Fiber Placement technology as a preferred automation technology in aerospace manufacturing and the rapid growth of new production line installations, it is crucial to provide material in a form which meets all necessary specifications and supports the optimum productivity available from this major capital investment made by the producer of the parts. Achieving these goals happnes when the part designer, AFP machine builder, and the slit tape producer design the best process and format which provides smooth, efficient and rapid delivery of the prepreg slit tape to the Fiber Placement laydown head. Tape size (width), slit width tolerance, spool shape and size, density of prepreg on the spool, spool change-over and handling processes all play a factor in productivity, and creating (or inhibiting) the best ROI on a full-scale AFP production line.

Abstract Introduction: This study evaluates driving ability in those with Charcot Marie Tooth Disease Type 1A, a hereditary peripheral neuropathy. Methods: Individuals with Charcot Marie Tooth Disease Type 1A (n = 18, age = 42 ± 7) and controls (n = 19; age = 35 ± 10) were evaluated in a driving simulator. The Charcot Marie Tooth Neuropathy Score version 2 was obtained for individuals. Rank Sum test and Spearman rank correlations were used for statistical analysis. Results: A 74% higher rate of lane departures and an 89% higher rate of lane deviations were seen in those with Charcot Marie Tooth Disease Type 1A than for controls (p = 0.005 and p < 0.001, respectively). Lane control variability was 10% higher for the individual group and correlated with the neuropathy score (rS = 0.518, p = 0.040), specifically sensory loss (rS = 0.710, p = 0.002) and pinprick sensation loss in the leg (rS = 0.490, p = 0.054).

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.

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.

Abstract The ability of senior citizens as well as other members of the general population to engage in an effective manner with technology is of increasing importance as new and innovative technologies become available. While recognizing the challenges that technologies can have on different populations, the ability to interact successfully with new technologies will, for seniors, have important consequences that can affect their quality of life and those of their families in numerous and important ways. This study, building upon previous research, examines the major dimensions of decision-making regarding attitudes toward autonomous vehicle technologies (ATVs) and their use. The study utilized data from a study of senior citizens in the Dallas-Fort Worth (DFW) area and compared the results with a sample of graduate students from a local university.

For over 30 years, field research and laboratory testing has consistently demonstrated that proper utilization of a seat belt dramatically reduces the risk of occupant death or serious injury in motor vehicle crashes. The injury prevention benefits of seat belts require that they remain fastened during collisions. Federal Motor Vehicle Safety Standards and SAE Recommended Practices set forth seat belt requirements to ensure proper buckle performance in accident conditions. Numerous analytical and laboratory studies have investigated buckle inertial release properties. Studies have repeatedly demonstrated that current buckle designs have inertial release thresholds well above those believed to occur in real-world crashes. Nevertheless, inertial release theories persist. Various conceptual amplification theories, coupled with high magnitude accelerations measured on vehicle frame components are used as support for these release theories.

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

Abstract Purpose: Obesity can be a contributing factor to decrease head injuries in motor vehicle collisions (MVCs). We sought to assess whether obesity is associated with decreased head injury from MVCs by sex. Methods: This study was a retrospective observational study and evaluated crash data from 1997 to 2015 obtained from the International Center for Automotive Medicine. Patients were categorized into normal, overweight, and obesity subgroups. The primary endpoint was serious head injury. Multivariate logistic regression analysis was performed, and adjusted odds ratios (AORs) of subgroups were calculated for study outcomes adjusted for any potential confounders. Results: Among enrolled 588 patients, 262 were male with 30.9% normal, 40.1% overweight, and 29.0% obesity subgroups, and 326 were female with 44.8% normal, 24.8% overweight, and 30.4% obesity subgroups.

This document describes the assessment methods and physical requirements associated with the manual handling of carts and dollies, specific to material handling systems. All possible designs and applications could not be anticipated in creating these guidelines. Where there are questions of adherence to this document, such as use of an “off-the shelf” design, always consult the responsible Ergonomics Department. Force guidelines were primarily developed referencing the push/pull psychophysical Snook data contained in A Guide to Manual Materials Handling (second edition) by Mital, Nicholson and Ayoub (NY: Taylor & Francis, 1997). The force guidelines accommodate 75% of female capabilities and 99% of male capabilities. Factors that were included in the established guideline include: push / pull distances, vertical hand height, horizontal hand height, frequency and wheel / castor alignment and load rating. These factors were used to develop a conservative force guideline.

