Underrun Protective Device Research Articles

Crashworthiness Performance of Rear Underrun Protection Device under Simulated Car Collision

<div>A rear underrun protection device (RUPD) plays a fundamental role in reducing the risk of running a small car beneath the rear or the side of a heavy truck because of the difference in structure heights in the event of a vehicle collision. Even in cars with five-star safety ratings, crashing into a truck with poorly designed RUPD results in a passenger compartment intrusion (PCI) more than the maximum allowable limit as per the United States (US) American National Highway Traffic Safety Administration (NHTSA) standards Federal Motor Vehicle Safety Standard (FMVSS). In this article, mild steel was used to fabricate the new designs of RUPD. The design was analyzed using finite element (FE) analysis LS-DYNA software. Simulations of a Toyota Yaris 2010 and Ford Taurus 2001 were performed at a constant speed of 63 km/h at the time of impact. The ability to prevent severe injuries in a collision with the rear side of the truck was estimated to optimize the underrun design. The new design has achieved the goal of decreasing the head acceleration beyond the limit, which is less than 60 g. It has achieved a reduction in acceleration by 66.116% and zero PCIs even in collisions with different safety ratings cars.</div>

Design and Crashworthiness Analysis of Rear Underrun Protection Device

Each year, thousands of people are passed away due to car accidents. Although technological improvements provided for passenger safety day by day, collision be-tween passenger car and heavy vehicles are still the most dangerous issue. In this pa-per, a new rear underrun protection device was designed. Three different support bracket thicknesses that vary with 4-6 mm whereas investigated and their crash performance and structural integrity were compared to each other. RUPD finite element models were created and analysed for Dodge Neon (1996) collided at 63 km/h vehicle impact speed under full overlap crash scenario. Abaqus/Explicit dynamic analysis that is special tool for highly non-linear Dynamics phenomenon was used for the analyses. Axial deformations, plastic strains, and axial displacement of right seat accelerometer were obtained and compared to evaluating of each design. The optimum support bracket thickness was determined for the new developed RUPD against vehicle colli-sion. The results were also compared to the ref[13] and it is seen that they were good agreement.

Factors influencing injury severity to belted drivers in car crashes in India

Objective The 2019 revised Indian seat belt regulation resulted in a significant increase in driver belt use. This study examines the factors influencing Maximum Abbreviated Injury Scale (MAIS) 2+ injuries to belted car drivers using Indian crash data. Methods Crash data obtained from Road Accident Sampling System–India (RASSI; 2011 to 2020) were used. Analysis was performed on a sample of 662 belted car drivers, representing 1.7 million drivers nationally. Survey logistic regression was used to identify factors influencing the odds of MAIS 2+ injuries to belted car drivers. Factors including delta-V, mass ratio (striking vehicle/struck vehicle), crash type, and driver age and gender were examined. The model fits and the statistical significance of each factor included in the models were examined. In addition, clinical review of crashes with belted drivers sustaining MAIS 3+ injury is presented. Results Delta-V was the most significant factor (odds ratio = 12%; 95% confidence interval 6%–19%) influencing belted driver injuries. Older drivers (55+ years) have a higher odds of MAIS 2+ injury. By adding mass ratio to the model, the odds ratio for delta-V increased to 1.16. If the mass ratio is 2.5 (striking vehicle weight = 2.5 times struck vehicle weight), then the odds of MAIS 2+ injury for the struck vehicle driver doubles. The average Delta-V for MAIS 2+ crashes is 34 mph and injury risk increases significantly when delta-V approaches 30 mph. Seventy percent of crashes with injured drivers had a mass ratio >2. For drivers with minor/no injuries, 88% of crashes had a mass ratio <2. Review of MAIS 3+ injury crashes showed that these crashes had a high delta-V (38 mph) and high mass ratio (5). Sixty percent of belted drivers sustained MAIS 3+ head or chest injury resulting from reduction in survival space. About 37% of AIS 3+ head injuries were subdural hemorrhages and 20% were crush injury to head. AIS 3+ chest injuries were rib fractures (40%) and lung lacerations/ruptures (27%). Conclusion Delta-V and mass ratio are significant factors of belted driver injuries in India. Serious injuries are mainly to the head and chest. Increased rear underrun protection device (RUPD) fitment rate, improved airbag and RUPD design, safe speed enforcement, and improved road infrastructure will reduce injury severity.

