Rear Bumper Research Articles

Unveiling the Future of Safety: Cutting-Edge Simulation Testing of e-Kart Bumpers

Abstract This research project proves the importance of simulation technology in developing safe and efficient components for electric Go-Kart and how this approach could impact the future of automotive design and engineering. The development of electric Go-Kart present unique challenges in ensuring safety and performance, given the increasing demand for eco-friendly mobility solutions in motorsports. As the adoption of the electric vehicles grow, the importance of designing robust and reliable safety components, such as bumpers, become critical to protect drivers and enhance vehicle durability. While previous studies have explored Go-Kart safety and performance, they often relied on traditional testing methods that are time-consuming and limited in their ability to simulate complex crash scenarios. Moreover, many studies have not fully addressed the specific challenges associated with the unique dynamics of electric Go-Kart. This research fills these gaps by focusing on testing electric Go-Kart bumpers through advanced computer simulations used to thoroughly examine various crash and impact scenarios to assess the reliability and durability of the front, side and rear bumpers to improve safety and performance. The results of the stress analysis carried out on the electric Go-Kart body showed that the electric go-kart body experienced displacement and safety factors, with the stress experienced being at a point below the yield strength or yield strength so that the body construction was declared safe against the static loading received, so that the test results this provides detailed insight into material strength, structural design, and possible improvements that can be made to reduce the risk of rider injury.

Finite element analysis regarding folding behaviour of different crashbox versions

Low-speed collision is one of the most frequent road accident types nowadays. The consequences of this accident could be serious and long terminated. The passive safety system has an important role to reduce and prevent the amount of personal and technical injuries. Applying front and rear bumper beams is a good way to absorb more impact energy at the moment of collision reducing the load of the occupants. The background of the energy absorbing is the prescribed folding deformation of the bumper's support namely the crashbox. The main goal of the present study is to evaluate and compare differently shaped crashboxes as a thin-walled structure using finite element analysing to get information for more effective energy absorption taking into consideration of the weight optimization and spce requirements. To be comparable to the folding fluctuation of each specimen the compression test's curves are evaluated with relative standard density. Moreover, the specific energy absorption is also was determined. Based on the values determined by finite element analysis conclusions could be drawn.

Optimisation of hybrid composite shields for hypervelocity Micro-Meteoroid and Orbital Debris (MMOD) impact

Advancements in space exploration over the last few decades have led to a sharp increase in Micro-Meteoroid and Orbital Debris (MMOD), with the associated increased risk of hypervelocity impact on satellites and space structures. The Whipple shield can mitigate the effects of such impacts and current research is exploring further developments towards effective lightweight passive shielding technology to counter the damaging effects of MMOD. With the increase in MMOD and the prospect of increased space travel in the coming years and decades, it is vital that more research is conducted and improvements are made in the development and design of efficient, lightweight shielding technology to protect both unmanned and manned spacecraft against hypervelocity impacts (HVI). The optimisation of shield design for HVI is a high dimensionality problem, suited to advanced computational approaches. Key variables in HVI shield design that should inform the focus on optimisation include: impact velocity, rear wall thickness, projectile diameter and bumper thickness. A hybrid shield configuration and numerical model are proposed and validated, with alternating layers of aluminium (AL2024) and carbon fibre composites (CFRP, T300 woven-fabric) to form a 5 mm thick target plate consisting of 5 plies. The adaptive coupled FEM-SPH method is used to model the target plates. The proposed hypervelocity shield design optimisation methodology is based on Direct Simulation-based Genetic Algorithm (DSGA) optimisation and is implemented to optimise a multi-variable shield design space. Objective weightings are used to analyse and discuss results, referring to the ratio of the kinetic energy to the shield areal density objectives. A clear transition in the impact behaviour of the optimised MMOD shields is observed in the transition region from high-velocity to hypervelocity impact, where significant levels of kinetic energy dissipation are observed below the transition region, and lower energy dissipation at hypervelocity. The shield design optimisation results show that with a weighted kinetic energy to mass objective of 90:10, the kinetic energy of the back shield plate decreases significantly (62.7%) and the areal density can be reduced by more than 18%. Alternative configurations displayed sub-optimal results based on a trade-off between objective functions.

