Browse Topic: Vehicle body pillars
ABSTRACT In order to defeat under body blast events and improve crew survivability, a monocoque aluminum cab structure has been designed as a drop on solution based on the current M1151A1 (HMMWV) chassis. The structure is comprised of all 5083-H131 Aluminum alloy armor plates with various thicknesses. The structure design consists of the following new features: (1) Robust joining design utilizing interlocking ballistic joints and mechanical interlocking features, (2) unique B-pillar gusset design connects roof & floor with B-pillar & tunnel, and (3) “Double V” underbody shaping design. The TARDEC designed, integrated & built vehicle achieved no crew core body injuries for a vehicle of this weight class and demonstrated meeting the crew survivability objective when subjected to a 2X blast during the live fire underbody blast tests. These efforts help to not only baseline light tactical vehicle capabilities, but also validate the possibility of meeting aggressive blast objectives for
In the early stages of vehicle development, it is critical to establish performance goals for the major systems. The fundamental modes of body and chassis frames are typically assessed using FE models that are discretized using shell elements. However, the use of the shell-based FE method is problematic in terms of fast analysis and quick decision-making, especially during the concept phase of a vehicle design because it takes much time and effort for detailed modeling. To overcome this weakness, a one-dimensional (1D) method based on beam elements has been extensively studied over several decades, but it was not successful because of low accuracy for thin-walled beam structures. This investigation proposes a 1D method based on thin-walled beam theory with comparable accuracy to shell models. Most body pillars and chassis frame members are composed of thin-walled beam structures because of the high stiffness-to-mass ratio of thin-walled cross sections. However, thin-walled cross
Blind spots created by the driver-side B-pillar impair the ability of the driver to assess their surroundings accurately, significantly contributing to the frequency and severity of vehicular accidents. Vehicle manufacturers cannot readily eliminate the B-pillar due to regulatory guidelines intended to protect vehicular occupants in the event of side collisions and rollover incidents. Furthermore, assistance implements utilized to counteract the adverse effects of blind spots remain ineffective due to technological limitations and optical impediments. This paper introduces mechanisms to quantify the obstruction caused by the B-pillar when the head of the driver is facing forward and turning 90°, typical of an over-the-shoulder blind spot check. It uses the metrics developed to demonstrate the relationship between B-pillar width and the obstruction angle. The paper then creates a methodology to determine the movement required of the driver to eliminate blind spots. Ultimately, this
Contemporary power boxes (or feeder pillars, as they are known outside of the U.S.) are mounted in the street and control the electrical supply to dwellings within a neighborhood. As residents increasingly prioritize the aesthetic and continue to place a high value on urban living, there is a need for less conspicuous power boxes
In the late 1970’s and early 1980’s, Jing-Yau Chung along with Joseph Pope published several external General Motors reports on the then novel measurement of sound intensity (SI) using the two-microphone, cross-spectral method. Application of this measurement method was then extended to sound intensity measurements in flow. Through component wind tunnel measurements, it was determined that the intensity of noise sources could be accurately measured up to a level of 15 dB below the sound pressure level generated by flow noise on microphones. An initial application of this method was to the identification of noise sources alongside rolling truck tires. It was then extended to the measurement of the aerodynamic noise generated by protrusions added to automotive vehicle designs. These included items such as outside rearview mirrors, windshield wipers, A-pillar offsets, grille whistles, roof racks, underbodies, and fixed-mast radio antennas. Many of these could be applied on the early full
In this article, the method based on the combination of the acoustic perturbation equations and the statistical energy analysis has been used to simulate and optimize the interior aerodynamic noise of a large sport utility vehicle model. The reliability of the method was verified by comparing the analysis results with the wind tunnel test. Influenced by the main noise sources such as A-pillar, exterior rearview mirror, and front sidewindow, the wind noise of the model was significantly greater than that of the same class. To improve the wind noise performance, the side mirror was optimized with the method, including the minimum distance between the rearview mirror and the triangle trim cover, the angle between the rearview mirror and the front sidewindow, and the shell groove of the rearview mirror. The simulation results show that the overall sound pressure level in the car decreases by 2.12 dBA and the articulation index increases by 4.04% after optimization. The development target
This paper deals with vehicle door 120-degree joint rust issue and water leak faced in most of SUV cars. Generally based on vehicle segment its styling curves and exterior design are defined. A Sedan or Hatchback is provided with curves to show its fluidic design but a SUV is provided with Straight lines to show its aggressive look. In existing condition door frame Joint has sharp joints where weld bead is added to prevent rust in joint area, but still improper seating of weather strip on weld bead cause water leak. Door’s A Pillar Frame and Horizontal Frame match at 120 degree joint edges are chamfered straight to match perfectly. Weld bead runs over the matching profile to join it. But weld bead project over the Frame surface and affects weather strip seating & results in poor sealing. Adhesive added for better sealing also follows the same path on bead and create a path way for water entry. Thus in long run this water stagnates and cause chronic rust issues in frame. This in turn
