Browse Topic: Mountings

Items (923)
The stiffness and positioning of engine mounts are crucial in determining the powertrain rigid body modes and kinetic energy distribution. Therefore, optimizing these mounts is essential in the automotive industry to separate the torque roll axis (TRA) and minimize vibration. This study aims to enhance mount locations by isolating the engine rigid body modes and predicting the inter-component force (ICF) and transfer function of the vehicle. The individual ICFs for engine mountings are calculated by applying a unit force at the bearing location. Critical frequencies are identified where the amplification exceeds the unit force at the mounting interface between the engine and the frame. The transfer function approach is utilized to assess the vibration at the handlebar. Both ICF and transfer functions analyze the source and path characteristics linked to critical response frequencies. This understanding aids in enhancing mounting positions to minimize vibration levels, thereby enhancing
Jha, Niraj KumarYeezaku, Antony NeominVictor, Priyanka EstherKrishnamurthy, Govindasamy
In the fast growing automotive sector, reliability & durability are two terms of utmost importance along with weight and cost optimization. Therefore it is important to explore new technology which has less weight, low manufacturing cost and better strength. It also seek for a quick, cost effective and reliable methodology for its design validation so that any modification can be made by identifying the failures. This paper presents the rig level real world usage pattern simulation methodology to validate and correlate the vehicle level targets for micro strain, wheel forces and displacement on suspension components like optimized Z spring, torque rods, pan hard rod & mounting brackets of newly developed air suspension for buses
Tangade, Atul BanduBabar, SunilBankar, Milind AchyutraoMehendale, RavindraDhumal, KailasBhusari, DeepakSonawane, RavindraShinde, Saurabh
As “point of need” additive manufacturing emerges as a priority for the Department of Defense (DoD), Australian 3D printing provider SPEE3D is one of several companies demonstrating that its machines can rapidly produce castings, brackets, valves, mountings and other common replacement parts and devices that warfighters often need in an on-demand schedule when deployed near or directly within combat zones. DoD officials describe point of need manufacturing as a concept of operations where infantry and squadron have the equipment, machines, tools and processes to rapidly 3D print parts and devices that are being used in combat. Based in Melbourne, Australia, SPEE3D provides cold spray additive manufacturing (CSAM) machines that use a combination of robotics and high-speed kinetic energy to assemble and quickly bind metal together into 3D-printed parts without the need for specific environmental conditions or post-assembly cooling or temperature requirements. Over the last two years, the
ABSTRACT A 3D printed battery bracket is strengthened via post-print thermal annealing, demonstrating a transitionable approach for additive manufacturing of robust, high performance thermoplastic components. Citation: E. D. Wetzel, R. Dunn, L. J. Holmes, K. Hart, J. Park, and M. Ludkey, “Thermally Annealed, High Strength 3D Printed Thermoplastic Battery Bracket for M998,” In Proceedings of the Ground Vehicle Systems Engineering and Technology Symposium (GVSETS), NDIA, Novi, MI, Aug. 16-18, 2022
Wetzel, E. D.Dunn, R.Holmes, L. J.Shearrow, CaseyHart, K.Park, J.Ludkey, M.