Load distribution structure of rear bumper beam to enhance vehicle body energy absorption in rear-end collisions

Objective This research focused on FMVSS301, which is required for higher energy absorption as a regulation for rear-end collisions. Since they are offset collisions, the deformation of the non-collision side frame, which does not directly contact the barrier, is less than on the collision side. The reason is that the rear bumper beam with curvature is deformed into a straight shape by the load from the barrier, resulting in an asymmetrical load distribution from the barrier that is biased toward the collision side. Therefore, the objective of this research was to construct a new bumper beam structure that reduces the difference in the load input to both frames and increases the energy absorption of the non-collision side frame. Method The basic principle is to generate a counterforce against the lateral loads during transmitting the load from barrier to the frames. To achieve this, a bow-shaped rear bumper beam structure was devised. The rear bumper beam corresponds to the bow and the newly added connection plate to the string. The lateral load increase is suppressed and load distribution to the rear frame is maintained. Results The designed rear bumper beam and rear components equipped with the rear bumper beam were both prepared and evaluated by drop test. With testing of the rear bumper beam, it was demonstrated that the load in the lateral direction, which conventionally generates over 80 kN, could be canceled. Tests of the rear component demonstrated that load distribution to the rear frame could be maintained, and the energy absorption of the non-collision side frame could be enhanced by 35 times. The total energy absorption of the barrier and the two frames was demonstrated to increase 2.9 times. Conclusion The bow-shaped rear bumper beam was designed to distribute the load evenly to the collision and non-collision side frames, and to deform both frames, thereby achieving a higher energy absorption of the entire vehicle body. This is expected to be applicable to electric vehicles and FCVs, which require more energy absorption with increased vehicle weight.

Study on Corrosion Behavior and Mechanism of Ultrahigh-Strength Hot-Stamping Steel Based on Traditional and Compact Strip-Production Processes.

Hot-stamping steel is a type of high-strength steel that is mainly used in key safety components such as the front and rear bumpers, A-pillars, and B-pillars of vehicles. There are two methods of producing hot-stamping steel, i.e., the traditional process and the near net shape of compact strip production (CSP) process. To assess the potential risks of producing hot-stamping steel using CSP, the microstructure and mechanical properties, and especially the corrosion behavior were focused on between the traditional and CSP processes. The original microstructure of hot-stamping steel produced by the traditional process and the CSP process is different. After quenching, the microstructures transform into full martensite, and their mechanical properties meet the 1500 MPa grade. Corrosion tests showed that the faster the quenching speeds, the smaller the corrosion rate of the steel. The corrosion current density changes from 15 to 8.6 μA·cm-2. The corrosion resistance of hot-stamping steel produced by the CSP process is slightly better than that of traditional processes, mainly since the inclusion size and distribution density of CSP-produced steel were both smaller than those of the traditional process. The reduction of inclusions reduces the number of corrosion sites and improves the corrosion resistance of steel.

Clinician’s Corner: The Canadian Cervical Spine Rule

A 44-year-old driver of a small sedan self-presents to your emergency department (ED) triage area indicating they developed a stiff neck 30 minutes after they were rear-ended by a small van when they were stopped at a traffic light. The rear bumper of the patient’s vehicle is slightly dented, and there is scuffing to the front bumper of the van. No airbags were deployed and the driver of the sedan did not hit their head. The van was estimated to be travelling between 10-20 km/h at the time of impact. The patient self-extricated from their vehicle and was ambulatory at the scene. Currently, the patient is alert, oriented, and in no distress. The patient denies paresthesia, has no midline cervical spine (c-spine) tenderness, and is able to actively rotate their neck 45° left and right.

A Study on Small Vehicle Structure in Rear Under-Ride Impact by Using A CAE Based Methodology

This study simulated and evaluated the safety of a small car structure in a collision with the rear of a truck. The parameters of bumpers currently used in Vietnam were employed to build a model of the rear truck bumper. The setting of simulation conditions was based on the NCAP (New Car Assessment Program) crash test. According to actual crash conditions, a collision simulation was performed with different vehicle speeds from 40 to 60 km/h, corresponding to the case of a passenger vehicle moving in a city colliding with a truck standing still. In addition, the percentage of rear-end collision was also taken into account, just like in real-world collisions, at 25%, 50%, and full rear impact. The simulation results were analyzed and evaluated according to the IIHS rating (Institute Insurance for Highway Safety). The results from different case studies showed that the rear bumper typically used on trucks is only safe for passenger cars in a collision at a low speed of 40 km/h and that in a collision at a higher speed will affect the passenger’s safe space and cause high injuries and casualties. Therefore, it is necessary to improve safety by optimizing the rear bumper design and the frontal structure of the small car chassis.

