Rollover Accidents Research Articles

Evaluation of SSF, Roof Crush Test as an Alternative to Dynamic Rollover Test using Numerical Approach

Rollover accidents are classified into various scenarios, and with the increasing prevalence of high-centre-of-gravity (CG) vehicles in Southeast Asia (SEA) particularly in Malaysia, such as SUVs, MPVs and pickup trucks; assessing vehicle rollover risk has become critical. Even though rollover incident recorded low number of cases compared to other crash types in Malaysia, it had the highest casualty index for killed or seriously injured (KSI) and the situation induces worries because majority of the fatalities in rollover crashes among passenger vehicle occupants goes to high CG vehicle type. There are several limitations from the SEA nations to enforce costly dynamic rollover test as safety specification for SEA market requirement. Therefore, this study aims to evaluate Static Stability Factor (SSF), and roof resistance test (FMVSS 216), as an alternative to the dolly rollover test (FMVSS 208) using Finite Element Analysis (FEA). A correlated Chevrolet Silverado MY 2014 model is employed, with different SSF values representing varying levels of vehicle stability. The study evaluates peak force, peak energy absorption, and maximum intrusion during rollover simulations according to FMVSS 208 for vehicle models with different SSF values. Results indicated that vehicles with lower SSF values lead to higher energy absorption and intrusion, signifying increased rollover impact. Additionally, the article suggests that FMVSS 216 Roof Resistance Test is more severe than FMVSS 208 and vehicle rating system based on SSF value is vital for market awareness. Understanding the vehicle structural integration in rollover scenarios is essential for improving safety measures and vehicle design, especially for high-centre-of-gravity vehicles prevalent in the market.

Optimization study of tail-lateral occupant injury and restraint system for an off-road vehicle ramp rollover

The process of rollover accidents involving specialized vehicles is characterized by intense motion and long duration. Although these accidents are infrequent, they often lead to a high fatality rate. In this study, we utilized LS-Dyna software to simulate the rollover of a vehicle on a side ramp. This simulation aimed to verify the reliability of our model establishment by comparing the vehicle’s motion attitude and center-of-mass acceleration with experimental results. Additionally, we sought to investigate the lateral occupant injuries that occur in the tail section of a certain type of specialized vehicle during a rollover. Initially, we obtained the vehicle’s motion trajectory and the dummy’s motion state through simulation. Subsequently, we extracted the injury response of each part of the dummy. We then simplified the entire vehicle model and made improvements to the occupant restraint system, ultimately designing an enhanced system. Finally, we approximated and replaced the entire vehicle model by establishing an approximation model. We combined this with an optimization algorithm to optimize the occupant restraint system. The simulation results demonstrate that the improved occupant restraint system significantly reduces the axial force on the neck of the occupant and the comprehensive evaluation index of injury. Furthermore, the simulation results for each component fall below the injury limit value specified in the FMVSS208 crash occupant protection standard. Therefore, the improved occupant restraint system proposed in this study effectively mitigates lateral occupant injury during rollover accidents.

Development of an Anti-rollover Warning and Active Intervention Controller for Wheeled Tractor

Background: Tractor rollover accidents are the most severe problem in agricultural production. According to the statistical analysis of the rollover incidents, some rollover accidents can be avoided by timely anti-rollover warning and active control. There are a few researches on the anti-rollover control for agricultural tractors, although great progress in the research on tractor security has been achieved, such as rollover protective structure design. Objective: The purpose of this patent study was to develop a controller with the function of warning as well as active anti-rollover control employing the power motor installed on the steering column to adjust the front wheel angle and control the rollover index within the safety range. Methodology: The structure block for the hardware of the controller was devised that included data obtaining, rollover risk estimation, rollover warning, and front-wheel steering control sections. The main circuits have been designed in detail by adopting module methods, such as motor control circuit, positioning and transmission circuit, etc. The control scheme has been demonstrated by designing an overview of the overall architecture, including rollover indicator calculation, load transfer ratio (LTR) controller design, and front-wheel steering angle tracking controller design. C language has been used to accomplish the software design. Results: The active anti-rollover controller can calculate and keep the LTR within the stable range by adjusting the front wheel angle in real-time. The fast response and smoothness of the results demonstrate that the controller can fulfill the designed function. Conclusion: The developed controller can meet the control requirement due to several advantageous aspects, such as reliability, effectiveness, and practicability. It is prospective for the developed controller to provide a valuable reference to reduce tractor rollover accidents.