ABSTRACT A detailed methodology employing a system model of a tracked vehicle with a gun turret is used to analyze the stresses and loads applied to the gun mount as a result of gun firing events. The vehicle system model combines a Virtual Lab.Motion model of the tracked vehicle and gun mount which includes track super element, flexible gun mount body, and a beam element representation of the gun and gun tube sleeve coupled with a MATLAB/Simulink model of the hydraulic/pneumatic recoil system and gun pointing control system. This coupled system model with flexible components is needed for this analysis to determine the portion of the impulse that results in gun mount deformation. A brief overview of the vehicle system model, a detailed description of the gun mount model, and analysis of the gun mount loads and stress is included
Youtt, Dan
The functionality of the Powertrain mount is to securely anchor the engine and gearbox within a vehicle, and effectively absorb vibrations, while simultaneously shielding the vehicle's body from powertrain movements and road irregularities. The mounts are supported by engine mount brackets, which serve as connectors between the engine mount and the vehicle's body-in-white (BIW), providing a structural link that secures the engine and gearbox assembly. Conventionally made with materials such as aluminum, sheet metal, or cast iron, a recent surge has been seen toward using a viable substitute in Fiber Reinforced Polymer (FRP). This transition is driven by the potential to reduce weight and cost, while also improving Noise, Vibration, and Harshness (NVH) characteristics. This study aimed to evaluate the relative strengths of existing brackets compared to those made of FRP, with a focus on their modal response and crash resistance. Due to the absence of a standardized method for modelling
Hazra, SandipKhan, Arkadip
A method of overall modeling and step-by-step solution was proposed to verify and analyze the strength of the mount shell. First, a reliable finite element simulation model was established based on testing of the mechanical properties of rubber materials, constitutive model construction, and stiffness tests of the mounts. Second, the displacement of the mount system under preloading and crash loads was calculated separately through the modeling of the powertrain mount simulation, which provided accurate load conditions of the mount for the following work. Finally, the strength calculation and evaluation of the mount shell was completed with the quasi-static solution method. This calculation method could consider the influence of complex factors comprehensively, such as assembly load distribution, large deformation of rubber, and contact nonlinearity on the stress distribution of the mount shell. In addition, the calculation method could solve the problem of balance between solution
Li, KeliangChen, GuozhengSun, WanyuYan, ShanhengLi, MingLiu, Baoguo
Automotive closure slam is the most crucial attribute affecting the closure structure and its mountings on BIW due to its high occurrence in real-world usage. Thus, virtual simulation of closure slam becomes necessary and is generally carried out using explicit codes with associated technical hitches like all-requisite inputs availability, FE modeling and analysis techniques, substantial human effort, high solution time, human and computational resource competence, or even access to suitable expensive explicit FE solver. Hence it becomes challenging to virtually analyze the design at every design phase of product development cycle under strict timelines leading to possibilities of both over- and under-designed parts, sometimes resulting in physical testing or even field failures. So, the need for an alternative simplified representation of closure slam, addressing the typical issues faced during explicit dynamic simulation and producing acceptable analysis outputs, gains significance
Chatterjee, Suprakash
Minimizing vibration transmitted from the exhaust system to the vehicle’s passenger compartment is the primary goal of this article. With the introduction of regulatory norms on NVH behavior and emissions targets, it has become necessary to address these issues scientifically. Stringent emissions regulations increased the complexity of the exhaust system resulting in increased size and weight. Exhaust system vibration attenuation is essential not only from the vehicle NVH aspects but also for the optimized functionality of the subsystems installed on it. Based on earlier studies, this work adopts a more thorough strategy to reduce vehicle vibration caused by the exhaust system by adjusting it to actual operating conditions. To achieve this, a complete vehicle model of 22 DOF is considered, which consists of a powertrain, exhaust system, chassis frame, and suspension system. A method for evaluating static and dynamic vibration response is proposed. Through the use of the vehicle’s rigid
Sarna, Amit KumarSingh, JitenderKumar, NavinSharma, Vikas
This recommended practice provides recommendations for minimizing high temperature oxidation (HTO) during the heat treatment of aluminum alloy products and parts. HTO leads to deterioration of properties
AMS D Nonferrous Alloys Committee
The underslung arrangement consists of a 500kVA (kilovolt amperes) diesel generator set mounted below a railway passenger coach. To meet stringent vibration requirement in passenger compartment, dual vibration isolation arrangement is proposed for underslung arrangement. Such type of arrangement provides a high degree of isolation from engine induced vibration. Performance of dual stage isolation depends on stiffness and mass ratio of genset mass to intermediate bracketry mass. High vibration excitations are observed on rail coach floor during testing of baseline design. These vibration levels are more than rail prescribed limits and passenger can easily feel these vibrations. Study of dual stage (2 degree of freedom) isolation system frequencies and transmissibility is performed. Root cause for existing system is assessed through vibration transmissibility analysis. Modal analysis was performed to understand mode shapes and interaction between the mounting structure and isolators
Kumar, MukeshJadhav, YogeshBhagat, Gokul V.Mahanta, BibhuKumar, Prashant B.