The effect of canard’s optimum geometric design on wake control behind the car using Artificial Neural Network and Genetic Algorithm

Canard is a cutting-edge aerodynamic attachment for lowering the vehicle’s drag coefficient by efficiently directing the airflow as well as reducing the lift coefficient by enhancing down-force. This paper aims to simulate the airflow crossing over the car to investigate the effect of canards’ geometric design on the rear-body wake using the application of CFD-based optimization. Hence, 7 design variables based on the geometry of the canard are considered, and the objective functions are set to be drag and lift coefficients that are aimed to be minimized. Firstly, ANSYS Fluent is utilized to generate CFD calculations for a series of Design of Experiment (DOE) points. Then, the GMDH-ANN processes the results to elicit the polynomials that demonstrate the relation of design variables and objective functions. A genetic algorithm is next implemented for multi-objective optimization using polynomials as its input, and consequently, Pareto optimal points are achieved. The numerical results show that an appropriate design for canards on the rear bumper causes a potential drag and lifts reduction of 9.62% and 9.6% in comparison to the car without canards. Moreover, the size of the wake behind the car decreases and the differences in the pressure distribution between car fore-body and rear-body is reduced. Finally, the fuel efficiency is potentially enhanced due the changes in car drag coefficient and frontal area.

Estimating the Workload of Driving Using Video Clips as Anchors

<div class="section abstract"><div class="htmlview paragraph">As new technology is added to vehicles and traffic congestion increases, there is a concern that drivers will be overloaded. As a result, there has been considerable interest in measuring driver workload. This can be achieved using many methods, with subjective assessments such as the NASA Task Loading Index (TLX) being most popular. Unfortunately, the TLX is unanchored, so there is no way to compare TLX values between studies, thus limiting the value of those evaluations. In response, a method was created to anchor overall workload ratings. To develop this method, 24 subjects rated the workload of clips of forward scenes collected while driving on rural, urban, and limited-access roads in relation to 2 looped anchor clips. Those clips corresponded to Level of Service (LOS) A and E (light and heavy traffic) and were assigned values of 2 and 6 respectively. Subjects said if they would perform any of 3 tasks—dialing a phone, manually tuning a radio, or entering a destination—while they were driving in each test scene. Finally, subjects provided other ratings for a wider range of situations (not shown in clips) to further examine the effects of road geometry, traffic, and other factors on workload. For each clip, vehicle dynamics data were available for the driven vehicle and the relationship of that vehicle to those in the scene. Using regression analysis, the rated workload (averaged across subjects) was estimated to be 8.87 - 3.01(LogMeanRange)+ 0.48(MeanTrafficCount)+ 2.05(MeanLongitudinalAcceleration), which accounted for 87% of the ratings, an extremely high value. In that expression, range is the distance from the subject’s front bumper to the lead vehicle rear bumper, mean traffic count is the mean number of vehicles visible in the road scene to radar, and the mean acceleration is that of the subject vehicle.</div></div>

Finite Element Simulation of Dent Resistance For Automotive Rear Bumper

In automotive industry, there is an increasing demand for weight reduction. On the other hand extraordinary style for automotive exteriors are used in order to increase number of sales. As a result, the usage of different shapes for exterior bumpers is getting increased. Because of that, finite element simulation of dent resistance for automotive bumpers has become a very important step in early steps of automotive design. In this paper, static dent resistance for automotive exterior rear bumper is investigated by using nonlinear finite element method. The thickness change for different areas of bumper is considered from CAD data. In addition, nonlinear mechanical properties such as plastic behavior of rear bumper material are used in the finite element simulations. In addition, the results that are obtained from physical test are also presented here to compare with the results of finite element simulations to see percentage of correlation. This study is mainly focused on the correlation between finite element simulations and physical test results. The finite element simulation results show us that the percentage of correlation with the physical test results is reasonable. Consequently, due to high percentage of correlation between nonlinear finite element results and physical test results, the nonlinear finite element results should be taken into account in early steps of automotive design in order to reach minimum cost and get the most robust solution to eliminate quality problems which may occur in the future.

