Browse Topic: Rollover accidents

Items (111)
Find
Static Rollover Stability Analysis of Heavy Tipper vehicle2026-26-0090To be published on 01/16/2026
Heavy tipper vehicles are primarily utilized for transporting ores and construction materials. These vehicles often operate in challenging locations, such as mining sites, riverbeds, and stone quarries, where the roads are unpaved and characterized by highly uneven elevations in both the longitudinal and lateral directions of vehicle travel. During the unloading process, the tipper bodies are raised to significant heights, which increases the vehicle's centre of gravity, particularly if the payload material does not discharge quickly. Such conditions can lead to tipper rollover accidents, causing severe damage to life and substantial vehicle breakdowns. To analyse this issue, a study is conducted on the vehicle design parameters affecting the rollover stability of a 35-ton GVW tipper using multi-body simulations in ADAMS software. The tilt table test was simulated to determine the table angle at which wheel lift occurs. Initially, simulations are performed with the rigid body model
Vichare, Chaitanya Ashok, Patil, Sudhir, Gupta, Amit
Integration of virtual testing methods in automotive safety: Methodology validation for rollover protection system (ROPS)2026-26-0375To be published on 01/16/2026
During recent years, the integration of virtual testing methodologies has gained significant importance in vehicle development for the passive safety evaluation. The accuracy of simulation results depends basically on the correct replication of physical test into the virtual model, for example to assign the realistic material properties from the structural components and following the boundary conditions replicated from real conditions. In this study the safety standards ISO 3471_2008 and ANSI ROHVA/OPEI-2016 have been considered as references of the safety validation process of hollow section roll-over protective structure (ROPS) integrated into a vehicle. A key objective is to stablish a virtual test methodology that could be applicable across different standards considering various industry markets, as for example European, American and Asian. A sensitivity analysis is necessary to evaluate what are the main aspects that gives significant deviations in results and in which we can
Laso Rodríguez, Manuel, Hanumantha, Chandrashekhar, Singh, Amit Kumar, Lal, Kundan
REDUCED ORDER MODELLING METHOD (ROMM) FOR GROUND VEHICLE ROLLOVER PROTECTION M&S2024-01-390311/15/2024
ABSTRACT The performance of ground vehicles during a rollover event is an important safety and occupant protection requirement for military vehicles. Modeling and simulation is a very useful tool in study and investigation of vehicle rollover characteristics and countermeasure concepts. This study presents two methods of simulating the rollover events. The first one uses Full System Method (FSM), where all the components are modelled as is and are evaluated. The second method is a reduced order modelling method (ROMM) using integration of the resulted kinematics data from FSM into the vehicle model with occupant & restraints. The FSM & ROMM methods were applied to simulate two HMMMV rollover events, and the results from both methods show that simulation and test data agreed fairly well. Computational time reduced by the ROMM was about 53% of that of the FSM. ROMM approach not only saves significant computational time but also increases robustness of the simulation. Citation: V. Babu, J
Babu, V., Kang, J., Kankanalapalli, S., Sheng, J., Vunnam, M., Karwaczynski, S. K., Jessup, C., Duncan, M., Paulson, K.
Impact of Toe and Thrust Angle Misalignment on Roll Behaviour of a Heavy Commercial Road Vehicle2024-26-005601/16/2024
Heavy Commercial Road Vehicles (HCRVs) may be more susceptible to rollover incidents due to their higher centre of gravity position than passenger vehicles, and rollover is one of the significant causes of HCRV accidents. Therefore, variation in vehicle roll behaviour becomes crucial to the safety of an HCRV. Toe misalignment is a commonly observed phenomenon in HCRVs, and studying its impact on roll behaviour is important. In this work, the impact of the symmetric toe and thrust misalignment on the roll behaviour of an HCRV is analysed using IPG TruckMaker®, a vehicle dynamics simulation software. A ramp steer manoeuvre was used for the simulations, and the toe misalignment on a wheel was chosen from the range [−0.21°, 0.21°]. Variation in roll behaviour was quantified using the steering wheel angle at which one-wheel lift-off (OWL) occurred (SWA_L). Additionally, an analytical model was formulated to predict OWL and the model predictions were compared with the results from IPG
Chandran, Amarchand, Grandhe, Roshan, Mukhopadhyay, Arko, Sharma, Mitanshu, Shankar Ram, C S
Rollover and near-rollover kinematics during evasive steer maneuvers2022-01-104203/29/2022
We present 6-degree-of-freedom (6DOF) kinematic data from two SUVs during evasive steer maneuvers that did and did not result in rollovers. The vehicles were instrumented with a GPS speed sensor, tri-axial accelerometers, tri-axial angular rate sensors, and a steering wheel angle sensor. Drone-based and land-based video cameras recorded all tests. Six degree of freedom position/orientation data were extracted from the video using match moving techniques with 3D constraints from laser scans of the test site and vehicles as described in our previous SAE paper (SAE 2020-01-0272). The initial speeds varied from 100 to 124 km/h and the steering input during the tests were similar. We examine the magnitude and timing of the vehicle pre-roll kinematics to identify differences between the roll and non-roll events. We also present the 6DOF kinematics of the rollovers themselves. This study provides valuable insight into factors that predict roll initiation during evasive steer maneuvers.