Fiber-reinforced plastics (FRPs), produced through injection molding, are increasingly preferred over steel in automotive applications due to their lightweight, moldability, and excellent physical properties. However, the expanding use of FRPs presents a critical challenge: deformation stability. The occurrence of warping significantly compromises the initial product quality due to challenges in part mounting and interference with surrounding parts. Consequently, mitigating warpage in FRP-based injection parts is paramount for achieving high-quality parts. In this study, we present a holistic approach to address warpage in injection-molded parts using FRP. We employed a systematic Design of Experiments (DOE) methodology to optimize materials, processes, and equipment, with a focus on reducing warpage, particularly for the exterior part. First, we optimized material using a mixture design in DOE, emphasizing reinforcements favorable for warpage mitigation. After careful consideration of
Seo, Kyeong-BaePark, Sang SunLee, ChoonSoo
Rubber mount as an important element can reduce the vibration transmitted by the engine to the frame. And under small and medium deformation conditions, Mooney-Rivlin model can well describe the mechanical properties of the rubber mount. The accurate parameters of Mooney-Rivlin model are the basis of describing the mechanical properties of the mount. First, taking powertrain rubber mount as the research object, the influence of preload on the static characteristics of the mount is studied by the preload test rig. Second, Particle swarm optimization-Back propagation neural network (PSO-BPNN) model and Back propagation neural network (BPNN) model was established. After the number and step length of hidden layer neurons were determined, the prediction accuracy of the two models is compared. Then, combined with finite element analysis and crow search algorithm, a parameter identification model considering preload is established, the constitutive parameters corresponding to preload and non
Sun, JiaweiZhao, RenfeiSun, HongjieMa, Qiang
Electric motor noise mitigation is a challenge in electric vehicles (EVs) due to the lack of engine masking noise. The design of the electric motor mounting configuration to the motor housing has significant impacts on the radiated noise of the drive unit. The stator can be bolted or interference-fit with the housing. A bolted stator creates motor whine and vibration excited by the motor torque ripple at certain torsional resonance frequencies. A stator with interference fit configuration stiffens the motor housing and pushes resonances to a higher frequency range, where masking noise levels are higher at faster vehicle speeds. However, this comes with additional cost and manufacturing process and may impact motor efficiency due to high stress on stators. In this paper, a thin sheet metal NVH ring is developed as a tunable stiffness device between the stator and the motor housing. It is pre-compressed and provides additional torsional rigidity to mitigate torsional excitations. A CAE
He, SongTran, XuanNaismith, GregoryDu, IsaacPatruni, Pavan KumarBaladhandapani, Dhanasekar
In-cabin Noise at low frequency (due to engine or road excitation) is a major issue for NVH engineers. Usually, noise transfer function (NTF) analysis is carried out, due to absence of accurate actual loads for sound pressure level (SPL) analysis. But NTF analysis comes with the challenge of having too many paths (~20 trimmed body attachment locations: engine and suspension mounts, along with 3 directions for each) to work on, which is cumbersome. Physical test transfer path analysis (TPA) is a process of root cause analysis, by which critical contributing paths can be obtained for a problem peak frequency. In addition to that, loads at the attachment points of trimmed body of test vehicle can be derived. Both these outputs are conventionally used in CAE analysis to work on either NTF or SPL. The drawback of this conventional approach is that the critical bands and paths suggested are based on the problem peak frequency of test vehicle which may be different in CAE. Secondly, the force
Pimpalkhare, NinadMochizuki, Shinei
