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Highway safety remains a significant concern, especially in mixed traffic scenarios involving heavy-duty vehicles (HDV) and smaller passenger cars. The vulnerability of HDVs following closely behind smaller cars is evident in incidents involving the lead vehicle, potentially leading to catastrophic rear-end collisions. This paper explores how automatic speed enforcement systems, using speed cameras, can mitigate risks for HDVs in such critical situations. While historical crash data consistently demonstrates the reduction of accidents near speed cameras, this paper goes beyond the conventional notion of crash occurrence reduction. Instead, it investigates the profound impact of driver behavior changes within desired travel speed distribution, especially around speed cameras, and their contribution to the safety of trailing vehicles, with a specific focus on heavy-duty trucks in accident-prone scenarios.

Automatic emergency braking and forward collision warning (FCW) reduce the incidence of police-reported rear-end crashes by 27% to 50%, but these systems may not be effective for preventing rear-end crashes with nonpassenger vehicles. IIHS and Transport Canada evaluated FCW performance with 12 nonpassenger and 7 passenger vehicle or surrogate vehicle targets in five 2021-2022 model year vehicles. The presence and timing of an FCW was measured as a test vehicle traveling 50, 60, or 70 km/h approached a stationary target ahead in the lane center. Equivalence testing was used to evaluate whether the proportion of trials with an FCW (within ± 0.20) and the average time-to-collision of the warning (within ± 0.23 sec) for each target was meaningfully different from a global vehicle car target (GVT).

Lane changing is an essential action in commercial vehicles to prevent collisions. However, steering system malfunctions significantly escalate the risk of head-on collisions. With the advancement of intelligent chassis control technologies, some autonomous commercial vehicles are now equipped with a four-wheel independent braking system. This article develops a lane-changing control strategy during steering failures using torque vectoring through brake allocation. The boundaries of lane-changing capabilities under different speeds via brake allocation are also investigated, offering valuable insights for driving safety during emergency evasions when the steering system fails. Firstly, a dual-track vehicle dynamics model is established, considering the non-linearity of the tires. A quintic polynomial approach is employed for lane-changing trajectory planning. Secondly, a hierarchical controller is designed.

For the design optimization of the electric bus body frame orienting frontal crash, considering the uncertainties that may affect the crashworthiness performance, a robust optimization scheme considering tolerance design is proposed, which maps the acceptable variations in objectives and feasibility into the parameter space, allowing for the analysis of robustness. Two contribution analysis methods, namely the entropy weight and TOPSIS method, along with the grey correlation calculations method, are adopted to screen all the design variables. Fifteen shape design variables with a relatively high impact are chosen for design optimization.

The accuracy of collision severity data recorded by event data recorders (EDRs) has been previously measured primarily using barrier impact data from compliance tests and experimental low-speed impacts. There has been less study of the accuracy of EDR-based collision severity data in real-world, vehicle-to-vehicle collisions. Here we used 189 real-world front-into-rear collisions from the Crash Investigating Sampling System (CISS) database where the EDR from both vehicles recorded a severity to examine the accuracy of the EDR-reported speed changes. We calculated relative error between the EDR-reported speed change of each vehicle and a speed change predicted for that same vehicle using the EDR-reported speed change of the other vehicle and conservation of momentum. We also examined the effect of vehicle-type, mass ratio, and pre-impact braking on the relative error in the speed changes.

Building upon prior research, this paper compares computer simulations to a previously conducted rollover crash test of a tractor-semitrailer. The effects of torsional stiffness were elucidated during the correlation of simulations to the rollover test. A commercially available vehicle dynamics and reconstruction software was used for the simulation. Unique aspects of the rollover crash test were modeled in the simulation. A tractor-semitrailer quarter-turn rollover crash test conducted by IMMI was reconstructed using impact and vehicle dynamics models within the simulation software HVE (Human, Vehicle & Environment). The SIMON (SImulation MOdel Non-linear) module and the DyMESH (Dynamic MEchanical SHell) module within HVE were used. During the IMMI test, onboard instrumentation recorded acceleration and roll rate data in six degrees of freedom to characterize both tractor and semitrailer dynamics before and during the rollover event.

This SAE Standard applies to all forestry machines exposed to the hazard of objects penetrating the front of the operator station (other than the roof). This would include:

The design and analysis of the roll cage for the ATV car are the subjects of this report. The roll cage is one of the key elements of an ATV car. It is the primary component of an ATV, on which the engine, steering, and gearbox are mounted. The vehicle's sprung mass is beneath the roll cage. The initiation of cracks and the deformation of the vehicle are caused by forces acting on it from various directions. Stresses are consequently produced. FEA of the roll cage is used in this paper in an effort to identify these areas. We have performed torsional analysis as well as front, rear, side impact, and rollover crash analyses. These analyses were all completed using ANSYS Workbench 2020 R1. The design process complies with all guidelines outlined in the SAE rule book of E-Baja.

The passive safety performance of a child seat is modulated by the design features of the child seat and the vehicle interior. For example, in the rear-facing configuration, the child seat impacting front structures increases the head injury risk during a frontal crash. Therefore, this study evaluates the effectiveness of the load leg countermeasure in improving the child seat's overall kinematics and its capability to prevent the secondary impact on the vehicle interior structure in a severe frontal crash scenario. An in-depth, real-world crash investigation involving a properly installed rear-facing child seat impacting the center console was selected for the study where the infant sustained a severe brain injury. In addition, this crash is employed to choose the crash parameters for evaluating the effectiveness of the load leg countermeasure in a similar scenario.