Design and Structural Analysis of Trailer Sliding Underrun Protection Device Complied with ECE R58.03 Regulation

In this study, a new, innovative design and structural analysis of trailer sliding rear underrun protection device (RUPD) that complied with UN ECE R58.03 regulation has been made. The technical design norms that determined by United Nations (UN) were considered the key factor for the design parameters. Finite Element Analyses (FEA) were carried out considering the strength test standards specified in the UN ECE R58.03 regulation. Stress distribution was evaluated in the analyzes applied to RUPD. According to stress result of the P1 test condition analysis, the highest stress value was obtained as 839 MPa on hinge mechanism’s pins and also during the P2 condition the stress level on same pins were above 1100 MPa. Considering the stress datas from FEA, it was concluded that the design had to be revised. After revision the stress levels decreased, but levels were close to the yield strength of materials that used. Based on all data obtained, authors decided that design is trustworthy enough to be produced and physical tested, but after the physical testing additional minor revisions may be needed.

Review and Analysis of Technical Designs of Rear Underrun Protective Devices (RUPDs) in Terms of Regulatory Compliance.

The Rear Underrun Protective Device (RUPD) is a basic means to prevent a passenger car from running under the rear of a motor truck (also referred to as heavy goods vehicle or HGV) or a trailer in the case of a rear-end collision and thus to reduce deformations of the car’s passenger compartment (“survival space”). In many publications dealing with such devices, the increasing of RUPD stiffness by applying innovative design solutions or using high-strength materials has been considered; in some designs, additional RUPD components are introduced to absorb the impact energy. In this paper, a review of the RUPD designs is presented and some of them are analyzed, where their characteristics that are essential for the compliance with normative market requirements are indicated. Results of the authors’ research on the selection of an energy absorber incorporated in the rear impact guard bar of an HGV are presented as well.

Design approach of heavy goods vehicle underrun protection using morphological analysis

One of the most harmful of two-vehicle crashes to passenger vehicle occupants is when the front of passenger vehicle hits and passes underneath the rear of truck. It resulted in 23% of total death from two-vehicle crashes with a truck in 2018 based on data from the U.S. Department of transportation’s Fatality Analysis Reporting System (FARS). To reduce the violence of such accidents, the rear underrun protective device (RUPD) is installed on the rear of heavy goods vehicle (HGV), to cause the crumple zone of the impacting passenger vehicle absorbing the impact energy and prevent the impacting passenger vehicle from getting crushed under the HGV. This article demonstrates an approach to design the RUPD based on design inputs, including the structural strength, the local RUPD builders, and the variation of commercial HGV types in Thailand. The morphological analysis is applied along with brainstorming among design team, local manufacturers, and government agency, to generate a total of 72 potential RUPD solutions. In this study, three potential RUPD designs were proposed as RUPD prototypes for different HGV types to investigate their structural strength in terms of strain, deformation, and maximum reaction force. The explicit dynamic finite element (FE) method was implemented to accurately simulate the structural strength of the RUPD prototype since its results were validated by the real test of full-scale prototype with reference to the UN R58 standard. From the results, all proposed RUPD prototypes satisfied the UN R58 standard and are not violated by test loads at all relevant positions. In addition, different designs of the protective beam, which was found to be the main load-bearing resstive component of RUPD, were proposed. Their structural strength and energy-absorbing capability were examined by FE simulation to allow local RUPD builders to have alternatives for RUPD fabrication depending on their resources and applications. Besides, the proposed design approach in this study could be further applied as a guideline design for other RUPD types in a commercial scale.