Driving adaptability of highway steel-concrete composite beam bridge with multiple damages: theory, technology and practice

ABSTRACT To enhance the post-disaster highway driving speed evaluation system for steel-concrete composite beam bridge (SCCBB), a human-vehicle-bridge coupled driving adaptability analysis method is proposed. This method integrates considerations of both driving safety and comfort. Numerical simulation is employed to utilize a damaged SCCBB as the engineering context for studying vehicle rollover safety, vibration acceleration limits, and driving comfort. The analysis considers various vehicle types, including sedan cars, mini vans, motor buses, and trucks, resulting in recommended speed limits for each category. The study reveals that trucks demonstrate lower susceptibility to rollover accidents compared to sedan cars, mini vans, and motor buses under constant damage grade and vehicle speed conditions. However, increased damage grade and road surface roughness elevate rollover risks and diminish driver comfort. To ensure smooth post-disaster traffic flow on SCCBB and maintain acceptable driving comfort and speed levels, it is recommended to enforce speed limits: below 60 km/h for sedan cars, below 40 km/h for mini vans and motor buses, and below 80 km/h for trucks. The primary aim of this study is to provide technical guidance for the safe operation and maintenance of post-disaster SCCBB.

Effects of Transition Curves and Superelevation on the Critical States of Truck Rollovers on Sharp Curves

Sharp curves are vulnerable sections for rollover accidents. This study was conducted to investigate the effects of transition curve and superelevation on the critical speed and critical braking distance of truck rollovers. Using different transition types (spiral, Bloss and Grabowski curve) and different superelevation values (6%, 120 m transition length and 8%, 160 m) as variables, experiments of constant speed driving and hard braking were simulated and conducted by Trucksim. Conclusions regarding the influence of these road design factors on the stability of vehicles were then proposed. Grabowski curve allowed for the maximum critical rollover speed. The difference in critical rollover speed between different transition types was only determined by the length of the transition section. Simply extending the length of the transition section increased the critical rollover speed of spiral curve, at the same time decreasing the critical speed of Bloss and Grabowski curve. Hard braking experiments showed completely different characteristics. As the initial speed increased, only spiral curve became safer. Increasing superelevation made the braking behaviour of the vehicle more dangerous and fraught with uncertainties due to different target speed, starting curvature and changing superelevation. Based on these findings, a number of useful recommendations for drivers and road designers were put forward.

Enhancing Tractor Stability and Safety through Individual Actuators in Active Suspension

Tractor overturning accidents are a prominent safety concern in the field of agriculture. Many studies have been conducted to prevent tractor overturning accidents. Rollover protective structures and seat belts currently installed on tractors cannot prevent them from overturning. The posture of a tractor was controlled by installing individual actuators. The overturning angles of the tractor equipped with an actuator were compared with those of a tractor with no actuator. For the overturning angles in all directions of the tractor, it rotated 15° from 0° to 345°, and the actuator height suitable for the tractor posture was controlled by establishing an equation according to the tractor posture. Consequently, posture control using actuators was noticeably improved. This study proposes that tractors operating on irregular and sloping terrain be equipped with individual actuators. These results prevent tractor rollover accidents and improve safety and driving stability.

The pattern of maxillofacial fractures associated with rollover accidents: A 7-year retrospective study.