Aesthetics contribute significantly to the customer’s buying decision of an automobile. This is traditionally achieved through painting. Sustainability and cost challenges have led automakers to look at substituting painting through molded-in color polymers in decorative bezels like pillar appliques. These appliques and bezels have a unique mix of material requirements that include color tone, gloss, stiffness, scratch resistance and weathering. Polycarbonates are an interesting class of polymers that has the potential to meet these challenging requirements. This paper reports the work done in evaluating a polycarbonate compound in piano black shade to meet the functional and aesthetic requirements. The results prove that the material can substitute painting thereby resulting in significant cost savings. This is a ready to mold material used in injection molding process. This modified polycarbonate material has been explored for thin wall appliques and bezels with thickness of 2.7 mm
This paper aims at providing the scientific community with an overview of the H2020 European project 3beLiEVe and of its early achievements. The project has the objective of delivering the next generation Lithium-Nickel-Manganese-Oxide (LNMO) battery cells, in line with the target performance of the “generation 3b” Li-ion battery technology, as per EU SET-plan Action 7. Its activities are organized in three main pillars: (i) developing the 3b next generation LMNO battery cell, equipped with (ii) an array of internal and external sensors and complemented by (iii) manufacturing and recycling processes at scale. At present, 3beLiEVe is approaching the completion of its first project year (out of a total project planned duration of 42 months). Hence this paper, beyond presenting the overall project’s structure and objectives, focuses on its earliest results in the fields of the cell material formulation, arrangement of sensors and design of the battery pack
Automakers generally recommend not to weld structural parts after a vehicle crash, and these should be replaced as a whole part in case of a crash event. Sectioning of these members is also not recommended and use of the repair manual is mandatory in case of fracture of such parts. However, repair shops may not adhere to these instructions and use incorrect repair procedures on these members which would modify their strength properties. This study analyses the impact of welding structural members in a vehicle like the A-pillar which use Ultra-High Strength Steels (UHSS) for reducing the weight of the vehicle and improving the crashworthiness of the structure. The research conducted in this paper highlights the differences in the crash performance of a repaired vehicle as opposed to baseline injury values for the vehicle. The performance of the modified vehicle when tested for different loadcases shows reduced crash performance as compared to the baseline performance and it can be
Based on the characteristics of high strength and modulus of carbon fiber-reinforced composite (CFRP), in this article, the CFRP material was used to replace the steel material of the automobile’s B-pillar inner and outer plates, and the three-stage optimization design of the lamination structure was carried out. Firstly, this article used the principle of equal stiffness replacement to determine the thickness of the carbon fiber B-pillar inner and outer plates, and the structural design of the replaced B-pillar was also carried out. Secondly, on the basis of the vehicle collision model, the B-pillar subsystem model was extracted, and the material replacement and collision simulation were carried out. Thirdly, the free-size optimization, size optimization, and lamination sequence optimization of the CFRP B-pillar were performed to get the best ply structure; the objective of optimization was to minimize the carbon fiber B-pillar inner and outer plates mass, and the constraint
This work presents a new design of ventilation pillars in ventilated brake discs. The use of National Advisory Committee for Aeronautics (NACA) aerodynamic profiles is proposed. Of the references consulted, there is no standard or procedure that indicates how the pillars should be installed in the ventilated discs. Therefore, it is proposed using the Kaplan’s error triangles theory of turbo hydraulic machinery to have a geometrically orderly way of placing the NACA 66-209 profiles from the suction diameter to the discharge diameter. To validate this new design, a 1:1 scale acrylic disc model was constructed, and tests were conducted in water using the particle tracking velocimetry technique to characterize the water model. The water experiment was performed at test speeds of 35, 41, 48, and 54 rpm. From the experiment in water, it is possible to visualize the flow field from the suction diameter to the model discharge diameter and scale the results to the prototype in air. Being 54 rpm
Head injuries are the main source of road fatalities when a pedestrian or other vulnerable road user (VRU) such as cyclist or motorcyclist is involved in an accident with the approaching high speed vehicle. The frontal part of a car such as engine hood (bonnet), lower-windshield area and A-pillars are the possible location of head impact in these accidents. The head impact with hard points located in these areas may result in the fatal head injuries. The effect of impact can be reduced by using the deployable pedestrian protection systems (DPPS) such as pop-up hoods and windshield airbag in the vehicle. The study indicates how these systems are effective in reducing the fatalities in pedestrian accidents and how to evaluate the performance of these deployable systems. The pedestrian & VRU road fatalities contribute to more than 33percent of total road fatalities in India. Worldwide regulations for pedestrian protection include the evaluation of head injuries at a relative speed of
