Influence of Wheels on Frontal Crash Response of Small Lightweight Electric Vehicle

Author(s):  
SongAn Zhang ◽  
Qing Zhou ◽  
Yong Xia

For vehicle frontal crash, the front wheels may affect impact load transfer and load path, and to some extent, the tire deformation may contribute to crash energy absorption. The effects would be especially prominent when it comes to the cases of micro car, offset crash and electric car. For a micro or small car, the front compartment space is small and the wheels are relatively large, and so the wheel’s role on transferring impact load to the A-pillar and the rocker is more significant and the energy absorbed by the tire deformation contributes to a relatively large portion. Moreover, in the case of an offset or small overlap collision, the wheel impacted is apparently engaged at a deeper level than that in full frontal crash. For an electric car when its electric motor is positioned in the rear of the car, the front compartment does not have space-taking engine and so the structural deformation and space use are more affected by the wheels. In this paper, by finite element simulations using a small lightweight electric vehicle (SLEV) model, the above-mentioned aspects are studied. The model has no complex components, and therefore is suitable for parametric study. The influence of the front wheels on the impact load transfer and the energy absorbed by the tire deformation are analyzed. Also front crash results of SLEV are compared with Yaris to show how front wheels affect load path in crash. The results show that the influence of wheels on frontal crash response of small lightweight electric vehicles should not be ignored and should be an integral part of crash safety design.

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Qing-liang Zeng ◽  
Zhao-sheng Meng ◽  
Li-rong Wan ◽  
Cheng-long Wang

To study the load transfer characteristics of a two-legged shield powered support, a numerical simulation model of the support was established using the multibody dynamics software ADAMS. The model took full account of the hydraulic-elastic deformation characteristics of the support, as a series spring-damper system was used to replace the leg and the equilibrium jack. The canopy, goaf shield, lemniscate bars, and equilibrium jack are equivalent to flexible bodies. The setting force of the leg was provided by the preload of the equivalent spring, the static roof load was simulated using a slope signal, and the impact load was simulated using a step signal. Using the model, the impact and excitation effects of each hinge joint of the support were analyzed under different impact load conditions across the canopy. The results show that the location of the impact load affects the force transmissions of all hinge points of the support. Both the impact effect and the excitation effect are at a minimum when the impact force is located near the leg action line. These results are useful for the adaptive control and structural design optimization of the support.


2013 ◽  
Vol 711 ◽  
pp. 149-154 ◽  
Author(s):  
Se Ho Kim

In this paper, a frontal crash analysis is carried out with a full vehicle model in order to investigate the influence of stamping effects of auto-body members on the crash characteristics of the vehicle. Stamping effects are considered for load carrying members such as the front side member and the rear lower. From the analysis result considering stamping effects, it is conformed that stamping history has to be considered for longitudinal members simultaneously that transfer the impact load under the frontal impact. Comparison of simulation result with experimental one also shows that the prediction accuracy of the crash analysis is remarkably improved.


Author(s):  
Michelle Mu¨hlanger ◽  
Patricia Llana ◽  
David Tyrell

To support the development of a proposed rule [1], a full-scale dynamic test and two full-scale quasi-static tests have been performed on the posts of a state-of-the-art (SOA) end frame. These tests were designed to evaluate the dynamic and quasi-static methods for demonstrating energy absorption of the collision and corner posts. The tests focused on the collision and corner posts individually because of their critical positions in protecting the operator and passengers in a collision where only the superstructure, not the underframe, is loaded. There are many examples of collisions where only the superstructure is loaded. For the dynamic test, a 14,000-lb cart impacted a standing cab car at a speed of 18.7 mph. The cart had a rigid striking surface in the shape of a coil mounted on the leading end that concentrated the impact load on the collision post. During the dynamic test the collision post deformed approximately 7.5 inches, and absorbed approximately 137,000 ft-lbs of energy. The SOA collision post was successful in preserving space for the operators and the passengers. For the quasi-static test of the collision post, the collision post was loaded in the same location and with the same fixture as the dynamic test. The post absorbed approximately 110,000 ft-lb of energy in 10 inches of permanent, longitudinal deformation. For the quasi-static test of the corner post, the post was loaded at the same height as the collision post, with the same fixture. The corner post absorbed 136,000 ft-lb of energy in 10 inches of permanent, longitudinal deformation. The series of tests was designed to compare the dynamic and quasi-static methods for measuring collision energy absorption during structural deformation as a measure of crashworthiness. When properly implemented, either a dynamic or quasi-static test can demonstrate the crashworthiness of an end frame.