This study aimed to assess the incidence and pattern of maxillofacial fractures and related demographic data in the victims of rollover crashes. This retrospective study was based on medical records of patients who sustained maxillofacial injuries following rollover accidents. Investigated data included age, gender, accident date and time, accident cause, seat belt usage, airbag deployment, road type, anatomical location of the facial fracture, and treatment approach. Among the 147 patients who met the inclusion criteria, the most prevalent age groups were 20-30 (36.7%) and 30-40 (32.7%) years, with a mean age of 33.6 ± 9.7 years. The male-to-female ratio was 6:1. Most crashes occurred in March, August, and July. These accidents involved 69.4% light vehicles and 39.6% heavy vehicles. The leading causes of rollover crashes were speeding (58.5%) followed by distracted driving (21.1%) and traffic rule violations (13.6%). The most prevalent injuries were fractures of the maxillary sinus wall (40.8%), nasal bones (39.5%), zygomaticomaxillary complex (36.1%), and the mandible (32.6%). Surgical intervention was necessary for 44.2% of patients, while 12.9% of cases underwent close reduction, and 42.9% did not require any surgical intervention. The occurrence of nasal bone fractures was significantly lower in cases where seat belts were worn and zygomatic arch fractures were less frequent in incidents with airbag deployment. In rollover crashes, the midface is the most vulnerable anatomical location. Utilization of seat belts and airbag deployment has the potential to prevent nasal bone and zygomatic arch fractures.

Development of Numerical Simulation Techniques for the Analysis of a Rollover Tractor

AbstractOne of the leading causes of death in the word is the injury in the field of agriculture. Agricultural machinery, in fact, is very dangerous for workers and rollover accidents are due to several reasons. First, it must be considered that these machines operate on nonlinear land and on extremely steep slopes, so the causes are due to operational, tractor, and soil characteristics. Furthermore, recent studies have shown that in 33% of the rollovers that are analyzed, passive safety devices, such as seat belt, are not used by workers (who got thrown out of the safety zone). Another cause of fatal accidents is that, until now, the mechanical design of tractors has not provided for occupant protection. In fact, there are no standard tests that assess the safety of the occupant. This study aims to conduct an explicit finite element (FE) analysis of a rollover test of a generic T5 category tractor to assess the structural characteristics and the biomechanical performance of the occupant.

Three-Dimensional In-Depth Dynamic Analysis of a Ground Vehicle Experiencing a Tire Blowout

<div>To investigate the effect of a tire blowout (TBO) on the dynamics of the vehicle comprehensively, a three-dimensional full-vehicle multibody mathematical model is developed and integrated with the nonlinear Dugoff’s tire model. In order to ensure the validity of the developed model, a series of standard maneuvers is carried out and the resulting response is verified using the high-fidelity MSC Adams package. Consequently, the in-plane, as well as out-of-plane dynamics of the vehicle, is extensively examined through a sequence of TBO scenarios with various blown tires and during both rectilinear and curvilinear motion. Moreover, the different possible inputs from the driver, the road bank angle, and the antiroll bar have been accounted for. The results show that the dynamic behavior of the vehicle is tremendously affected both in-plane and out-of-plane and its directional stability is degraded. It has been also found that a vehicle subjected to a TBO accident is prone to a fatal rollover accident due to the excessive lateral acceleration triggered by the TBO. Furthermore, the reaction from the driver plays a crucial role in stabilizing/destabilizing the vehicle following a TBO.</div>

자율주행과 안전 기능을 지니는 퍼스널 모빌리티 스쿠터 개발

This study developed a personal mobility scooter with autonomous driving and safety functions. The scooter can recognize indoor and outdoor environmental conditions by applying various sensor systems similar to semi-autonomous vehicles. The addition of an autonomous driving function ensures user convenience. The mobility scooter was developed to provide user safety by preventing collisions and rollover accidents. First, the system configuration and functions of the personal mobility scooter have been introduced, followed by the application of algorithms to implement each function. In terms of convenience, the main features of personal mobility scooters include indoor autonomous driving, outdoor semi-autonomous driving, and guardian-following driving. In terms of safety, the salient features are collision prevention and rollover prevention. The functions proposed here were incorporated in an actual mobility scooter, and its efficacy was verified through experiments.

Research on Rollover Stability and an Anti-Rollover Warning System for the Vibroseis Truck

Vibroseis trucks are in danger of rollover during the steering process, which severely threatens the safety of the drivers and the equipment. Therefore, it is important to examine approaches to increase the anti-rollover ability of vibroseis trucks. According to the structural characteristics and working field of the vibroseis truck, an analysis of the influence of different factors on its rollover stability was carried out. Then, a rollover warning index and an anti-rollover warning system were established, which can achieve four levels of judgment of different driving states. A simulation analysis of the anti-rollover warning system was conducted with MATLAB/Simulink software. The results showed that this warning system could accurately determine the driving state on a flat road and a sloping road and produce four types of sound–light alarm according to different rollover states. At the same time, the vibroseis truck showed poor roll stability in the slope steering process which is more prone to rollover accidents. This study establishes a foundation for further research on the design of warning systems not only for vibroseis trucks but also for other articulated trucks.