To enhance the transient vibration performance of the vehicle at key on and key off, a method for optimizing mount parameters of a powertrain mounting system (PMS) is proposed. Uncertainties of mount parameters widely exist in a PMS, so a method for optimizing mount parameters of a PMS, which treats the mount parameters of a PMS as uncertain, is also proposed in this paper. Firstly, a 13 degrees of freedom (DOFs) model including car body with 3 DOFs, a PMS with 6 DOFs and unsprung mass with 4 DOFs is established, and the acceleration of the active side of mounts is calculated. An experiment is carried out to measure the accelerations located at active and passive sides of each mount and the accelerations of seat track. A comparison is made between the measured and estimated accelerations, and the proposed model is validated. Two optimization methods for the PMS are proposed based on the developed 13 DOFs model. One method treats mount parameters as deterministic variables, while
Lin, ShuoYin, Zhi-HongJiang, Yong-FengSong, Yan-PingShangguan, Wen-Bin
Plastic design is one of the upcoming fields of interest when it comes to weight optimization, sustainability, strength, and overall aesthetics of an automobile. What is often ignored is the amount of flexibility a plastic designer has, of integrating and packaging various components of an automobile into a single part and still make it an integral part of its complex aesthetics. This paper highlights upon one such part that is being developed: An integrated bracket which packages ADAS camera, Rain Light Sensor, and an Auto-dimming IRVM. Apart from packaging the mentioned components, this bracket also has mounting provisions for an aesthetic cover (also referred to as beauty cover). The objective of this paper is to highlight the importance of integration of several parts into a single part for packaging multiple components that need to be placed in a close proximity with each other. This paper includes the demonstration of old design which consisted of multiple parts along with how we
Chandravanshi, PriyanshParthiban, MohanBable, ShubhamDharmatti, Girish
In this study, an optimized structure for opening the headlining considering the deployment of the face-to-face roof airbag was studied. It was confirmed that the deployment performance differs depending on the skin of the headlining, and a standardized structure with mass production was proposed. Non-woven fabric and Tricot skin, which are economical and high-end specifications, satisfy the performance of PVC fusion application specifications after cutting 80% of the skin. The structure that satisfies the entire body including the knit specifications is a type that separates the roof airbag area piece, the corresponding soft piece is separated, and the deployment performance is satisfied with safety. Therefore, the structure is proposed as a standardized structure. This structure is expected to be applicable to roof DAB (Driver Airbag), PAB (Passenger Airbag), and Sunroof Airbag, which will be necessary technologies to secure indoor space. Regardless of which area the airbag will be
Park, Jiseob
Side doors are pivotal components of any vehicle, not only for their aesthetic and safety aspects but also due to their direct interaction with customers. Therefore, ensuring good structural performance of side doors is crucial, especially under various loading conditions during vehicle use. Among the vital performance criteria for door design, torsional stiffness plays an important role in ensuring an adequate life cycle of door. This paper focuses on investigating the impact of several door structural parameters on the torsional stiffness of side doors. These parameters include the positioning of the latch, the number of door side hinge mounting points on doors (single or double bolt), and the design of door inner panel with or without Tailor Welded Blank (TWB) construction. The findings of this study reveal that the change in latch position has the most significant influence on torsional stiffness, followed by the removal of TWB from the inner panel, upon implementation of suitable
Goyal, Vinay KumarSelvan, VeeraPandurangan, VenugopalUnadkat, SiddharthAlmeida, Neil Ricardo
The recent surge in platforms like YouTube has facilitated greater access to information for consumers, and vehicles are no exception, so consumers are increasingly demanding of the quality of their vehicles. By the way, the door is composed of glass, moldings, and other parts that consumers can touch directly, and because it is a moving part, many quality issues arise. In particular, the door panel is assembled from all of the above-mentioned parts and thereby necessitates a robust structure. Therefore, this study focuses on the structural stiffness of the door inner panel module mounting area because the door module is closely to the glass raising and lowering, which is intrinsically linked to various quality issues
Cho, KyeongkukChoi, JEWON