Design and Development of Truck Rear Underrun Protection Device

Underride truck crashes occur when a passenger car rides under the rear of a large truck. These kinds of accidents are especially dangerous because of the size difference between trucks and passenger cars. Therefore, it is necessary to install the Rear Underrun Protection Device (RUPD) at the rear of trucks for safety enhancement. The aim of this research is to design an effective RUPD which is strong enough to prevent a passenger car falling under the rear of the truck and able to absorb large amount of crash energy to minimize accident severity. The novel RUPD design, equipped with energy absorption guard and proper support structure is proposed in this paper. The study on the angle and separation distance of support structures is performed to find the proper design for the support structure of RUPD. The internal energy and displacement of various design of support structures are investigated by performing Finite element crash simulation in LS-Dyna. The FMVSS 223 standard is utilized as reference for the standard design of RUPD. The result shows that the support structure angle of 20 degree yields optimal displacement and energy absorption. Moreover, the new proposed RUPD is able to avoid the A-pillar deformation and eliminates underride altogether.

Collision simulation and design optimization of rear underrun protection device of lorry

Since most of the heavy-duty lorry rear underrun protective device does not have sufficient blocking capacity to prevent drilling collisions, the casualty rate of small passenger vehicle colliding with heavy trucks is high. Based on the actual participation in road traffic accident identification work, the authors investigated the current installation status and common problems of the rear underrun protective device of heavy-duty lorry. According to the requirements of GB 11567-2017, the authors used LS-DYNA simulation software for a brand of heavy-duty warehouse-type semi-trailers. The mechanical performance model of the rear underrun protective device is studied to provide safety for road traffic and to avoid or reduce the casualties caused by a vicious rear-end collision.

Structural Analysis and Prototyping of Truck Under-run Protection Device

In the present research work we are focusing on side under-run protection devices protect road users such as pedestrians and cyclists from slipping sideways under the wheels of trucks and trailers, and can also improve the aerodynamic performance of heavy vehicles. The basic objective is to improve the safety of the car and the occupants by designing the Rear Under-run Protection Device (RUPD) and car bumper. The choice of material and the structural design are major factors for impact energy absorption during a crash. This study concentrates on component functions, geometry, behavior of material and other parameters that influence the compatibility of the car bumper and rear under run protection device. The analysis was carried out using Finite Elements software SOLIDWORKS. This analysis is a partial work of a major project wherein the RUPD will be subjected to static testing with variable load distributions at different locations on RUPD. After the analysis, the pattern of the part is obtained using Rapid prototyping machine. This can be used for Machining/casting of the original part. Rapid Prototyping (RPT) can be defined as a group of techniques used to quickly fabricate a scale model of a part or assembly using three-dimensional computer aided design (CAD) data.

A response surface approach to heavy duty truck rear underrun protection device beam optimisation

The objective of this paper is to optimise the rear underrun protection device (RUPD) beam design for heavy duty trucks in the interest of impact loading by using correlated finite element analysis. RUPD design is ought to obey the safety regulative rules and shall successfully pass several test conditions. The relation between the RUPD design parameters and the ECE-R58 Regulative Forces is found via the response surface methodology (RSM). Afterwards, the optimum design parameters are determined using a design optimisation procedure. To validate the response surface curve, further analysis is conducted based on arbitrary operating conditions and the calculated and predicted values of ECE-R58 P1 load case forces are compared. In conclusion, the predicted model looks reasonably accurate based on the analysis of variance (ANOVA) method. Using the response curve, one may estimate the degree of P1 load case forces for similar RUPD beam designs using design conditions within the range suggested in the present study.

Crash Simulation of New Car Rear Under-Run Protector

According to a brand of heavy truck’s under protection device, using CATIA surface modeling functions , this article assessed the performance of the rear under-run protection device. Study the performance of the rear under-run protection device by doing width offset collision simulation. A new energy absorption type under-run protection device is designed which can improve the energy absorption property. By vehicle rear-end collision simulations the optimized feasibility of protective devices is verified.