Young, Cole, King, David, Siegmund, Gunter
Research on Trajectory Planning and Tracking Strategy of Lane-changing and Overtaking based on PI-MPC Dual Controllers2021-01-126210/11/2021
Aiming at the problem of poor robustness after the combination of lateral kinematics control and lateral dynamics control when an autonomous vehicle decelerates and changes lanes to overtake at a certain distance. This paper proposes a trajectory determination and tracking control method based on a PI-MPC dual algorithm controller. To describe the longitudinal deceleration that satisfies the lateral acceleration limit during a certain distance of lane change, firstly, a fifth-order polynomial and a uniform deceleration motion formula are established to express the lateral and longitudinal displacements, and a model prediction controller (MPC) is used to output the front wheel rotation angle. Through the dynamic formula and the speed proportional-integral (PI) controller to control and adjust the brake pressure. Based on simulation to optimize the best lane change completion time coefficient at different longitudinal lane change speeds, the relationship between the vehicle collision
Yin, Jian, Chen, Xu Jia, Zu, Bingfeng, Xu, Yuliang, Zhou, Jianwei
Articulated Vehicle Lateral Stability Management via Active Rear-Wheel Steering of Tractor Using Fuzzy Logic and Model Predictive Control02-13-02-000807/01/2020
In-phase rear-wheel steering, where rear wheels are steered in the same direction of front wheels, has been widely investigated in the literature for vehicle stability improvements along with stability control systems. Much faster response can be achieved by steering the rear wheels automatically during an obstacle avoidance maneuver without applying the brakes where safe stopping distance is not available. Sudden lane change movements still remain challenging for heavy articulated vehicles, such as tractor and semitrailer combinations, particularly on roads with low coefficient of adhesion. Different lateral accelerations acting on tractor and semi-trailer may cause loss of stability resulting in jackknifing, trailer-swing, rollover, or slip-off. Several attempts have been made in the literature to use active steering of semi-trailer’s rear wheels to prevent jackknifing and rollover. However, loss of stability in an articulated vehicle is usually caused by an oversteered tractor, and
Sahin, Hasan, Akalin, Ozgen
SUV Kinematics during a Steer-Induced Rollover Resolved Using Consumer-Grade Video, Laser Scans and Match-Moving Techniques2020-01-064204/14/2020
Rollover crashes are complex events that generate motions in all six degrees of freedom (6DOF). Directly quantifying the angular rotations from video can be difficult and vehicle orientation as a function of time is often not reported for staged rollover crashes. Our goal was to evaluate the ability of using a match-moving technique and consumer-grade video cameras to quantify the roll, pitch and yaw angles and angular velocities of a rollover crash. We staged a steer-induced rollover of an SUV at 106 km/h. The vehicle was fitted with tri-axial accelerometers and angular rate sensors, and five consumer-grade video cameras (2 on tripods, 2 on drones, 1 handheld, ~30 fps) captured the event. Roll, pitch and yaw angles were determined from the video using specialized software. We then compared the vehicle orientation angles from the video data to the integrated angular rate data measured by onboard sensors, and also compared the angular rates from the differentiated video data to the
Young, Cole R., King, David J., Siegmund, Gunter P.
Evaluation of Laminated Side Glazing and Curtain Airbags for Occupant Containment in Rollover2020-01-097604/14/2020
By their nature as chaotic, high-energy events, rollovers pose a high risk of injury to unrestrained occupants, in particular through exposure to projected perimeter contact and ejection. While seat belts have long been accepted as a highly effective means of retaining and restraining occupants in rollover crashes, it has been suggested that technologies such as laminated safety glazing or rollover-activated side curtain airbags (RSCAs) could alternatively provide effective occupant containment. In this study, a full-scale dolly rollover crash test was performed to assess the occupant containment capability of laminated side glazing and RSCAs in a high-severity rollover event. This allowed for the analysis of unrestrained occupant kinematics during interaction with laminated side glazing and RSCAs and evaluation of failure modes and limitations of laminated glazing and RSCAs as they relate to partial and complete ejection of unrestrained occupants. The dolly rollover was performed with
Miller, Bruce, Smedley, Janine, Carhart, Michael, Sharpe, Sarah, Krishnaswami, Ram
A Novel Prediction Algorithm for Heavy Vehicles System Rollover Risk Based on Failure Probability Analysis and SVM Empirical Model2020-01-070104/14/2020
The study of heavy vehicles rollover prediction, especially in algorithm-based heavy vehicles active safety control for improving road handling, is a challenging task for the heavy vehicle industry. Due to the high fatality rate caused by vehicle rollover, how to precisely and effectively predict the rollover of heavy vehicles became a hot topic in both academia and industry. Because of the strong non-linear characteristics of Human-Vehicle-Road interaction and the uncertainty of modeling, the traditional deterministic method cannot predict the rollover hazard of heavy vehicles accurately. To deal with the above issues, this paper applies a probability method of uncertainty to the design of a dynamic rollover prediction algorithm for heavy vehicles and proposes a novel algorithm for predicting the rollover hazard based on the combined empirical model of reliability index and failure probability. Moreover, the paper establishes a classification model of heavy vehicles based on the
Zhu, Tianjun, Yin, Xiaoxuan, Wang, Zhenfeng, Wang, Dong, Li, Fei, Wang, Xinyu, Ma, Wei, Wang, Zheng
Accident Statistical Distributions from NASS CDS - An Update2020-01-051804/14/2020
The National Automotive Sampling System (NASS) Crashworthiness Data System (CDS) contains an abundance of field crash data. As technology advances and the database continues to grow over the years, the statistical significance of the data increases and trends can be observed. The purpose of this paper is to provide a broad-based, up-to-date, reference resource with respect to commonly sought-after crash statistics. Charts include up-to-date crash distributions by Delta-V and impact direction with corresponding injury severity rates. Rollover data is also analyzed, as well as historical trends for injury severity, belt usage, air bag availability, and the availability of vehicle safety technology.