Mining patterns of autonomous vehicle crashes involving vulnerable road users to understand the associated factors

Autonomous or automated vehicles (AVs) have the potential to improve traffic safety by eliminating majority of human errors. As the interest in AV deployment increases, there is an increasing need to assess and understand the expected implications of AVs on traffic safety. Until recently, most of the literature has been based on either survey questionnaires, simulation analysis, virtual reality, or simulation to assess the safety benefits of AVs. Although few studies have used AV crash data, vulnerable road users (VRUs) have not been a topic of interest. Therefore, this study uses crash narratives from four-year (2017–2020) of AV crash data collected from California to explore the direct and indirect involvement of VRUs. The study applied text network and compared the text classification performance of four classifiers - Support Vector Machine (SVM), Naïve Bayes (NB), Random Forest (RF), and Neural Network (NN) and associated performance metrics to attain the objective. It was found that out of 252 crashes, VRUs were, directly and indirectly, involved in 23 and 12 crashes, respectively. Among VRUs, bicyclists and scooterists are more likely to be involved in the AV crashes directly, and bicyclists are likely to be at fault, while pedestrians appear more in the indirectly involvements. Further, crashes that involve VRUs indirectly are likely to occur when the AVs are in autonomous mode and are slightly involved minor damages on the rear bumper than the ones that directly involve VRUs. Additionally, feature importance from the best performing classifiers (RF and NN) revealed that crosswalks, intersections, traffic signals, movements of AVs (turning, slowing down, stopping) are the key predictors of the VRUs-AV related crashes. These findings can be helpful to AV operators and city planners.

PEMANFAATAN KICK FOOT SENSOR UNTUK MEKANISME BUKA TUTUP BAGASI KENDARAAN

Along with its development, car manufacturers are increasingly improving safety and security features in each of their products. Currently, this element of safety and security has become an important target in the development of the existence of various features that exist in a vehicle. In this study, the power back door feature is implemented by using the kick foot sensor as input data to open and close the trunk of the vehicle through the actuator. This feature uses a foot sensor so you don't have to press any buttons, just point your foot under the rear bumper and the sensor will automatically read and open the trunk door. This feature is very helpful for passengers who want to put their luggage in the trunk but have both hands to carry items such as bags or plastic shopping bags. There are several stages carried out in this research. In the first stage, the specification of the required actuator motor, including force and torque, is carried out by analyzing the free body diagram to be able to open and close the trunk. In the second stage, the trunk door is tested when the condition is open and close. From the test results, the average time to open the trunk is 11.79 seconds, while the average time to close the trunk is 11.56 seconds. The time obtained is faster than the initial design target set, which is 15 seconds both when opening and closing the trunk. While the sensitivity of the motion sensor can range from 20 mm to 400 mm when the foot is directly under the sensor.

‘Time is Money’: Dar es Salaam’s Daladala Inscriptions and the Ethics of Everyday

ABSTRACT In Dar es Salaam, privately-owned minibuses, known as daladalas, are the most popular means of commuting. Their routes crisscross the city and the minibuses themselves are adorned with messages and inscriptions on their rear bumpers. These inscriptions comment on aspects of city life, forming a significant corpus of urban scripts. Three main categories emerge from this corpus: work, money and time. In this paper, I show how these three categories are intimately connected and can be read as an intertextual body of urban scripts commenting on the ethics of everyday life in the city. Reading these inscriptions as authorless texts, produced and interpreted by the city, I examine how they offer a nuanced yet ambivalent representation of Dar es Salaam. The three themes act as nodes around which images of and metaphors for city life in Dar es Salaam are articulated. This paper sheds light on how we can read these pithy and ubiquitous texts as an archive which comments upon what it means to live in Dar es Salaam and the ethics of city life.