NVH refinement of commercial vehicles is the key attribute for customer acceptance. Engine and road irregularities are the two major factors responsible for the same. During powertrain isolators’ design alone, the mass and inertia of the powertrain are usually considered, but in practical scenarios, a directly coupled subsystem also disturbs the boundary conditions for design. Due to the upgradation in emission norms, the exhaust aftertreatment system of modern automotive vehicles becomes heavier and more complex. This system is further coupled to the powertrain through a flexible joint or fixed joint, which results in the disturbance of the performance of the isolators. Therefore, to address this, the isolators design study is done by considering a multi-body dynamics model of vehicles with 16 DOF and 22 DOF problems, which is capable to simulate static and dynamic real-life events of vehicles. Design indicators are thoroughly analyzed and validated through the rigid body modes and
Sarna, Amit KumarSingh, JitenderKumar, NavinSharma, Vikas
Most motor mounts, even for EV applications, are made of metal alloys. It makes intuitive sense: It's a vibration-intensive mounting application that demands durability that matches the life of the vehicle itself. But there is another way. Now, a composite nylon-based motor mount on the Cadillac Lyriq has won the Society for Automotive Analysts' Innovation in Lightweighting Award. The mount is a collaboration between GM, anti-vibration parts maker DN Automotive and chemical company Celanese. It is made with Zytel PA NVH Gen 2, a new polyamide (PA 66). The results not only showed up in development data, but in the end product, which has reviewers raving about how quiet the Lyriq's cabin is - “crypt quiet,” according to Automotive News
Clonts, Chris
In comparison to traditional gasoline-powered vehicles, Electric vehicles (EVs) development and adoption is driven by several factors such as zero emissions, higher performance, cost effective in maintenance, smoother and quieter ride. Global OEMs are competing to provide a reduced in-cab noise for ensuring a smooth and quiet driving experience. Short project timelines for EV demands quick design and development. In initial stages of project, input data availability of EV is limited and a simplified approach is necessary to accelerate the development of vehicle. This paper focuses on simulation methodology for predicting structure borne noise from powertrain deploying Transfer Path Analysis approach. Current simulation methodology involves full vehicle model with multiple flexible bodies and full BIW flexible model which leads to complex modelling and longer simulation times. The proposed transfer path analysis technique utilises, a simplified Multibody Dynamics EV powertrain mount
Duraikannu, DineshIqbal, Shoaib
Usually conventional iterative methods of optimization will consume more time to optimize the given design. Mostly, it becomes very difficult if multiple loads are acting on the structure contradicting each other. CAE based optimization technique becomes more useful in such cases to optimize the given design and achieve weight reduction. Optimization methods offers guidance to expedite solutions, resulting in a substantial reduction in product development time. Nowadays, optimization became inevitable part among the virtual validation processes of design in industries. A wide range of optimization methods have been effectively employed in the design of tractor components, especially mounting brackets, chassis and skid housing for the development of off-road vehicle. Based on the design stage, various optimization techniques were followed i.e. Topology, size and shape. Depending upon the available analysis time & Design freedom, determines the type of optimization approach to be used
Dumpa, Mahendra ReddyPerumal, SolairajRedkar, DineshPagare, NitinSubbaiyan, Prasanna BalajiMani, Suresh
With the advancement of regulatory norms in automobile industry, there is a challenge to meet performance efficiency targets, especially with a lightweight platform, while providing superior driving experience to customers. The shift towards weight optimization, makes the vehicle structure more susceptible to transfer a diverse range of noise and vibrations through body. Although most undesirable noises perceived inside the cabin can be reduced by superior technology engine mounts and NVH packaging, all such solutions lead to cost addition. Intelligent considerations in part design can be used to supplement predictable transfer paths to quell the unwanted vibrations. One such case is of the gear whine noise in certain rpm bands caused by inherent gear meshing frequency coinciding with natural frequency of an engine mounting bracket. This paper demonstrates two methodologies to counter such a phenomenon, either through engine mount bracket natural frequency optimization or addition of a