Yaek, Jennifer L., Brown, Thomas, Goertz, Alan
Update on Second-Row Children Responses in Rear and Frontal Crashes with a Focus on the Potential Effect of Stiffening Front Seat Structures2020-01-121504/14/2020
NHTSA has recently been petitioned to address the protection of second-row children in rear crashes due front seatback performance. The protection of children is important. However, it is more complex than assessing front seat performance in rear impacts. Viano, Parenteau (2008 [1]) analyzed cases of serious-to-fatally injured (MAIS 3+F) children up to 7 years old in the second row in rear impacts involving 1990+ model year vehicles using 1997-2005 NASS-CDS. They observed that intrusion was an important factor pushing the child forward into the back of the front seat, B-pillar or other front structure. To help assess whether stiffening the front seats would be beneficial for second-row child safety, the 2008 study was updated using more recent data and model year vehicles. In the present study, 1997-2015 NASS-CDS data were analyzed for serious-to-fatally (MAIS 3+F) injured 0- to 7-year old children in the second row with 1994+ model year vehicles. First, the data were analyzed to
Parenteau, Chantal, Viano, David
The Effect of Obesity on Rollover Ejection and Injury Risks2020-01-121904/14/2020
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. Complete ejection was highest for unbelted occupants, irrespective of BMI, and uncommon for belted occupants
Parenteau, Chantal, Smedley, Janine, Carhart, Michael, Dibb, Alan
Accuracy and Sensitivity of Yaw Speed Analysis to Available Data2019-01-041704/02/2019
Accident reconstructionists rarely have complete data with which to determine vehicle speed, and so the true value must be bracketed within a range. Previous work has shown the effect of friction uncertainty in determining speed from tire marks left by a vehicle in yaw. The goal of the current study was to assess improvements in the accuracy of vehicle speed estimated from yaw marks using progressively more scene and vehicle information. Data for this analysis came from staged S-turn maneuvers that in some cases led to rollover of sport utility vehicles. Initial speeds were first calculated using the critical curve speed (CCS) formula on the yaw marks from the first portion of the S-maneuver. Then computer simulations were performed with progressively more input data: i) the complete tire marks from the whole S-maneuver, ii) measured vehicle mass, iii) measured suspension stiffness and damping, and iv) measured steering history. Simulations based on the complete tire marks reduced the
Heinrichs, Bradley, Lee, Janice, Young, Cole
An Analytical Review and Extension of Two Decades of Research Related to PC-Crash Simulation Software2018-01-052304/03/2018
PC-Crash is a vehicular accident simulation software that is widely used by the accident reconstruction community. The goal of this article is to review the prior literature that has addressed the capabilities of PC-Crash and its accuracy and reliability for various applications (planar collisions, rollovers, and human motion). In addition, this article aims to add additional analysis of the capabilities of PC-Crash for simulating planar collisions and rollovers. Simulation analysis of five planar collisions originally reported and analyzed by Bailey [2000] are reexamined. For all five of these collisions, simulations were obtained with the actual impact speeds that exhibited excellent visual agreement with the physical evidence. These simulations demonstrate that, for each case, the PC-Crash software had the ability to generate a simulation that matched the actual impact speeds and the known physical evidence. Simulation of a full-scale rollover test reported by Asay [2010] is also
Rose, Nathan A., Carter, Neal
The Causal Relationship between Wheel Rim Gouging Forces on Roadway Surfaces and Rollover Crashes2018-01-055604/03/2018
There has been a general consensus in the scientific literature that a rim gouging, not scraping, into a roadway surface generates very high forces which can cause a vehicle to overturn in some situations. However, a paper published in 2004 attempts to minimize the forces created during wheel rim gouging and the effect on vehicle rollover. This paper relied largely on heavily filtered lateral acceleration data and discounted additional test runs by the authors and NHTSA that did not support the supposed conclusions. This paper will discuss the effect of rim gouging using accepted scientific methods, including full vehicle testing where vehicle accelerations were measured during actual rim gouging events and static testing of side forces exerted by wheels mounted on a moving test fixture. The data analyzed in this paper clearly shows that forces created by rim gouges on pavement can be thousands of Newtons and can contribute to vehicle rollover.
Tandy, Donald F., Pascarella, Robert, Coleman, Clay, Colborn, Jason
Study on the Handling Stability for an Articulated Truck with Four Motor-Driven Wheels2017-01-183306/05/2017
Articulated engineering vehicle travels on complex road, its working condition is bad and because of the non-rigid connection between the front and rear body, additional DOF is brought in and the transverse stiffness is relatively weak. When the articulated vehicle runs in a high speed along a straight line, it is easy to cause the transverse swing and the poor handling stability. If it is serious enough, it will lead to "snakelike" instability phenomenon. This kind of instability will increase driving resistance and tire wear, the lateral dynamic load and aggravate the damage of the parts. The vehicle will have a lateral migration of center of gravity (CG) when steering, which will lead a higher probability of rollover accident. A dynamic mathematical model for a 35t articulated truck with four motor-driven wheels was established in this paper, to study the condition for its stable driving and the influence of the vehicle structural parameters. This part research focused on the
Qin, Bonan, Yang, Jue, Zhao, Xinxin
Active Hydraulically Interconnected Suspension. Modeling and Simulation2017-01-156103/28/2017
Rollover prevention is one of the prominent priorities in vehicle safety and handling control. A promising alternative for roll angle cancellation is the active hydraulically interconnected suspension. This paper represents the analytical model of a closed circuit active hydraulically interconnected suspension system followed by the simulation. Passive hydraulically interconnected suspension systems have been widely discussed and studied up to now. This work specifically focuses on the active hydraulically interconnected suspension system. Equations of motion of the system are formalized first. The system consists of two separate subsystems that can be modeled independently and further combined for simulation. One of the two subsystems is 4 degrees of freedom half-car model which simulates vehicle lateral dynamics and vehicle roll angle response to lateral acceleration in particular. The other subsystem is active hydraulically interconnected suspension system which is responsible for