Minimizing Warpage and Shrinkage of Plastic Car Rear Bumper Fabrication via Simulation Based Optimisation

Car bumpers are designed to absorb small impacts, such as accidentally bumping into another car while backing off a parking spot, not major road accidents. As to make it lighter, plastic is the best available material. To fabricate it by injection molding, thin-wall and complex parts such as car bumper might create a lot of defects such as shrinkage and warpage. So, the stronger plastic material and correct optimized parameters should be applied. Butadiene Styrene (ABS) is selected in this study. This project aims to optimize the injection moulding process parameters of plastic car bumper by using Central Composite Design (CCD) in Response Surface Methodology. Mould temperature, melt temperature, injection time are selected as factors to be studied. As the results, the optimum values suggested by the software were mould temperature of 25°C, 226.36°C melt temperature and 1.88s injection time. The best material suggested is ABS. With small differences in error value between solution and simulation, 0.895% of shrinkage and 10.3% for warpage, the results were acceptable.

Mechanical properties of polyester composite reinforced fibers hybrid bamboo - Musa acuminata stem fiber as raw material of rear bumper vehicle

Mechanical properties of polyester composite reinforced fibers hybrid bamboo - Musa acuminata stem fiber as raw material of rear bumper vehicle

Mechanical properties of polyester composite reinforced fibers hybrid bamboo - Musa acuminata stem fiber as raw material of rear bumper vehicle

In the present study fiber hybrid (bamboo fiber and Musa acuminata stem fibers (MASF) were reinforced polyester composite, for enhancing mechanical properties. The natural fibers composite has gained its importance due to its low cost, substitute for artificial fiber, low price, able to reduce sound, environmentally friendly, has a low density, good fit and ability to absorb impact energy. It’s possible to use it as a vehicle accessory such as a rear bumper vehicle. This study aims to investigate the tensile stress-strain, elasticity modulus and the microstructure of fracture of polyester fiberglass composite reinforced bamboo fiber and MASF hybrid. Polyester matrix type 157 is used BQTN and G3253T, MEKPO catalyst. The mechanical properties test was carried out by universal testing machine (UTM) test instrument, observing the microstructure of the occurrence of fracture by using scanning electron microscope (SEM). The test specimens produced the vacuum infusion method. The results of this study indicate that the addition of more MASF and the outer layer content can increase the tensile strength, elasticity modulus of polyester composites reinforced MASF with woven, random arrangement is better than that of polyester composites reinforced bamboo fiber. So that in the manufacture of polyester composites reinforced hybrid fiber the use of more MASF than bamboo fiber can provide better tensile strength and elasticity modulus. The configuration with the outer MASF layer can also increase the value of tensile strength, elasticity modulus on the specimen compared to the configuration with bamboo fiber outside. The microstructure of fracture for fiber for each configuration of MASF content there are long fibers and also in bamboo fibers there are fibers that are pulled out. The diameter of the bamboo fiber reinforcement is larger so that the load transfer is not as effective as MASF.

Characterization of graphene nanoplatelets reinforced sustainable thermoplastic elastomers

Elastomer nanocomposites have attracted tremendous attention in recent years owing to their exceptional mechanical, electrical, thermal barrier and flame-retardant properties. Graphene has become a prevalent constituent in elastomer nanocomposites thanks to its superior stiffness and strength, as well as its potential to enhance multifunctional properties. In this study, sustainable thermoplastic elastomers based on recycled polypropylene (RPP) and renewable guayule latex, which has recently entered the commercial arena as an alternative natural rubber, were prepared with polypropylene-grafted-maleic anhydride as a coupling agent. Graphene nanoplatelets (GnP) (2.5–10% by wt.) were added to enhance the mechanical (strength and modulus), thermal and flame retardant properties. With the addition of 10% GnP, the flexural modulus increased by a factor of 1.24, whereas tensile modulus increased by 76%. Scanning electron microscopy of the fractured surface of GnP reinforced nanocomposites showed a good correlation with the improvements in impact properties. Thermogravimetric analysis of composites with 10% GnP showed an increase in carbon residue at 600°C by a factor of 3.4 indicating improved thermal stability. Incorporation of GnP did not have a significant effect on the glass transition temperature range, however, the magnitude of storage modulus increased significantly. As expected, incorporation of GnP increased the shear viscosity, which decreased with shear rate exhibiting non-Newtonian behavior. These results indicate that GnP reinforced composites could be used in the next generation of automotive thermoplastic elastomer products such as cowl vent grills, wheel lips, rear bumper fascia, rocker panels and side moldings with certain improvements in mechanical, thermal and physical properties.