To determine causation and contributory factors of “looked-but-failed-to-see” (LBFTS) junction accidents in which the driver stated that “I did not see the pedestrian,” in-depth studies of 22 such accidents which had taken place in Hong Kong were conducted. The studied crashes were all video recorded by closed-circuit television (CCTV) cameras and/or dashboard cameras. Using the video recordings, these junction accidents were reconstructed at the scenes to determine the drivers’ views of the pedestrians and the sequence of events leading up to each accident. The results of the reconstructions and the police investigations, as well as the testimony of the drivers, were analyzed to identify causation and contributing factors of each accident. Attention error/visual search strategy (41%) and misjudgments of drivers (18%) remain the dominant cause of LBFTS crashes. However, it was found that eight crashes (36%) were attributed to the physical obstructions caused by the A-pillars of the
Avionics is a very restricting domain for obvious safety reasons. Along with miniaturization comes the idea of integration. More functionality on one spot requires a good management of privacy and congestion on shared platforms. This is why determinism is one of the keywords of avionics works. This led to protocols like ARINC653[1] assuring that multitask embedded programs respect a predictable policy applied by the operating system (OS). Another key protocol is ARINC664, which guarantees that multiple communicating systems efficiently share the network. These two protocols are pillars of the Integrated Modular Architecture (IMA) concept[2
The present study aims to investigate the effects of the several rear slant angles, φ = 25°, 30°, 32°, 33° and 35°, on the wake characteristics downstream of the Ahmed body because the angle of the rear window plays an important role in the flow characteristics. This work presents numerical simulations using ISIS-CFD flow solver which is developed by Centrale Nantes and CNRS. The turbulence model used is an hybrid RANS-LES model: the Improved Delayed Detached Eddy Simulation (IDDES). Detailed discussions of the flow features are provided using time-averaged streamlines, vorticity contours, turbulent kinetic energy contours and an iso-surface of l2. Drag and lift coefficients are also presented. In the symmetry plane, three critical flow points, which correspond to foci of separation and saddle point in the wake of the Ahmed body, and the focus of separation over the slanted surface are presented. When the slant angle increases, these critical points move near the Ahmed body before
This SAE Recommended Practice establishes boundaries for shade bands on glazed surfaces in class "A" vehicles. These boundaries are located so that the shade band can provide occupant comfort and driver vision protection from glare, with respect to solar radiation, under some lighting and driving conditions. Since shade bands transmit less visible light than adjacent glazed surfaces, the shade band boundaries establish boundaries for the driver's field of view
Conventional car manufacturing is extremely capital and energy-intensive. Due to these limitations, major auto manufacturers produce very similar, if not virtually identical, vehicles at very large volumes. This limits potential customization for different users and acts as a barrier to entry for new companies or production techniques. Better understanding of the barriers for low volume production and possible solutions with innovative production techniques is crucial for making low volume vehicles viable and accelerating the adoption of new production techniques and lightweight materials into the competitive marketplace. Additive manufacturing can enable innovative design with minimal capital investment in tooling and hence should be ideal for low and perhaps high volume parts. For this reason, it was desired to evaluate potential opportunities in manufacturing automotive parts with additive techniques. Analysis of traditional processes was first performed to identify and quantify
Flow visualization techniques are widely used in aerodynamics to investigate the surface trace pattern. In this experimental investigation, the surface flow pattern over the rear end of a full-scale passenger car is studied using tufts. The movement of the tufts is recorded with a DSLR still camera, which continuously takes pictures. A novel and efficient tuft image processing algorithm has been developed to extract the tuft orientations in each image. This allows the extraction of the mean tuft angle and other such statistics. From the extracted tuft angles, streamline plots are created to identify points of interest, such as saddle points as well as separation and reattachment lines. Furthermore, the information about the tuft orientation in each time step allows studying steady and unsteady flow phenomena. Hence, the tuft image processing algorithm provides more detailed information about the surface flow than the traditional tuft method. The main advantages over other flow
Individuals in the United States consume twice as much energy as those in any other region. Solitary workday commutes in light vehicles are the leading reason for this difference. An electric vehicle design is proposed to help catalyze more social, higher occupancy, commuting habits - through application of existing technology. Performance criteria are: 1) attract passengers to the suburban front yard at 6:30 AM, 2) match market leading crash test performance, cargo capability, and sense of freedom, and 3) deliver easier parking, better acoustics and better passenger mile efficiency. A vehicle as a rolling event venue determines a large windscreen, side-by-side upright seating arrangements, and acoustic excellence -an experience where there are only good seats. These requirements force a decision to close the wake along a vertical line to form a narrow wake. The chassis is platform batteries with dual motor electric rear drive and undetermined front drive. Findings: 1 Narrow wake
Items per page:
50
1 – 50 of 100