Analysis of Front Roof Header of Vehicle for Rollover Protection by using Ansys Software

Abstract: Inadequate roof strength in vehicles is a major concern as it greatly increases the risk of head and neck injuries for passengers involved in even minor rollover accidents. Despite this, many manufacturers continue to produce cars with inadequate roof strength. Rollover accidents are unfortunately quite common and often result in serious injuries, such as spinal and neck trauma. Even when wearing a seatbelt, front seat passengers can still be at risk of injury as they may be thrown from the vehicle or experience significant forces during the rollover. The key to reducing these risks lies in ensuring that the roof of the vehicle is strong enough to withstand the compressive forces of a rollover and provide enough living space for the occupants. While airbags and seat belts are important safety features, a strong roof is equally essential to protecting passengers. For this reason, we have undertaken a project to improve the strength of the front roof header in order to enhance the safety of vehicle occupants.

Impact of Non-Automobile Rollover Accidents on Patient Outcomes at an Appalachian Level I Trauma Center.

The objective of this study was to evaluate outcomes of patients involved in rollover accidents in non-automobile vehicles in a rural level I trauma center. This was a retrospective study including a total of 127 patients over 5years who were admitted to our level I trauma center following rollover accidents in either of the following: ATV, lawnmower, or tractor. Patients were significantly older in the tractor and lawnmower rollover groups, and patients less than 65years old were significantly more likely to sustain an injury in a rollover accident when compared to those greater than 65. Patients with extremity fractures secondary to tractor rollovers were more likely to be older, and patients who sustained spinal injuries secondary to tractor rollovers were more likely to be younger. Non-automobile rollovers have the potential to cause traumatic injuries; however, there does not appear to be 1 vehicle type that is more prone to injury.

Experiments to support the improvement of the integrity and resistance of the bus bodywork in a rollover accident

Experiments to support the improvement of the integrity and resistance of the bus bodywork in a rollover accident

The effect of velocity on the ability to rollover of the tractor semi-trailer when turning

This paper aims to investigate the impact of vehicle velocity on the rollover stability of a fully loaded tractor semi-trailer during lane changes and turning. Specifically, the study focuses on velocities ranging from 30 km/h to 60 km/h. The investigation found that vehicle velocity is a critical parameter that can affect the potential for rollover during lane changes or turning. The results showed that to ensure the vehicle moves steadily and does not roll over during these maneuvers, the steering angle must be controlled and kept within certain limits. The study provided specific recommendations for maximum steering angles at different velocities. For instance, to ensure stability when the vehicle is moving at 60 km/h, the maximum steering angle should be less than 4 degrees. Similarly, at 50 km/h, the maximum steering angle is recommended to be less than 6 degrees, and at 44 km/h, it should be less than 8 degrees. At lower speeds, the recommended maximum steering angle increases, with the maximum recommended angle at 36 km/h being 12 degrees. These findings highlight the importance of carefully controlling vehicle velocity and steering angle to minimize the risk of rollover accidents. By providing specific recommendations for different velocities, this study can inform the design and safety testing of vehicles to improve their stability and safety during lane changes and turning.

Tractor Rollover Accidents: A Review of Factors and Safety Measures

This paper focuses on tractor rollovers because they account for more than half of all the tractor-related deaths. As per international Labour organization more than 1247 deaths happen annually and more than 60,000 people get seriously injured due to tractor rollover. In addition, farm tractor operational safety principles are also highlighted. It has been observed through this study that the tractor rollovers occur when a tractor tips over, potentially crushing the operator. Furthermore, rollovers can happen on any terrain, but they are more likely to occur on sloping ground or when making sharp turns at high speed. Other factors that can contribute to rollovers include hitting obstacles, improper use of implements, and not using a rollover protective structure (ROPS) or seat belt.

Warning and active steering rollover prevention control for agricultural wheeled tractor.