A Kind of Swinging Bumper in the Rear of a Truck and its Performance Research

Using three-dimensional modeling software to design a kind of swinging rear underrun protective device, using the Ansys finite element analysis software, in accordance with the provisions of GB11567.2-2001, the rear underrun protective device applied static load analysis. The results show that the protective device and the body in the welding and bolt connecting two different cases, connected by bolts can effectively avoid the connection of stress concentration, and support as the main part of the force. But by welding, the connections exist obvious stress concentration, may to cause the protective frame dropping.

Analysis and Collision Simulation Research of the Latest Underrun Protective Device

For a truck rear guard device connections is weak, the height from the ground does not meet the national standard. Used CATIA to design the latest kind of swinging truck rear underrun protector. The size of the latest protective frame meet the requirements of Chinese standard GB1567.2-2001. Used the finite element simulation of analysis software LS-DYNA, make the simulation experiment of rear end collision between a car and the truck. Analysis of the curve about the transient dynamic response, displacement, velocity and acceleration of protective frame in the process of collision, Clearly show the deformation process in the rear-end collision process of the protection frame. it proved the effectiveness of the protective frame. Analysis and collision simulation research of the latest underrun protective device.

Design and Optimization of Front Underrun Protection Device

Front Under run Protection Device is tested for car occupant safety by performing Crash analysis with 800 kg (mass of the car) hitting the Front Underrun Protection Device with certain velocity and analyzing its performance and changing design to improve the crash results. Optimization is carried out to improve the crash results for safety of passenger. To reduce number of iterations during the development process, the computational simulation method is used in Front Underrun Protection Device analysis for impact loading. An explicit finite element code like LS Dyna is used for the simulation. This paper explains the FE analysis of Front Underrun Protection Device for impact loading. All the results obtained from the CAE analysis are evaluated against the requirements of IS 14812-2005 which could reduce the process development time and cost. Unigraphics(NX.8) for modeling Front Underrun Protection Device and Preprocessing in Hypermesh and LS DYNA for Crash Analysis (solving), results are viewed in Hyper view.Altair Optistruct is used for weight reduction and change in design of Front under run protection device. In head-on collisions of bonnet-type cars (sedans, wagons, hatchbacks, etc., hereafter referred to simply as cars) and heavy trucks, the car often under runs the front of the truck, and the car crew received the serious or fatal injuries. The crash safety performance of the car depends on the way its structural parts interact with the structural parts of the truck. Front Underrun Protection Device equipment that prevents the car from under running the truck is obligatory in India. The Required strength and ground clearance of FUPDs are specified in the relevant regulations used in India. Accidents between cars and trucks are among the most fatal accidents because of the car under running. This phenomenon leads to serious and fatal injuries for car occupants because of intrusion of the car structure into the passenger compartment. This has led to the development of test procedure for energy-absorbing front under run protection systems for trucks. There is a summary of accident analysis of several European countries, where we can read that of the 48000 fatally injured people in road traffic accidents in 1992, 13000 people were killed in accident with trucks involved, about 7000 were car occupants and 4200 of them were killed in car-to-truck frontal collisions.In the same time, in 1994, a collaboration in France between Renault VI (truck manufacturer) and INRETS has begun. The research program set up is based on a experimental design to determine the effect of the vehicle masses, the overlap and the closing speed and the effect of the Front Under run Protection Device on mechanical and biomechanical characteristics. This experimental design is presented which is also analysed and made available to use as a valid Front Under run Protection Device for trucks. It is very common incident that during the accident a passenger vehicle going under the heavy commercial vehicle either from rear, front or side. During collision, there is a risk that the passenger vehicle will penetrate under (run under) the front or rear part of the truck and thus there are great chances of fatal injuries to the occupants of the passenger car. The study of such statistical data is done by Bjorsting Ulf . The Under-run Protection Device (UPD) is an attachment fixed to the heavy commercial vehicle which will avoid the under running of the passenger vehicles and further reduce the chances of severe fatal injuries to the passenger vehicle occupant. The design and the strength of the Front Under-run Protection Device (FUPD) should be such that it should take the impact load and avoid the under running of the passenger vehicle from the rear of the heavy commercial vehicle. The Indian Standard IS 14812-2005 specifies the requirements of the Front Underrun Protection Device. Physical testing is done with 5 impactors with specific load and sequence; hit the FUPD to evaluate its strength. This scenario is replicated using Finite Element (FE) solvers like Altair Radioss. The load taken by the Front Underrun Protection Device is evaluated using reaction forces. This virtual validation is important for cost saving in the tooling, repetitive testing of the vehicle and cost involved in the same.