A generalized MADYMO minor rear crash vehicle model with BioRIDII ATD was developed and validated using the mean response of previously published 12 km/h delta-V rear crash tests. BioRIDII simulation pelvis, thorax and head x-axis accelerations, as well as head y-axis angular acceleration, fell within corridors defining +/- one standard deviation of the mean BioRIDII crash test responses. Peak sagittal plane BioRIDII upper neck forces and moments in the simulation were on par with the mean values observed from the crash tests. After the model was validated for 12 km/h delta-V, the model was further exercised by performing simulations with (1) a Hybrid III 50th percentile occupant and (2) by reducing the pulse by 40% of its original value. Results indicate that this generalized minor rear crash model could be useful in accurately estimating occupant kinematics and kinetics in minor crashes up to at least 12 km/h delta-V as an alternative to expensive and time consuming crash testing.

This paper describes an effective integrated method for estimation of subject-specific mass, inertia tensor, and center of mass of individual body segments of a digital avatar for use with physics-based digital human modeling simulation environment. One of the main goals of digital human modeling and simulation environments is that a user should be able to change the avatar (from male to female to a child) at any given time. The user should also be able to change the various link dimensions, like lengths of upper and lower arms, lengths of upper and lower legs, etc. These customizations in digital avatar's geometry change the kinematic and dynamic properties of various segments of its body. Hence, the mass and center of mass/inertia data of the segments must be updated before simulating physics-based realistic motions. Most of the current methods use mass and inertia properties calculated from a set of regression equations based on average of some population.

In 2006, there were approximately 23,500 rear-end crashes involving heavy trucks (i.e., gross vehicle weight greater than 4,536 kg). The Enhanced Rear Signaling (ERS) for Heavy Trucks project was developed by the Federal Motor Carrier Safety Administration (FMCSA) to investigate methods to reduce or mitigate those crashes where a heavy truck has been struck from behind by another vehicle. Visual warnings have been shown to be effective, assuming the following driver is looking directly at the warning display or has his/her eyes drawn to it. A visual warning can be placed where it is needed and it can be designed so that its meaning is nearly unambiguous. FMCSA contracted with the Virginia Tech Transportation Institute (VTTI) to investigate potential benefit of additional rear warning-light configurations as rear-end crash countermeasures for heavy trucks.

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.

Accident statistics shows pedestrian accident fatalities as one of the important concerns globally. In view of this, new test protocols for pedestrian safety have been drafted in regulation as well as in consumer group. Also as per new ENCAP requirements, pedestrian safety assessment is used as one of the four assessment criteria's (Adult protection, child safety, pedestrian safety, safety assist) in deciding the overall vehicle safety. Hence today importance of pedestrian safety is perceived as never before in vehicle development program. Basically pedestrian safety evaluation involves subsystem level (head form, upper leg form and lower leg form) impact tests representing human body parts, at specific region on test vehicle with injury limits to decide the severity of impact. In general these injuries are governed by vehicle styling, vehicle stiffness, hard points clearances from vehicle exterior like bonnet, bumper etc.

In cold climatic regions (25°C below zero) thermal comfort inside vehicle cabin plays a vital role for safety of driver and crew members. This comfortable and safe environment can be achieved either by utilizing available heat of engine coolant in conjunction with optimized in cab air circulation or by deploying more costly options such as auxiliary heaters, e.g., Fuel Fired, Positive Temperature Coefficient heaters. The typical vehicle cabin heating system effectiveness depends on optimized warm/hot air discharge through instrument panel and foot vents, air directivity to occupant's chest and foot zones and overall air flow distribution inside the vehicle cabin. On engine side it depends on engine coolant warm up and flow rate, coolant pipe routing, coolant leakage through engine thermostat and heater core construction and capacity.

EuroSID-2 and EuroSID-2re are among the most frequently used side impact dummies in vehicle crash safety. Radioss is one of most widely applied finite element codes for crash safety analysis. To meet the needs of crash safety analysis and to exploit the potential of the Radioss code, a new generation of EuroSID-2 (ES2) and EuroSID-2re (ES2_RE) Radioss dummies was developed at First Technology Safety System (FTSS) in collaboration with Altair. This paper describes in detail the development of the ES2/ES2_RE dummies. Firstly whole dummy meshes were created based on CAD data and intensive efforts were made to obtain penetration/intersection-free models. Secondly FTSS finite element certificate tests at component level were conducted to obtain satisfactory component performances. These tests include the head drop test, the neck pendulum test, the lumbar pendulum test and the thorax drop test [ 1 , 2 ].

A comprehensive research is presented aiming at assessing the ride comfort of subjects seated into road or off-road vehicles. Although many papers and books have appeared in the literature, many issues on ride comfort are still to be understood, in particular, the paper investigates the mutual effects of the posture and the vibration caused mostly from road unevenness. The paper is divided into two parts. In the first part, a mathematical model of a seated subject is validated by means of actual measurements on human subjects riding on a car. Such measurements refer to the accelerations acting at the subject/seat interface (vertical acceleration at the seat cushion and horizontal acceleration at the seat back). A proper dummy is used to derive the seat stiffness and damping.