Tkachev, Anton A., Zhang, Nong
Investigation of Rollover Prevention with Coupling from Driver Yaw Control Using a Scaled Vehicle2017-01-157903/28/2017
The development of an integrated controller for a 4WS/4WD electric bus is investigated. The front wheel steering angle is assumed to be controlled by the human driver. The vehicle is controlled by the rear wheel steering and the yaw moment that can be generated by the differential torque/brake control on each wheel. The high speed cornering is used as the testing scenario to validate the designed controller. Due to the highly nonlinear and the multiple-input and multiple-output nature, the control design is separated into different stages using the hierarchical layer control concept. The longitudinal speed is controlled using a PI controller together with a rule-based speed modification. The other two control inputs, namely the rear wheel steering and the DYC moment, are then designed using the state-dependent Riccati equation method. The designed controllers are evaluated using computer simulations first, and the simulations showed promising results. A scaled electric bus is being
Chen, Liang-kuang, Chen, Chien-An
Development of a Biofidelic Rollover Dummy-Part II: Validation of the Kinematic Response of THOR Multi-Body and Finite Element Models Relative to Response of the Physical THOR Dummy under Laboratory Rollover Conditions2016-01-148604/05/2016
While over 30% of US occupant fatalities occur in rollover crashes, no dummy has been developed for such a condition. Currently, an efficient, cost-effective methodology is being implemented to develop a biofidelic rollover dummy. Instead of designing a rollover dummy from scratch, this methodology identifies a baseline dummy and modifies it to improve its response in a rollover crash. Using computational models of the baseline dummy, including both multibody (MB) and finite element (FE) models, the dummy’s structure is continually modified until its response is aligned (using BioRank/CORA metric) with biofidelity targets. A previous study (Part I) identified the THOR dummy as a suitable baseline dummy by comparing the kinematic responses of six existing dummies with PMHS response corridors through laboratory rollover testing. In this study (Part II), the whole-body kinematic responses of the THOR MB and FE models were validated with responses of the physical THOR dummy in experiments
Zhang, Qi, Gepner, Bronislaw, Toczyski, Jacek, Kerrigan, Jason
An Analysis of Recreational Off Road Vehicle Tire Performance Characteristics2016-01-163504/05/2016
Recreational Off Road Vehicles (ROVs) which are sometimes referred to as side-by-sides, have increased in popularity over the last decade. These vehicles are available in many different sizes and performance characteristics from a host of different manufacturers and also have a variety of different missions, just as there are many types of off road terrain. The United States Federal Government, through the Consumer Product Safety Commission (CPSC), has advocated and proposed vehicle handling and rollover resistance standards for the side-by-sides which have a top speed above 25 miles per hour (these are not defined as “low speed vehicles”). For the sake of repeatability, the proposed maneuvers are to be performed on a high friction hard surface (like asphalt) as opposed to the off road surfaces (i.e. grass, sand, dirt, mud. rocks, etc.) that these vehicles are designed to be operated on. Since ROV tires are designed for off road use only, their force and moment characteristics on an
Tandy, Donald F., Bae, Jung, Colborn, Jason, Coleman, Clay
Responses of the Q6/Q6s ATD Positioned in Booster Seats in the Far-Side Seat Location of Side Impact Passenger Car and Sled Tests2015-22-001211/09/2015
Passenger car side impact crash tests and sled tests were conducted to investigate the influence of booster seats, near-side occupant characteristics and vehicle interiors on the responses of the Q6/Q6s child ATD positioned in the rear, far-side seating location. Data from nine side impact sled tests simulating a EuroNCAP AEMD barrier test were analyzed with data obtained from 44 side impact crash tests. The crash tests included: FMVSS 214 and IIHS MDB, moving car-to-stationary car and moving car-to-moving car. A Q6 or prototype Q6s ATD was seated on the far-side, using a variety of low and high back booster seats. Head and chest responses were recorded and ATD motions were tracked with high-speed videos. The vehicle lateral accelerations resulting from MDB tests were characterized by a much earlier and more rapid rise to peak than in tests where the bullet was another car. The near-side seating position was occupied by a Hybrid III 10-year-old ATD in the sled tests, and a rear or
Tylko, Suzanne, Bohman, Katarina, Bussières, Alain
Handling-Stability Oriented Parameter Optimization for a Tractor Semi-Trailer Vehicle2015-01-275309/29/2015
Tractor semi-trailer as a widely-used heavy duty freight vehicle has caused many fatal accidents every year and one of the main factors of which may relate to its relatively poor lateral dynamics performance compared to the passenger cars [1, 2, 3]. In this paper, attention is concentrated on the parametric design for a tractor semi-trailer by optimizing the configuration parameters aiming to comprehensively improve the lateral dynamics performance. According to the previous public reports, the performance measures such as Load Transfer Ratio (LTR), Static Rollover Threshold (SRT), Rearward Amplification Ratio (RAR) and Ratio of Yaw Rate (RYR) are very effective measures and often be used to evaluate the handling and stability performances for tractor-trailer vehicles. However, each of those measures only pays attention to a certain aspect of vehicle lateral dynamics which is closely related to vehicle configuration parameters. Especially, the load scenario in transport which often
Yang, Xiujian, Zhu, Ruocheng, Gao, Jin
Vertical Occupant Loading in Car Crashes; Test Methods and Countermeasures2015-01-145904/14/2015