Study of tensile strength and morphology of polyester matrix composite materials reinforced Hibiscus tiliaceust bark powder as raw material of rear bumper vehicle

Study of tensile strength and morphology of polyester matrix composite materials reinforced Hibiscus tiliaceust bark powder as raw material of rear bumper vehicle

Study of tensile strength and morphology of polyester matrix composite materials reinforced Hibiscus tiliaceust bark powder as raw material of rear bumper vehicle

Fibrous composite materials continue to be researched and developed with the long-term goal of becoming an alternative to metal substitutes. Due to the nature of the fiber reinforced composite material, its high tensile strength, and low density compared to metal. In general, the composition of the composite consists of reinforcing fibers and a matrix as the binding material. The potential of natural fibers as a reinforcing composite material is still being developed and investigated. The research that has been done aims to determine the characteristics of the tensile strength of the composite strengthened with Hibiscus tiliaceust bark powder (HTBP) with alkaline NaOH and KOH treatment. The reinforcing material used is HTBP and the matrix is polyester resin, with volume fraction of 5%, 10% and 20% with an alkaline treatment of 5% NaOH and 5% KOH with immersion for 2 hours, 4 hours, 6 hours and 8 hours. Tensile testing specimens and procedures refer to ASTM D3039 standard. The results of this study showed the highest tensile strength of 34.96 MPa in the alkaline treatment of 5% KOH, soaking time of 8 hours with a volume fraction of 10% and the lowest tensile strength of 21.96 MPa of 5% KOH alkaline treatment, soaking time of 6 hours with a volume fraction of 20%. .with 10% volume fraction of 34.96 MPa and the lowest tensile strength was 5% KOH alkaline treatment at 6 hours immersion with 20% volume fraction.

Study of the Measurement of Generation 2 Toyota Event Data Recorders in Low-Speed Side Impacts

<div class="section abstract"><div class="htmlview paragraph">Automotive Event Data Recorders (EDRs) are often utilized to determine or validate the severity of vehicle collisions. Several studies have been conducted to determine the accuracy of the longitudinal change in velocity (ΔV) reported by vehicle EDRs. However, little has been published regarding the measurement of EDRs that are capable of reporting lateral ΔVs in low-speed collisions. In this study, two 2007 Toyota Camrys with 04EDR ECU Generation modules (GEN2) were each subjected to several vehicle-to-vehicle lateral impacts. The impact angles ranged from approximately 45 to 135 degrees and the stationary target vehicles were impacted at the frontal, central, and rear aspects of both the driver and passenger sides. The impact locations on the bullet vehicles were the front and rear bumpers and the impact speeds ranged from approximately 7.9 to 16.1 km/h. Instrumentation was mounted at the approximate center of gravity (CG) of the target vehicles, as well as on the front reinforcement bar, rear body panel, airbag ECU, B-pillars, and C-pillars to evaluate the varying lateral ΔV (ΔV<sub>y</sub>) readings from the 3 sensor locations (ECU, B-pillar, C-pillar) represented in the Toyota EDR and to account for rotational (yaw) effects on the data. The lateral ΔVs reported by the Toyota EDRs were then compared to the recorded ΔV<sub>y</sub>s from the reference instrumentation mounted within the test vehicles. A comparison of the data revealed a general under-reporting of impact severity from the Toyota EDRs at the ECU sensor when compared to reference instrumentation at the vehicle CG for impacts near the center of the target vehicle where the vehicle typically rotated about its frontal aspect. There was a general over-reporting of impact severity from the Toyota EDRs at the ECU sensor when compared to reference instrumentation at the vehicle CG for impacts near the front (heavy) axle of the target vehicle where the vehicle rotated about its rear aspect. Rotational data from the reference instrumentation and the distance between the ECU and reference instrumentation at the CG was also utilized to calculate the corresponding ΔV<sub>y</sub> at the ECU location for a direct comparison to the Toyota EDR measurement at the ECU (maximum of 12.0% difference). A comparison of the data recorded at the Toyota ECU sensors and the reference instrumentation mounted to the ECUs revealed accurate measurements by the Toyota ECU sensor (maximum of 7.6% difference). Differences in reported values between the 3 aforementioned Toyota sensor locations, as well as non-recordings and longitudinal ΔV recordings from the Toyota EDRs were also evaluated.</div></div>