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• It is the first known study examining pedestrian crash types and vehicle types. • Larger passenger vehicles were more likely to hit pedestrians in two scenarios. • The first was when turning at intersections. • The second was when pedestrians were on or near travel-lane edges at nonintersections. • Findings suggest pedestrians near front corners of larger vehicles difficult to see. • More research is needed to examine A-pillar blind zones by vehicle type. Introduction: This is the first known study that examines the association between common pedestrian crash types and passenger vehicle types. Method: The analysis included single-vehicle, single-pedestrian crashes from two data sets: North Carolina state crash data and the Fatality Analysis Reporting System (FARS). We performed separate multinomial logistic regression analyses of major pedestrian crash types occurring at or near intersections and at nonintersections. Results: At or near intersections, minivans, large vans, pickups, and SUVs (collectively known as light truck vehicles, or LTVs) were more likely than cars to be involved in crossing-roadway–vehicle-turning-left crashes versus crossing-roadway–vehicle-not-turning crashes. LTVs were also more likely involved in fatal crossing-roadway–vehicle-turning-right crashes at or near intersections versus crossing-roadway–vehicle-not-turning crashes when compared with cars. At nonintersections, LTVs were associated with increased odds of walking-along-roadway crashes relative to crossing-roadway–vehicle-not-turning crashes when compared with cars. Conclusions: LTVs were more likely to be involved in certain pedestrian crash types, implying a potentially problematic visibility of pedestrians near the front corners of these vehicles. Practical applications: More research is needed to examine A-pillar blind zones by vehicle type. If it is found that LTVs have larger blind zones, automakers should consider ways to design the A-pillars of these vehicles to minimize blind zones while maintaining pillar strength. Doing this could improve pedestrian safety around these increasingly popular larger vehicles. [ABSTRACT FROM AUTHOR]

Firstly, the MBD (multi-body dynamics) model of the whole vehicle is built according to the measured vehicle parameters. Then, the road spectra acquisition test is carried out. Under the test road conditions, the acceleration, displacement, and force signals of multiple positions of the whole vehicle are collected. Taking the road test signals as the iterative target and the vehicle MBD model as the iterative carrier, the vehicle equivalent excitation is obtained by using the VIM (virtual iteration method). By applying the equivalent excitation obtained by VIM to the vehicle MBD model, the load spectra of key points of the driving rear axle are obtained. The accuracy of the model is verified by comparing the measured signals with the iterative signals, and the reliability of the key points load spectra is enhanced. Secondly, the FEA (finite element analysis) model of the rear axle is built, and the static analysis results of each key point under unit load are obtained with the help of FEA software. Thirdly, the FEA results, key points load spectra, and material fatigue characteristic curve of the rear axle are input into the fatigue software to conduct the fatigue simulation of the rear axle. According to the fatigue analysis results, the position where the fatigue life does not meet the set goal is accurately located. Finally, the structure is optimized based on the above results. The fatigue life evaluation of the optimized rear axle shows that its durability has been significantly improved. [ABSTRACT FROM AUTHOR]

Aiming at the problem of door opening caused by the unlocking of the side door latch system under the action of inertial force when the car is in a side impact, this paper takes a light truck door latch as the research object, and proposes an inertia load resistance analysis method combining theoretical calculation and simulation analysis. Through the theoretical calculation of inertia load resistance of the door latch, the force of each part and the rotation of the pawl are analyzed. We perform inertia load resistance simulation analysis on the latch to verify the reliability of the theoretical calculation results. If the theoretical calculation result is that the latch will be unlocked under the inertia load of 60 g (588 m/s2), we compare the force of each part in the theoretical calculation process with the normal opening condition of the latch to provide a basis for the optimization of the latch structure. Finally, theoretical calculations and a simulation analysis are carried out on the optimized results again, and a latch structure that meets the requirements of the inertia load resistance is obtained. Since the results obtained from the inertia load resistance simulation analysis are basically consistent with the theoretical calculation results of the inertia load resistance and the inertia load resistance simulation requires a lot of computing time, after the verification of the inertia load resistance simulation analysis, firstly, the inertia load resistance simulation step can be omitted in the subsequent structural optimization process. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The most critical accidents are generally found by the side impact crashes in automotive and more than 30% loss of life due to road accidents using passenger cars and light trucks. Various assemblies introduced to attain safety by sidebars, crumple zones, crash cones and energy absorbing padding. But during event of crashes, generally foam used to absorb energy and also set to dummy motion. When vehicle hit on another vehicle, initially dummy thrown towards impacting vehicle, then pelvis of dummy hits doors panel and at this time foam will absorb impacting energy and helps dummy to move on opposite directions. The padding usually applied and located in the vehicle door for securing the pelvis, the abdomen and thorax area. The proposed work presented behaviors of polyurethane foam padding by quasistatic compression testing and observed under impact in simulated environment. Different combinations of foam material along with various density used for compression testing by universal testing machine. At last, composite polyurethane foam block III found as highly efficient energy absorber composite polyurethane foam for side impact crash. Hyper mesh used for meshing and LS Dyna represented material model inputs for dynamic impact testing. [ABSTRACT FROM AUTHOR]

An active driver support system for parking maneuvers is described. The market for such systems is reviewed. An operational algorithm is outlined for the proposed system. Methods are described for calculating the vehicle position, locating a parking spot, and generating a parking trajectory. The system undergoes tests in the CARLA simulator, and field tests of a prototype vehicle are conducted on a specially equipped testing ground. [ABSTRACT FROM AUTHOR]