2018 ◽  
Vol 2018 ◽  
pp. 1-17
Author(s):  
Liangjun Hao ◽  
Weili Gong ◽  
Manchao He ◽  
Yanqi Song ◽  
Jiong Wang

Dynamic model was theoretically established for the two parallel-connected constant-resistance-large-deformation (CRLD) bolts, and the theoretical results were experimentally verified with impact tensile tests on the CRLD bolts samples. The dynamic responses of the double CRLD bolts were investigated under the impact loads with different intensities. The theoretical analyses showed that (1) under relatively small loading the CRLD bolts deform elastically and the deformation finally returns to zero and (2) under the high impact load, including the stable impact load and unstable impact load, the CRLD bolts export structural deformation after the initial elastic deformation. The deformation of the bolts eventually stabilizes at a certain amount of the elongation caused by the relative sliding of the sleeves and rebars. The essential difference between the stable impact load and unstable impact load is that, under the stable impact load, no structural deformation will occur after the impact load ends; under the unstable impact load, the structural deformation will still occur after the impact load ends. The obtained results are of theoretical implications for rock support design with CRLD bolts under the dynamical loading condition.


Author(s):  
Michael Carolan ◽  
David Tyrell ◽  
Brandon Talamini

Research is currently underway to develop strategies for maintaining the structural integrity of railroad tank cars carrying hazardous materials during collisions. This research, sponsored by the Federal Railroad Administration (FRA), has focused on four design functions to accomplish this goal: blunting the impact load, absorbing the collision energy, strengthening the commodity tank, and controlling the load path into the tank. Previous papers have been presented outlining the weight and space restrictions for this new design, as well as the approach being taken in developing the design. The performance goals for the new car have also been outlined. A key goal for the new design is the ability to contain its lading at four times the impact energy of the baseline equipment. Presently, a preliminary design has been developed that will incorporate these four functions together. This new design features a conventional commodity tank with external reinforcements to strengthen the tank. The reinforced tank is situated on a structural foam cradle, within an external carbody. This carbody has been designed utilizing welded steel sandwich panels. The body is designed to take all of the inservice loads, removing the commodity tank from the load path during normal operations. Additionally, the carbody panels will serve as an energy-absorbing mechanism in the event of a collision. Preliminary steps for fabricating and assembling the new tank car design have been outlined. These steps were developed with the intention of paralleling existing tank car fabrication process as much as is practical. Using the commercial finite element analysis (FEA) software ABAQUS/Explicit, the improved design has been analyzed for its response to an impact by a rigid punch. Simulations of two generalized impact scenarios have been made for this rigid punch impacting the improved tank car head as well as the improved tank car shell. Results of these analyses, including the force-displacement curves for both impacts, are presented within this paper. These results show that an improved-design tank car can contain the commodity for a head impact with eight times the energy of the baseline car, and four times the energy for a shell impact.


2011 ◽  
Vol 201-203 ◽  
pp. 272-275 ◽  
Author(s):  
Bao Cong Ma ◽  
Xiang Ke Tian

The traditional method of verifying mechanical and electrical products shock strength is primarily through impact test to the product. From the current experiment the force size and amount of structural deformation can’t be gotten when it suffers from the impact load. Applying the software of MSC.Patran and MSC.Dytran, finite element is modeled for the mechanical and electrical products components, and impact property is analyzed when they are subject to impact load. It can reduce the number of verification test and improve design quality. The application is very promising.