Vertical loading can cause thoracic and lumbar spine injuries to a car occupant. Crashes potentially causing occupant vertical loads include; rollover events or free flying events when the car lands on its wheels, and run off road events when the car goes into the ditch and collides with an embankment. To date, there is no standardized test method evaluating this occupant loading mechanism. The aim of this study was to develop test methods addressing vertical occupant loading for car occupants and to evaluate countermeasures for reduction of such loads. Based on real world run off road crashes, representative test track methods were developed. These complete vehicle test track methods were used to provide input to a simplified and repeatable rig test method. The rig test method comprises a dummy positioned in a seat attached to a frame and exposed to a vertical acceleration. Vertical pelvis acceleration is monitored, as an indication of potential loads through the spine. Two different
Jakobsson, Lotta, Björklund, Magnus, Axelson, Anders
Implementation and Experimental Study of a Novel Air Spring Combined with Hydraulically Interconnected Suspension to Enhance Roll Stiffness on Buses2015-01-065204/14/2015
Air spring due to its superior ride comfort performance has been widely used in distance passenger transporting vehicles. Since the requirements for ride comfort and handling performance are contradict to each other, handling performance and even roll stability are sacrificed to some extent to obtain good ride comfort. Due to the complex terrain and limited manufacturing level, in the past several years, bus rollover accidents with serious casualties have been reported frequently and bus safety has attracted more and more attention from bus manufacturers in China. On one hand the bus standards have to be raised, and on the other hand, novel solutions which can effectively improve the roll stability of air spring bus are needed to replace the inadequacy of anti-roll bars. This paper starts from experiment-based system parameter estimation to identify the handling issues of the new bus and redefine the design scope, then a combination design of air spring with an anti-roll hydraulically
Hua, Hui, Wang, Lifu, Qi, Hengmin, Zhang, Jie, Zhang, Nong
Analyzing Rollover Indices for Critical Truck Maneuvers2015-01-159504/14/2015
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 analysis is based on optimal control applied to a five degrees of freedom chassis model with individual wheel dynamics and high-fidelity tire-force
Lundahl, Kristoffer, Lee, Chih Feng, Frisk, Erik, Nielsen, Lars
On the Directionality of Rollover Damage and Abrasions2015-01-142104/14/2015
Vehicle rollovers generate complicated damage patterns as a result of multiple vehicle-to-ground contacts. The goal of this work was to isolate and characterize specific directional features in coarse- and fine-scale scratch damage generated during a rollover crash. Four rollover tests were completed using stock 2001 Chevrolet Trackers. Vehicles were decelerated and launched from a rollover test device to initiate driver's side leading rolls onto concrete and dirt surfaces. Gross vehicle damage and both macroscopic and microscopic features of the scratch damage were documented using standard and macro lenses, a stereomicroscope, and a scanning electron microscope (SEM). The most evident indicators of scratch direction, and thus roll direction, were accumulations of abraded material found at the termination points of scratch-damaged areas. Abrasive wear mechanisms caused local plastic deformation patterns that were evident on painted sheet metal surfaces as well as plastic trim pieces
Turriff, Dennis, King, David J., Bertoch, James
Glass Debris Field Longevity for Rollover Accident Reconstruction2015-01-142704/14/2015
Vehicles involved in rollover crashes can leave debris trails which can include glass from broken windows. The glass patterns can be useful to identify the vehicles path during the rollover and the location and orientation of the vehicle at various vehicle-to-ground impacts. The location of glass, which is often window specific, can be used to identify where the window fractured during the rollover sequence. The longevity of the glass debris fields, subject to various real-world conditions and disturbances (i.e. slope, weather, mowing, soil type, etc.), was tested over a period of two years. The glass debris fields were placed and mapped in multiple locations across the United States. Periodically during each year, the glass debris fields were examined and the new field extents were mapped. The comparison between the original debris field and the subsequent debris fields are presented. At the completion of the research, the glass debris fields were collected and compared to what was
Przybyla, Jay, Jupe, Jason, Rush, Thomas, Keller, Rachel
A Comparison of Bayesian Speed Estimates from Rollover and Critical Speed Methods2015-01-143404/14/2015
Martinez and Schlueter [6] described a three-phase model for reconstructing tripped rollover crashes, where the vehicle's path is divided into pre-trip, trip, and post-trip phases. Brach and Brach [9] also described this model and noted that the trajectory segmentation method for the pre-trip phase needed further validation. When a vehicle leaves a measurable yaw mark at the start of its pre-trip phase it might be possible to compare estimates from the three-phase model to those obtained using the critical speed method, and this paper describes Bayesian reconstruction of two such cases. For the first, the 95 percent confidence interval for the case vehicle's initial speed, estimated using the critical speed method, was (64 mph, 81 mph) while the 95 percent confidence interval via the three-phase model was (66 mph, 79 mph). For the second case an initial inconsistency between the two estimates suggested a modification to the three-phase model, leading to confidence intervals of (72 mph
Davis, Gary A.
The Influence of Body Mounted Shoulder Seat Belt Anchor (D-Ring) Displacement During Dynamic Vehicle-to-Ground Impacts2015-01-175604/14/2015
For more than 30 years, field research and laboratory testing have consistently demonstrated that properly wearing a seat belt dramatically reduces the risk of occupant death or serious injury in motor vehicle crashes. In severe rollover crashes, deformation to vehicle body structures can relocate body-mounted seat belt anchors altering seat belt geometry. In particular, roof pillar mounted shoulder belt anchors (“D-rings”) are subject to vertical and lateral deformation in the vehicle coordinate system. The ROllover Component test System (ROCS) test device was utilized to evaluate seat belt system performance in simulated severe rollover roof-to-ground impacts. A mechanical actuator was designed to dynamically relocate the D-ring assembly during a roof-to-ground impact event in an otherwise rigid test vehicle fixture. Anthropomorphic test device (ATD) kinematics and kinetics and seat belt tensions were compared between tests with and without D-ring relocation. Results indicate that
Toomey, Daniel E., Marth, Debora R., Ballard, William G., Belwafa, Jamel E., Burnett, Roger, McCoy, Robert W.