More attention should be given to bicycle-motor vehicle (BMV) crashes, as cyclists are at a higher risk of suffering injuries than motor vehicle users in a crash. This study aims to explore the factors influencing the injury severity of bicycle-motor vehicle (BMV) crashes in Beijing (China) and discusses the commonalities and differences between the urban and suburban areas. Information regarding 1,136 crashes between bicycles and motor vehicles were collected using police reported data from 2014 to 2015. A two-stage approach integrating random parameters logit (RP-logit) model and two-step clustering (TSC) algorithm was proposed to investigate the significant influence factors and their combination characteristics. Specifically, the RP-logit model was first used to identify the significant influence factors of urban and suburban areas, and then the TSC algorithm was applied to reveal the combination characteristics of significant influence factors for the fatal crashes. Five factors were found to be statistically significant and had random effects on the injury severity in urban areas, i.e., type of motor vehicle, motor vehicle license ownership, type of bicycle, signal control mode and lighting condition; and seven factors were found to be statistically significant on the injury severity in suburban areas, i.e., type of motor vehicle, motor vehicle license ownership, physical isolation facility, signal control mode, weather, visibility and lighting condition. Based on TSC, the combination of significant factors showed different characteristics for fatal crashes in urban and suburban areas, in which two types of the scene including five factors should be concerned in urban areas while one type of scene containing four factors in suburban areas. The results suggest that different influence factors and individual heterogeneity exist in the RP-logit model for injury severity analysis of BMV crashes in urban and suburban areas. It shows that in urban areas, heavy truck, light truck and bus significantly increase the likelihood of fatal injury than that of suburban areas. These findings can provide valuable reference information for BMV crashes response, such as heavy truck restriction, to facilitate regional safety measures for urban and suburban areas. [ABSTRACT FROM AUTHOR]

The aim of this research is to develop a semi-active secondary suspension system equipped with magnetorheological dampers to reduce the amplitude of vibrations and shocks to sensitive payloads in the cargo section of road trucks. First, a double-ended magnetorheological damper was modeled, designed, and built for use in a secondary suspension system of light trucks. Next, a pallet with a secondary suspension system consisting of four magnetorheological dampers was constructed to be installed on the load side of the light truck. Then, the behavior of the system was examined by testing it by passing the vehicle on the speed-bump profile. By performing dynamic tests with harmonic excitation on the damper, the results showed that the maximum damping force with the electric current of 2 Amp is increased 11.6 times compared to 0 Amp. Furthermore, by using the forces obtained from the Spencer model in predicting the dynamic behavior of the damper with an average relative error of %1.49 compared to the force obtained from the experimental test and implementing the two-dimensional model of the half-truck, the performance of the system in passing the speed-bump profile was investigated. The results of simulations and experimental tests showed that with increasing electric current intensity from 0 to 2 Amp, the maximum amplitudes of the sensitive payload decreased in passing the speed-bump %43.6 and %32.4 in simulations and experimental tests compared to the situation without the secondary suspension system respectively. [ABSTRACT FROM AUTHOR]

Background: Pedestrian and bicyclist injuries and fatalities have increased since 2010 after a long downward trend. Trucks and SUVs, collectively called light trucks, have also increased in sales and size, which may affect pedestrians and bicyclists. Additionally, pedestrian and cyclist commuters vary by state and it has been speculated that an increase in such commuters may affect fatalities. Studying vulnerable road users can bestow clues on best practices for infrastructure and public health. Methods: State level pedestrian and cyclist fatality data was obtained from the National Highway Transportation Safety Administration for 2018. Light truck registration by state was obtained from the Office of Highway Policy Information for 2018. Commuters who walk or bike to work were obtained from the American Community Survey from 2009 to 2011, from the latest Centers for Disease Control report. We performed multiple linear regression, accounting for total motor vehicle lane miles per 100 people, also obtained from the Office of Highway Policy Information for 2018. Multiple regression analysis was performed to assess predictors for pedestrian and cyclist fatalities with the predictors variables of light truck registration, lane miles per 100 people, and proportion of commuters who are vulnerable road users. Secondary analysis included simple linear regression of the predictor variables against each other. Results: The multiple regression model, including proportion of light truck registration, lane miles per 100 people, and proportion of commuters who are vulnerable road users, accounted for 18% of the variability in the outcome variable (p = 0.03). An increased number of vulnerable road users were negatively associated with pedestrian and bicyclist fatality. Additionally, there appeared to be an association between motor vehicle lane miles per 100 people and proportion of light truck registrations that was also significant (p < 0.01). Conclusion: The variables affecting vulnerable road user deaths are important to understand given their increased risk exposure on the road. This state level study identifies a potential protective variable with increased vulnerable road users being associated with a decrease in pedestrian and bicyclist death rates. Additionally, light truck proportions do not appear to have a significant effect on death rates. [ABSTRACT FROM AUTHOR]

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the discrete adjoint approach with the grid deformation technique based on radial basis function was presented to solve the tough problem that the complex shape of the defrosting duct is very difficult to be optimized with multiple parameters in the improvement of the defrosting performance of vehicle. Firstly, the defrosting performance of a light truck was analyzed. Then the discrete adjoint approach was applied by taking the average Nusselt-number as the objective function. The normal surface sensitivity was used in the deformation of the defrosting duct. After 10 optimization cycles, the optimal model was acquired. The results show that, after optimization, the sum of the average Nusselt-number is increased from 3164.16 to 3350.54, which has a positive effect on improving the convection and heat transfer capacity on the windshield effectively. Compared with the initial model, the airflow of the outlet near the windshield is increased from 95.07 g/s to 96.94 g/s, the defrosting time required by the optimal model is reduced by more than 20s. Therefore, the discrete adjoint approach can optimize the complex shape of defrosting duct with multiple parameters effectively, which provides an effective method in the study of automobile defrosting performance. [ABSTRACT FROM AUTHOR]