Energies ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3951
Author(s):  
Joanna Baraniak ◽  
Jacek Starzyński

Recently, there has been dynamic development of electromobility. This trend is predicted to grow exponentially, which will contribute to the creation of an extensive infrastructure of electric car charging points. For distribution network operators, this implies that in addition to the increase in demand for power and electricity, the number of converter systems connected to their networks will also increase. It is therefore necessary to determine the potential impact of electric vehicle charging systems on electricity quality. To this end, the authors of the present study developed simulation models based on measurements of the actual charger and the data provided by the manufacturers of the equipment and using simulation models widely described in the literature. On the basis of the study results, the impact of electric car chargers on electric power quality was assessed, and attention was given to the opportunities offered by the development of charging systems with vehicle-to-grid (V2G) functionality. Changes in technical standards aimed at selecting power supply cables by considering their heating under the influence of higher current harmonics generated by converter systems were proposed.


2019 ◽  
Vol 11 (02) ◽  
pp. 1950019 ◽  
Author(s):  
Lin Gan ◽  
He Zhang ◽  
Cheng Zhou ◽  
Lin Liu

Rotating scanning motor is the important component of synchronous scanning laser fuze. High emission overload environment in the conventional ammunition has a serious impact on the reliability of the motor. Based on the theory that the buffer pad can attenuate the impact stress wave, a new motor buffering Isolation Method is proposed. The dynamical model of the new buffering isolation structure is established by ANSYS infinite element analysis software to do the nonlinear impact dynamics simulation of rotating scanning motor. The effectiveness of Buffering Isolation using different materials is comparatively analyzed. Finally, the Macht hammer impact experiment is done, the results show that in the experience of the 70,000[Formula: see text]g impact acceleration, the new buffering Isolation method can reduce the impact load about 15 times, which can effectively alleviate the plastic deformation of rotational scanning motor and improve the reliability of synchronization scanning system. A new method and theoretical basis of anti-high overload research for Laser Fuze is presented.


2021 ◽  
Vol 11 (9) ◽  
pp. 4136
Author(s):  
Rosario Pecora

Oleo-pneumatic landing gear is a complex mechanical system conceived to efficiently absorb and dissipate an aircraft’s kinetic energy at touchdown, thus reducing the impact load and acceleration transmitted to the airframe. Due to its significant influence on ground loads, this system is generally designed in parallel with the main structural components of the aircraft, such as the fuselage and wings. Robust numerical models for simulating landing gear impact dynamics are essential from the preliminary design stage in order to properly assess aircraft configuration and structural arrangements. Finite element (FE) analysis is a viable solution for supporting the design. However, regarding the oleo-pneumatic struts, FE-based simulation may become unpractical, since detailed models are required to obtain reliable results. Moreover, FE models could not be very versatile for accommodating the many design updates that usually occur at the beginning of the landing gear project or during the layout optimization process. In this work, a numerical method for simulating oleo-pneumatic landing gear drop dynamics is presented. To effectively support both the preliminary and advanced design of landing gear units, the proposed simulation approach rationally balances the level of sophistication of the adopted model with the need for accurate results. Although based on a formulation assuming only four state variables for the description of landing gear dynamics, the approach successfully accounts for all the relevant forces that arise during the drop and their influence on landing gear motion. A set of intercommunicating routines was implemented in MATLAB® environment to integrate the dynamic impact equations, starting from user-defined initial conditions and general parameters related to the geometric and structural configuration of the landing gear. The tool was then used to simulate a drop test of a reference landing gear, and the obtained results were successfully validated against available experimental data.


Electricity ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 91-109
Author(s):  
Julian Wruk ◽  
Kevin Cibis ◽  
Matthias Resch ◽  
Hanne Sæle ◽  
Markus Zdrallek

This article outlines methods to facilitate the assessment of the impact of electric vehicle charging on distribution networks at planning stage and applies them to a case study. As network planning is becoming a more complex task, an approach to automated network planning that yields the optimal reinforcement strategy is outlined. Different reinforcement measures are weighted against each other in terms of technical feasibility and costs by applying a genetic algorithm. Traditional reinforcements as well as novel solutions including voltage regulation are considered. To account for electric vehicle charging, a method to determine the uptake in equivalent load is presented. For this, measured data of households and statistical data of electric vehicles are combined in a stochastic analysis to determine the simultaneity factors of household load including electric vehicle charging. The developed methods are applied to an exemplary case study with Norwegian low-voltage networks. Different penetration rates of electric vehicles on a development path until 2040 are considered.


Sign in / Sign up

Export Citation Format

Share Document