Crash Analysis of Front under Run Protection Device using Finite Element Analysis

Under-running of passenger vehicles is one of the important parameters to be considered during design and development of truck chassis. Front Under-run Protection Device (FUPD) plays an important role in avoiding under-running of vehicles from front side of a truck. An explicit finite element software Altair Radio's is used in FUPD analysis for impact loading. The deformation of FUPD bar and plastic strains in FUPD components are determined in the impact analysis for predicting failure of the system to meet the compliance requirements as per IS 14812-2005. Additionally, failure analysis of the FUPD attachment points with chassis is determined. Physical testing can be reduced significantly with this approach which ultimately reduces the total cycle time as well as the cost involved in product development. I. INTRODUCTION In head-on collisions of bonnet-type cars (sedans, wagons, hatchbacks, etc., here after referred to simply as cars) and heavy trucks, the car often under runs the front of the truck, and the car crew received the serious or fatal injuries. The crash safety performance of the car depends on the way its structural parts interact with the structural parts of the truck. FUPD equipment that prevents the car from under running the truck is obligatory in India. The required strength and ground clearance of FUPDs are specified in the relevant regulations used in India. Accidents between cars and trucks are among the most fatal accidents because of the car under running. This phenomenon leads to serious and fatal injuries for car occupants because of intrusion of the car structure into the passenger compartment. This has led to the development of test procedure for energy-absorbing front under run protection systems for trucks. There is a summary of accident analysis of several European countries, where we can read that of the 48000 fatally injured people in road traffic accidents in 1992, 13000 people were killed in accident with trucks involved, about 7000 were car occupants and 4200 of them were killed in car-to-truck frontal collisions. It is very common incident that during the accident a passenger vehicle going under the heavy commercial vehicle either from rear, front or side. During collision, there is a risk that the passenger vehicle will penetrate under (run under) the front or rear part of the truck and thus there are great chances of fatal injuries to the occupants of the passenger car. The design and the strength of the Front Under-run Protection Device (FUPD) should be such that it should take the impact load and avoid the under running of the passenger vehicle from the front of the heavy commercial vehicle. Physical testing is done with 5 impactors with specific load and sequence; hit the FUPD to evaluate its strength. This scenario is replicated using Finite Element (FE) solvers like Altair Radio's. The load taken by the FUPD is evaluated using reaction forces. This virtual validation is important for cost saving in the tooling, repetitive testing of the vehicle and cost involved in the same. The Government of India felt the need for a permanent agency to expedite the publication of standards and development of test facilities in parallel when the work on the preparation of the standards is going on, as the development of improved safety critical parts can be undertaken only after the publication of the standard and commissioning of test facilities. To this end, the Ministry of Surface Transport (MOST) has constituted a permanent Automotive Industry Standards Committee (AISC) vide order No.RT-11028/11/97-MVL dated September 15, 1997. The standards prepared by AISC will be approved by the permanent CMVR Technical Standing Committee (CTSC). After approval, the Automotive Research Association of India, (ARAI), Pune, being the Secretariat of the AIS Committee, has published this standard. For better dissemination of this information ARAI may publish this document on their web site. In Indian vehicles FUPD, still it is not implemented. By this analysis will know that how it can reduce passenger life while impacting to car, pole..Etc. FUPD is designed with the help of European standard dimensions and then will apply the initial velocity from front side and check the strength of the FUPD, if it safe then this thesis is successfully projected. It's a trial and error process. The strategy in selecting a test procedure is to identify tests that have the potential to improve the crash protection provided across a broad range of real-world impact conditions. The crash test conditions, e.g., impact