Effects of Liquid Cargo on Lateral Stability of B-Train Combination2014-01-231909/30/2014
Road train vehicles have been applied as one of the common and efficient ways for transportation of goods, specifically hazardous liquid cargos, in different nations. These vehicles have a wide variety of lengths and towing systems such as the fifth wheel or the dolly draw-bar. Based upon specific regulations, they could be authorized to move on specific roads. In order to avoid hazard and danger in case of accidents, safety performance of a B-train vehicle as a specific type of road train vehicles is investigated in this paper. A Multi-Body Dynamic (MBD) model, which consists of a prime mover and two trailers coupled by fifth wheels, are simulated in the initial phase of the study. The developed dynamic model is capable of simulating required tests as well as the SAE lane change, along with a constant radius turn for the purpose of roll and yaw stability analysis and safety evaluation. The effects of variation of the fluid fill level are considered in this research. The trammel
Hazrati Ashtiani, Iman, Abedi, Mehrnoosh
Simulations of Heavy Truck Rollovers and Sleeper Restraint System Effectiveness2014-01-242009/30/2014
Federal Motor Carrier Safety Requirement (FMCSR) 393.76(h) states that “a motor vehicle manufactured on or after July 1, 1971 and equipped with a sleeper berth must be equipped with a means of preventing ejection of the occupant of the sleeper berth during deceleration of the vehicle.” [1] Furthermore, this standard requires that “the restraint system must be designed, installed and maintained to withstand a minimum total force of 6,000 pounds applied toward the front of the vehicle and parallel to the longitudinal axis of the vehicle.” [1] Today, sleeper berths are equipped with sleeper restraint systems that function to contain the sleeper occupant inside the sleeper berth during reasonably foreseeable crashes. To assess the effectiveness of sleeper restraint systems, computer simulation models of the sleeper cab environment and these restraint systems were developed, with a simulated supine occupant in the sleeper. The model was evaluated using two different rollover crash scenarios
Chinni, James, Butler, Robert, Yang, Shu
Implementation of Real-Time Vehicle Rollover Prevention System2014-01-014904/01/2014
Vehicle Rollover Prevention/Warning Systems have recently been an important topic in Advanced Driver Assistance Systems (ADAS) of automotive electronics field. This paper will propose a rollover-prevention system implementation with vehicle dynamic model, video-detection technique and rollover index to help the driver avoid accidents as driving into a curve. Due to the reason that vehicle rollover motion analysis needs complicated computation and accurate parameters of vehicle stability in real time, in the first stage a vehicle dynamic model based on Extended Kalman Filter (EKF) algorithm is built, which can estimate vehicle roll/yaw motion in the curve by vehicle sensors. And then the image-based technique will be employed in detecting the front road curvature, and combined in the system to predict vehicle steering status. The final stage is to apply the vehicle rollover index with estimated vehicle motion to predict the dangerous level to drivers for warning. In the system
Yao, Chi-Chun, Hsu, Jin-Yan, Liao, Yu-Sheng, Li, Ming Hung
Improving Stability of a Narrow Track Personal Vehicle using an Active Tilting System2014-01-008704/01/2014
A compact sized vehicle that has a narrow track could solve problems caused by vehicle congestion and limited parking spaces in a mega city. Having a smaller footprint reduces the vehicle's total weight which would decrease overall vehicle power consumption. Also a smaller and narrower vehicle could travel easily through tight and congested roads that would speed up the traffic flow and hence decrease the overall traffic volume in urban areas. As an additional benefit of having a narrow track length, a driver can experience similar motorcycle riding experience without worrying about bad weather conditions since a driver sits in a weather protected cabin. However, reducing the vehicle's track causes instability in vehicle dynamics, which leads to higher possibility of rollovers if the vehicle is not controlled properly. A three wheel personal vehicle with an active tilting system is designed in MapleSim. The vehicle is driven by constant rotational input which is applied to the rear
Kim, Shinhoon, McPhee, John, Lashgarian Azad, Nasser
High Speed Optimal Yaw Stability of Tractor-Semitrailers with Active Trailer Steering2014-01-009304/01/2014
Most tractor-semitrailers are fitted with multi-axle trailers which cannot be actively steered, and such vehicles with an articulated configuration are inclined to exhibit instability such as trailer swing, jack-knifing, and rollover at high speed. Proposed in this paper is an optimal control of the yaw stability of tractor-semitrailers at high speed by applying an active trailer's steering angle. An optimal control algorithm is designed by employing a 3-DOF vehicle model in the yaw plane. The optimal linear quadratic regulator (LQR) approach is used with a cost function including sideslip angles, yaw rates of both tractor and trailer, and trailer's steering angle. The yaw stability at the high speed is also quantified by the dynamic performance measurements of lateral path deviation, hitch angle and rearward amplification (RA). The algorithm is evaluated by co-simulations using TruckSim and Matlab/Simulink softwares. Simulation results under double lane change maneuvers show that
Lin, Xiaomin, Ding, Nenggen, Xu, Guoyan, Gao, Feng
Performance Analysis of Active Independent Front Steering (AIFS) for Commercial Vehicles with Greater Lateral Load Shift Propensity2013-01-235509/24/2013
An Active Independent Front Steering (AIFS) offers attractive potential for realizing improved directional control performance compared to the conventional Active Front Steering (AFS) system, particularly under more severe steering maneuvers. The AIFS control strategy adjusts the wheel steer angles in an independent manner so as to utilize the maximum available adhesion at each wheel/road contact and thereby compensate for cornering loss caused by the lateral load transfer. In this study, the performance potentials of AIFS are explored for vehicles experiencing greater lateral load transfers during steering maneuvers such as partly-filled tank trucks. A nonlinear yaw plane model of a two-axle truck with limited roll degree-of-freedom is developed to study the performance potentials of AIFS under different cargo fill conditions. The lateral movement of the cargo within a partly-filled cylindrical tank is described by the resulting lateral load shift, lateral force and the roll moment
Farazandeh, Azadeh, Ahmed, A. K. W., Rakheja, S.