Child crash injury protection in severe rear impact chiefly depends on how well the rear survival space bounded by the vehicle structure is maintained. Previous research and studies have shown the ill effects of front seatback collapse intruding into the rear child survival space from front with minor or no intrusions from the rear. This paper shows the child injury pattern and fatal injury mechanism for a rear impact crash with a severe compartment intrusion from the rear without any front seat occupant. Furthermore, it compares the injury outcome with a similar crash and severe intrusion in the presence of the front occupant employing a full-scale vehicle-to-vehicle crash test. A detailed real-world crash investigation is conducted to identify the injury mechanism and is compared with the outcome of similar severity rear impact vehicle-to-vehicle crash tests producing different injury patterns.

Abstract Parking an articulated vehicle is a challenging task that requires skill, experience, and visibility from the driver. An automatic parking system for articulated vehicles can make this task easier and more efficient. This article proposes a novel method that finds an optimal path and controls the vehicle with an innovative method while considering its kinematics and environmental constraints and attempts to mathematically explain the behavior of a driver who can perform a complex scenario, called the articulated vehicle park maneuver, without falling into the jackknifing phenomena. In other words, the proposed method models how drivers park articulated vehicles in difficult situations, using different sub-scenarios and mathematical models.

This work aimed to analyze the behavior of the rear structure region of an electric bus in a rear collision situation and to create mechanisms capable of absorbing the energy generated by the impact, to guarantee the integrity of the batteries. These, when damaged in a collision, can release different types of flammable electrolytes, and even start a fire, creating a great risk to passengers and other people near to the vehicle. For this purpose, an impact absorber was developed to protect the batteries. Studies were carried out on rectangular cross-section profiles for programmed deformation, known as crash boxes (which aim to convert kinetic energy into deformation energy). Proposals were created based on concepts obtained in the literature and numerically evaluated through explicit numerical simulations based on other similar articles. From these studies it was possible to obtain higher values of energy absorption when compared to a square tube of the same cross-section.

In order to evaluate the THOR-50M as a front impact Anthropomorphic Test Device (ATD) for vehicle safety design, the ATD was compared to the H3-50M in matching vehicle crash tests for 20 unique vehicle models from 2 vehicle manufacturers. For the belted driver condition, a total of fifty-four crash tests were investigated in the 56.3 km/h (35 mph) front rigid barrier impact condition. Four more tests were compared for the unbelted driver and right front passenger at 40.2 km/h (25 mph) in the flat frontal and 30-degree right oblique rigid barrier impact conditions. The two ATDs were also evaluated for their ability to predict injury risk by comparing their fleet average injury risk to Crash Investigation Sampling System (CISS) accident data for similar conditions. The differences in seating position and their effect on ATD responses were also investigated.

Motor grader is self-propelled, versatile machine widely used for road construction and maintenance in mining and construction applications. It required working in rugged terrain with uneven and slippery surfaces. Probability of rollover in motor grader is more due to the vehicle profile and high centre of gravity. In light of the above, Roll over Protective Structure (ROPS) is essential to safe guard the operator from any fatal injuries / life during the operation of the equipment at different terrain conditions. Considering DGMS (Directorate of General Mines and safety) requirements, a rugged two post Rollover Protective Structure (ROPS) was designed as per ISO 3471 criteria for ROPS and Falling object Protection Structure (FOPS) as per ISO 3449 Material selection for ROPS and FOPS is one of significant factor in design process by meeting the design criteria. It should have dual characteristic, firstly, it is expected to tough enough to withstand sudden impact forces.

The coefficient of restitution is utilized in various methods for determining the change in velocity (delta-V) associated with a vehicle collision event. Additionally, for a given delta-V, the magnitude of vehicle acceleration varies with different collision pulse durations. Collision restitution and duration parameters are thus considered by both accident reconstructionists and biomechanists in the investigation of vehicle collision severity and occupant injury potential. Because of the uniqueness of individual vehicle designs, it is difficult to determine a collision’s specific coefficient of restitution and crash pulse duration. Accident reconstructionists often estimate the values of these parameters based on staged crash tests. Prior studies involving low-speed collisions have sought to determine correlations between restitution and collision characteristics and have established equations to assist in estimating restitution.

This study focused on occupant responses in very large pickup trucks in rollovers and was conducted in three phases. Phase 1 - Field data analysis: In a prior study [9], 1998 to 2020 FARS data were analyzed; Pickup truck drivers with fatality were 7.4 kg heavier and 4.6 cm taller than passenger car drivers. Most pickup truck drivers were males. Phase 1 extended the study by focusing on the drivers of very large pickup trucks. The size of 1999-2016 Ford F-250 and F-350 drivers involved in fatal crashes was analyzed by age and sex. More than 90% of drivers were males. The average male driver was 179.5 ± 7.5 cm tall and weighed 89.6 ± 18.4 kg. Phase 2 – Surrogate study: Twenty-nine male surrogates were selected to represent the average size of male drivers of F-250 and F-350s involved in fatal crashes. On average, the volunteers weighed 88.6 ± 5.2 kg and were 180.0 ± 3.2 cm tall with a 95.2 ± 2.2 cm seated height.

This SAE Standard establishes the maximum gradient rating during hopper discharge of self-propelled, driver-operated sweepers and scrubbers as defined by SAE J2130-1 and SAE J2130-2.