A comparison of simplex and simulated annealing for optimization of a new rear underrun protective device

In this paper, two optimization approaches to improve the product design process have been analysed. Through the analysis of a case study, concerning the designing of a new High Energy Absorption Rear Underrun Protective Device (HEARUPD), two different optimization approaches (simplex and simulated annealing) have been compared. In the implemented optimization processes, the crash between an economy car and the rear part of a truck has been simulated by dynamic numerical (FEM) analyses. Moreover, authors have proposed the use of a suitable linear function of four variables with the purpose of reducing the multi-objective optimization processes to mono-objective ones. That has been made to simplify the analysis procedures without affecting the quality and the completeness of the optimization processes. The obtained results, as well as showing the high effectiveness of the integrated use of numerical crash analyses and optimization methods, demonstrate that simplex method is more effective than simulated annealing one for optimization problems where the single analysis loop requires much time. Even if the solutions are quite similar in terms of calculated values of the objective function, design and state variables, simplex method needs shorter computational time than simulated annealing to obtain an optimized solution.

Truck frontal underride protection – compatibility factors influencing passenger car safety

Frontal collisions between passenger cars and trucks are the severest vehicle-to-vehicle collisions observed in accident statistics. Regulation 93 was developed to reduce the risk of fatal injury by preventing passenger cars from underriding heavy truck structures. The regulation does not fully address the higher energy of content in these collisions where passenger car structures cannot be expected to have sufficient energy-absorbing capacity. The performance of a front underrun protective device (FUPD) incorporated into a finite element truck model was evaluated and compared with earlier studies by the authors. In particular, structural interaction of the car with the truck structures was investigated. The packing of the FUPD and truck structures was a critical factor for the FUPD performance. It was found that when the vertical offset between the FUPD and truck frame rails is too small, the efficiency of the FUPD is decreased. Incorporating deformable truck frame elements is only beneficial if the offset is at least 220 mm.

Energy-absorbing FUPDs and their interactions with fronts of passenger cars

Structural and in-depth analyses of the crash accidents between heavy goods vehicles and passenger cars showed that the front underrun protective device (FUPD), obeying the Economic Commission for Europe Regulation No. 93, is not sufficient to protect the passenger cars from overriding by heavy goods vehicles in all expected traffic situations. This is based on the expectation that an FUPD will mitigate the severity of these accidents. The unpredictable behaviour of a car during frontal collisions has been identified as a central issue to resolve for FUPD development and testing. On the basis of the findings from the in-depth accident analysis, a simulation matrix was designed and simulations between a passenger car model and a model of FUPD with energy-absorbing elements were run. The goal of the simulations was to understand the theoretical possibilities for energy-absorbing FUPDs and identify some of the critical structural requirements needed to improve frontal crash protection. An analysis of the simulation results showed that a properly activated FUPD with energy-absorbing elements can decrease the severity of the crash by absorbing more than 30% of the total kinetic energy. It was found that the force needed to activate the deformation of FUPD energy-absorbing elements can be used to improve the deformation mode of the car front structure in such a way as to decrease the crash severity.

The optimisation process of an energy absorbing frontal underrun protection device

This paper describes the methodology used during the development of an energy absorbing Frontal Underrun Protection device (eaFUP). The aim of this study is to show how different optimisation methods can be used at different stages during the design process. It also shows one approach to derive an optimal design taking several different design alternatives into account, each of which consists of several different materials. The outcome of the optimisation process is three different designs of the eaFUP.