Effect of Terrain Roughness on the Roll and Yaw Directional Stability of an Articulated Frame Steer Vehicle2013-01-236609/24/2013
Compared to the vehicles with conventional steering, the articulated frame steer vehicles (ASV) are known to exhibit lower directional and roll stability limits. Furthermore, the tire interactions with relatively rough terrains could adversely affect the directional and roll stability limits of an ASV due to terrain-induced variations in the vertical and lateral tire forces. It may thus be desirable to assess the dynamic safety of ASVs in terms of their directional control and stability limits while operating on different terrains. The effects of terrain roughness on the directional stability limits of an ASV are investigated through simulations of a comprehensive three-dimensional model of the vehicle with and without a rear axle suspension. The model incorporates a torsio-elastic rear axle suspension, a kineto-dynamic model of the frame steering struts and equivalent random profiles of different undeformable terrains together with coherence between the two tracks profiles. The
Pazooki, Alireza, Rakheja, Subhash, Cao, Dongpu
A Methodology to Assess Road Tankers Rollover Trend During Turning2013-01-068204/08/2013
An experimental methodology is proposed to measure the rollover propensity of road tankers when subjected to lateral perturbations derived from steering manoeuvers. The testing principle involves subjecting a scaled down sprung tank to the elimination of a lateral acceleration, to analyze its rollover propensity as a function of various vehicle's operational and design parameters. Initial acceleration is generated through putting the scaled tank on a tilt table supported by a hydraulic piston. The controlled release of the fluid in the hydraulic system generates a perturbation situation for the tank, similar to the one that a vehicle experiences when leaving a curved section of the road and going to a straight segment. Durations for the maneuver and initial tilt angles characterize both the corresponding intensities of the steering maneuver. The use of this methodology to analyze the effect of fill level, initial acceleration and tank shape on the rollover propensity of a sprung tank
Romero, Jose Antonio, Betanzo-Quezada, Eduardo, Lozano-Guzman, Alejandro
Design for Vehicle Rollover Warning System2013-01-067504/08/2013
Rollover accidents are a serious and too frequent incident at many locations on the road. Especially in the condition of trucks or Sport Utility Vehicles (SUV) travelling at high speeds require a greatly reduced speed when meeting the exit ramps and tight curves. The usual cause of rollovers is driving behavior, typically excessive speed while cornering which adversely affects the stability of the vehicle. Sudden or severe changes in direction can create a potential risk to rollover. By the time drivers see or feel something wrong, it is usually too late to prevent a rollover. Although some papers discuss many methods to eliminate the rollover phenomenon, it could not provide early warning for the driver. These systems usually work in the condition of slipping or near rollover. To overcome the problem, an alternate approach is to incorporate an image-based detection technique with rollover prediction model. This paper estimates the maximum rollover threshold speed in real time by using
Chen, Chun Hsiung, Yao, Chi-Chun, Liao, Yu-Sheng
The Front Center Airbag2013-01-115604/08/2013
General Motors and the Takata Corporation have worked together to bring to production a new, industry first technology called the Front Center Airbag which is being implemented on General Motors' 2013 Midsize Crossover Vehicles. This paper reviews field data, describes the hardware, and presents occupant test data to demonstrate in-position performance in far side impacts. The Front Center Airbag is an airbag that mounts to the inboard side of the driver front seat. It has a tubular cushion structure, and it deploys between the front seating positions in far side impacts, near side impacts and rollovers, with the cushion positioning itself adjacent the driver occupant's head and torso. This paper includes pictures of the technology along with a basic description of the design. In-position occupant performance is also described and illustrated with several examples. Single occupant and two front occupant far side impact test data are included, both with and without the airbag present
Thomas, Scott D., Wiik, Richard A., Brown, Jacqueline E.
A Multi-Objective LMI-Based Antiroll Control System2012-01-190409/24/2012
A long standing problem with heavy vehicle stability has been rollover. With the higher center of gravity, heavier loads, and narrower tracks (as compared to passenger vehicles), they have a lower rollover stability threshold. In this paper, a rollover stability control algorithm based on a two-degrees-of-freedom (DOF) and a three-DOF vehicle model for a two-axle truck was developed. First, the 3DOF model was used to predict the future Lateral load Transfer Rate (LTR). Using this LTR value, the dynamic rollover propensity was estimated. Then, a robust output feedback gain control rollover stability control algorithm based on the combination of active yaw control and active front steering control was developed. A H₂/H∞/poles placement multi-objective control strategy was developed based on the 2DOF reference model. After the control objectives were determined, the Linear Matrix Inequality (LMI) technique was utilized to solve the restrictions and to carry out the output feedback gain
Zhao, Jian, Taheri, Saied
Comparison of Linear Variable Deceleration Rate Rollover Reconstruction to Steer-Induced Rollover Tests2012-01-046904/16/2012
A variable deceleration rate approach to rollover crash reconstruction was proposed in 2009 by Rose and Beauchamp. A detailed description of Rose and Beauchamp's method was outlined in 2010. The method used a Linearly Variable Deceleration Rate (LVDR) as a function of roll distance. Improvements in responses as a function of time was demonstrated by Rose and Beauchamp using test data from two 208 dolly rollover tests; however, they noted that additional validation work using steering-induced rollover tests would be desirable. This paper provides additional validation of the LVDR model using the steer-induced rollover test data reported in 2011 by Stevens et al. The Over-The-Ground Speed (OGS) and recorded roll rate results from the five steer-induced rollover tests reported by Stevens' in 2011 were compared to reconstructed speed and roll rates as a function of time using the 2010 Rose and Beauchamp LVDR method. Using an appropriate range of average drag factors, the LVDR method
Arndt, Mark W., Stevens, Don, Arndt, Stephen
Seat Belt Restraint Evidence Generated in the Presence of Fractured Glass2012-01-008404/16/2012
Physical evidence on the seat belt restraint system is one source of data used by investigators to determine whether or not an occupant was wearing their seat belt during a crash. Evidence of occupant loading on seat belts generated during crash events has been thoroughly researched and is well documented in the literature. However, there is a paucity of data regarding the physical evidence produced when fractured glass is introduced into the restraint system during occupant loading events. The objective of this study is to characterize the physical evidence generated by glass-to-seat belt interaction during low-level impact loading, and compare this evidence with the types of seat belt marks that can be generated inadvertently by accident scene bystanders, emergency responders, and crash investigators. The presence of glass particles in and around the vehicle at the end of a crash event may contribute to the inadvertent generation of physical evidence. Movable side windows composed of
Moralde, Marie, Dibb, Alan, Smedley, Janine, Carhart, Michael, Cooper, Eddie
An Integrated Model of Rolling and Sliding in Rollover Crashes2012-01-060504/16/2012