Tractor rollover is regarded as the most fatal incident in agricultural production, but some of which can be avoided by timely anti-rollover warning and active control. There have been a lot of researches on the tractor rollover model building and rollover protective structure designing but few on the anti-rollover control. The purpose of this study is to develop a cheaper and practical anti-rollover control system based on active steering technique and to prove the efficiency of the proposed scheme for the wheeled tractors. A three-degree-of-freedom rollover dynamics model including automatic steering system is established. A control scheme by adjusting the roll angle to keep the stability based on the adaptive sliding mode control is proposed with the estimated lateral velocity according to the feedback correction principle. Front wheel angle tracking controller is designed adopting internal model control (IMC) theory. Simulation results exhibit that the active anti-rollover control can calculate the stability index in real time and can keep it within the stable range by adjusting the front steering wheel angle. It is prospective for the proposed scheme to provide a valuable reference to reduce tractor rollover accidents.

Design and analysis of electric power-assisted steering in vehicles for mountain forests

This study investigates the problem of vehicle exploitation in the mountainous and wooded regions of the Russian Federation. Considering how critical rollover accidents are in the logging industry, it is vital to ensure safe and stable driving. This study aims to develop a model of electric power steering (EPS) control using a quasi-continuous sliding-mode controller in MATLAB/Simulink. Experiments were carried out under the following conditions: maximum slope angle, 30°; maximum steering angle, 30°; maximum driving speed, 7 m/s. The dynamic characteristics of the suspension and EPS systems were optimized using the receding horizon optimization technique. The theoretical and experimental results suggest that the model reaches its critical state of stability (−0.2) at a speed range of 0–7 m/s with a steering angle of 25°. After optimization, critical stability (0.3) occurs at the driving speed of 7 m/s when the steering angle is 30°. The paper discussed the possibility of installing the EPS control system into vehicles that operate in mountainous wooded areas.

Head Injuries In Rollover of Military Armoured Vehicle

Rollover crashes in vehicles are disproportionately more dangerous and posed a relatively higher risk of severe injuries and fatality rates compared to other configurations such as frontal and side crashes. To date, there is no study being conducted on injury outcomes of rollover accidents involving military armoured vehicles. This study was conducted to examine the driver’s response in rollover of SIBMAS 6X6 and with the aim to evaluate severity of head injury in the incident using finite element simulation. Hybrid III 50th percentile male dummy was incorporated to represent a driver and was thus configured to simulate a typical seated driving posture. Rollover intensity, in terms of initial kinetic energy, which capable of producing two quarter-turns of rolling with vehicle roof landing was imposed via initial angular velocity that applied to the whole vehicle. The dummy’s head was observed to make three significant impacts with hull interior structures from the initiation of rollover and until the roof landed on the ground. Head injury severity was evaluated based on resultant acceleration of head centre of gravity and also 15 ms duration Head Injury Criteria (HIC15). The maximum values of these two criteria were 531g and 9098g, respectively. Evaluation of these severity values with respect to the associated injury risks and also fatality rates as classified in Abbreviated Injury Scale (AIS) clearly indicated that the head injuries sustained by the driver were mostly fatal.

Fasting the stabilization response for prevention of tractor rollover using active steering: Controller parameter optimization and real-vehicle dynamic tests

The rollover problem is prominent for a small tractor under complicated road conditions. The application of active steering (AS) technology is an effective approach to solve this problem. A lateral stability index based on the critical position is proposed and improved. Sliding mode control (SMC) technology based on an exponential terminal sliding mode surface is studied by considering the parameter changes and external disturbances in the rollover process of the tractor, which further accelerates the system’s response speed. A real vehicle test platform was built taking into account the limitations of the few real vehicle dynamic tests in current studies. Real vehicle dynamic tests with varying speeds, slopes, and obstacles were conducted for various road pavements and typical off-road pavements. For road pavements, the results demonstrated that the maximum roll angle of the tractor was 15.94 % less than with that under uncontrolled. For typical off-road pavements, AS control effectively restrained rollover accidents under non-extreme conditions, and SMC reduced the time the tractor was in the critical rollover region by 35.98 % on average compared with PID control. The stability region boundary of a small tractor was defined, and the stable driving region of a tractor on various slopes is obtained. This study provides a specific theoretical basis and implementation plan for guiding the research of tractor active safety technology.