Rollover crashes are often difficult to reconstruct in detail because of their chaotic nature. Historically, vehicle speeds in rollover crashes have been calculated using a simple slide-to-stop formula with empirically derived drag factors. Roll rates are typically calculated in an average sense over the entire rollover or a segment of it in which vehicle roll angles are known at various positions. A unified model to describe the translational and rotational vehicle dynamics throughout the rollover sequence is lacking. We propose a pseudo-cylindrical model of a rolling vehicle in which the rotational and translational dynamics are coupled to each other based on the average frictional forces developed during ground contacts. We describe the model as pseudo-cylindrical because vertical motion is ignored but the ground reaction force is not constrained to act directly underneath the center of gravity of the vehicle. The tumbling phase of a rollover is modeled in three distinct phases: an
Funk, James, Wirth, Jeffrey, Bonugli, Enrique, Watson, Richard, Asay, Alan
Influence of Complying with FMVSS 226 (Ejection Mitigation) on Side Airbag Occupant Out of Position Injury Assessment2012-01-046604/16/2012
The National Highway Traffic Safety Administration (NHTSA) has identified ejection mitigation as a top priority, issuing a final rule for FMVSS 226, Ejection Mitigation, in January of 2011 to set performance standards for a vehicle's ejection mitigation countermeasures to mitigate the risk of ejection through a vehicle's side window openings. The most likely countermeasures to be used for compliance with this standard are rollover activated curtain airbags that deploy from a vehicle's roof rail. However, this rule will most likely result in increases in the coverage area and inflator outputs of the curtain airbag; which may influence out-of-position occupant injury as measured in the test methods that have been outlined by the Side Airbag Out-of-Position Injury Technical Working Group (TWG). This paper presents a case study in which the out-of-position performance of a curtain airbag optimized for both ejection mitigation and side impact protection, as outlined per FMVSS 226 and FMVSS
Dix, Jeff, Hammoud, Selim, Cardinali, Alex, Mitchell, Abe, Fulk, Daniel
A Study of the Ditch Fall-over Test Method Using Numerical Simulation2012-01-009404/16/2012
Rollover tests are performed to design the algorithms for deployment of countermeasures to mitigate occupant ejection in rollover situations. The ditch fall-over test is one of the rollover test methods in which a vehicle on a steep slope, representing a ditch embankment, is subjected to a forced steering operation that results in a turnover. An accurate prediction method is needed to determine the specifications of the ditch fall-over test equipment and test conditions because a test-based trial-and-error process involves high cost of performing repeated experiments and preperation for various types of related test equipment. This paper presents a newly developed numerical simulation method for simulating vehicle behavior in ditch fall-over tests. The vehicle model used in the simulation incorporates a finite element tire model for calculating the contact forces to a steep slope in a rollover situation characterized by large contact patch deformation with very large camber angles
Fukushima, Tatsuya, Shitamichi, Masafumi, Nishikata, Osamu, Mori, Masamitsu, Hatano, Keiji, Torigaki, Toshikazu, Nishi, Masato, Miyachi, Takahiko
Rollovers and Neck Injuries10VARANN2803/07/2012
In roughly the last decade there has been an explosion of research related to rollovers. A search of the SAE Safety Series alone demonstrates fewer than a half-dozen articles per year from 1979 until 1997, with an average of roughly 1 to 2 articles per year. From 1998 to present there have between 8 and 20 articles per year with an average of 12 articles per year. It should come as no surprise that much of the research was spurred on by Notices of Proposed Rulemaking regarding rollovers published by the NHTSA in the mid-90?s. Regardless of how one feels about the eventual outcomes of the NHTSA?s rulemaking process, as a community of researchers we can all attest to the fact that our understanding of rollovers has grown by leaps and bounds in the last decade. In this address I hope to synthesize, in a meaningful way, the history of rollover research, its present state, and what I believe the future holds. The focus of this address will necessarily center on accident reconstruction and
Carter, Jarrod
Review and Comparison of Published Rollover Test Results10VARANN2712/12/2011
Rollover research data is a valuable resource in the field of accident reconstruction and automotive safety. This data can provide the accident reconstructionist with information regarding number of rolls versus roll distance and vehicle average deceleration during the rollover event. One source of rollover research data readily available to the general public is the National Highway Traffic Safety Administration's (NHTSA) Crash Test Database which includes dolly rollover test data. This data includes testing performed using the FMVSS 208 dolly fixture and the NHTSA Rollover Test Device (RTD) used from 1985 to 1995. The purpose of this paper is to provide a more thorough analysis of the RTD rollover tests performed for NHTSA which includes a history of the RTD test series, detailed review and analysis of the available data and videos to provide a better understanding of the actual vehicle test dynamics. The analyzed RTD test results are then compared regarding number of rolls, roll
L., Jennifer
Effects of Safety Belt Pretensioning on ATD Motion in Rigid Fixture Rollover Testing2011-01-111804/12/2011
General Motors conducted a series of subsystem rigid fixture sled rollover tests to evaluate the effects of various safety belt pyrotechnic pretensioners on Anthropomorphic Test Device (ATD) head motion. Twelve tests were conducted using a rigid fixture comprised of a modified compact sport utility vehicle (SUV) body encased in a rigid exoskeleton. The testing simulated the pre-trip/trip, free flight and first roof to ground impact phases of a field representative curb trip initiation rollover crash test with a roof to ground impact angle of approximately 180 degrees. Various combinations of safety belt lap anchor, buckle and retractor pretensioners were tested and film analysis was used to measure trailing side ATD head motion relative to the vehicle. Additionally, a new analysis technique of measuring the reduction of lap webbing length during the crash event was developed for evaluating the ability of a restraint system to reduce ATD head motion during the rollover tests. The
White, James, Sevigny, Jennifer, Antonucci, Antonio, Haldenwanger, Michael, O'Brien-Mitchell, Bridget M., Cassatta, Stephen Joseph, Wendzinski, Michael, Cooper, Gerald
A Study of Occupant Ejection Mitigation in Side Impact Crashes2011-01-010604/12/2011
The National Highway Traffic Safety Administration (NHTSA) has identified ejection mitigation as a top priority, issuing a notice of proposed ruling making (NPRM) in December of 2009. The NPRM proposes a linear impact test that uses a featureless head-form to impact a vehicle's side windows' daylight opening at various positions. The test measures the excursion of the head-form beyond the plane of the window glazing. The intention is to evaluate the ability of a vehicle's ejection mitigation system, such as the curtain airbag or other vehicle features, to manage the impactor energy and limit excursion. The NPRM proposes a test conducted 1.5 seconds after the ejection mitigation countermeasure is deployed at an impact speed of 24 km/h with a mass of 18 kg (400 Joules). This test condition is intended to consider both rollover and side impact crashes. While the majority of the research published to date has concentrated on occupant ejections in rollover crashes, there is little published
Dix, Jeff, Sagawa, Koichi, Sahare, Lalitkumar, Hammoud, Selim, Fulk, Daniel, Cardinali, Alex
Items per page:
1 – 50 of 111