Ghosh, ChiranjitAgrawal, AdheeshKarmakar, SudiptoSrivastava, ShubhamKhan, Aamir
With the rise of worldwide trends towards light weighting and the move towards electric vehicles, it is now more important than ever for the automotive industry to develop and implement lightweight materials that will result in significant weight reduction and product improvements. A great deal of research has been done on how to best combine and configure honeycomb cores with the right face sheets for Truck-Mounted Container Applications. Honeycomb structures possess the ability to bring about superior structural rigidity when the core parameters are selected and optimized based on the automotive application requirements. Through a variety of experimental tests for various combinations of the core parameters, the selection of the critical honeycomb core parameters to efficiently increase the compressive strength and panel rigidity of the entire container assembly has been evaluated and compared in order to determine the most effective combination to produce superior results for
Phukan, PrernaDave, Rajeev
This case study involves the failure analysis of the wheel arch structure for a commercial truck. The wheel arch is an important vehicle trim aggregate from both the regulatory perspective (spray suppression) as well as from the aesthetics of the truck. But, the durability of this part is affected by the vehicle architecture, vehicle load capacity as well as the operating conditions. This is more critical due to the nature of the overhang experienced by the mounting bracket assemblies that hold these wheel arches/mud flaps. This generally consist of tubular and sheet metal welded structures bolted on to the main chassis long members. These failures were observed in a legacy vehicle, where very little details of the complete vehicle digital simulation and testing performance were readily available. This paper deals with the identification of the root cause of the failure simulation of the root cause in CAE improvement in design CAE evaluation of improved design Correlation of the
Venkatesh, Srinivasa
Globally all OEMs are moving towards electric vehicle to reduce emission and fuel cost. Customers expect highest level of refinement and sophistication in electric vehicle. At present, the customers are sensitive to high pitched tonal noise produced by electric powertrain which gives a lot of challenges to NVH engineers to arrive at a cost-effective solution in less span of time. Higher structure borne tonal noise is perceived in electric vehicle at the vehicle speeds of ~ 28 kmph, 45 kmph and 85 kmph. The test vehicle is front wheel drive compact SUV powered by motor in the front. The electric drive unit is connected to cradle and subframe with help of three mounts. Transfer path analysis (TPA) using blocked forces method is carried out to identify the exact forces of the electric drive unit entering the mounts. Powertrain mount is characterized by applying the predicted forces and dynamic stiffness at problematic frequency is measured. By reducing the dynamic stiffness of powertrain
S, Nataraja MoorthyRao, ManchiRaghavendran, PrasathSelvam, Ebinezer
During validation of a new brake lining on a light duty truck application, the brake rotor exhibited high lateral runout on the friction surfaces. As the engineering team investigated the issue more carefully, they noticed the rotor lateral runout was also changing from revolution to revolution. The team ran testing on multiple light pickup vehicles and found differences in the amount of rotor runout variation. The rotor lateral runout and runout variation can cause vibration and pulsation of the passenger seat and the steering wheel. To identify the root cause of the high level of rotor lateral runout and runout variation, measurement data was collected and analyzed from the vehicle level test. During further analysis, some of the runout variation corresponded to a wheel bearing internal frequency. The bearing internal geometry was studied to confirm what factors affected the runout variation. The team also conducted testing to see how the mating components may have affected the wheel
Hwang, HyungdooKuehl, PaulSutherlin, RobertGrubaugh, Kelly
The main purpose of the powertrain mounting system is to reduce excessive motion created by the powertrain system as well as to isolate vibration and noise from being transferred to the main system There are two fundamental requirements which needs to be fulfilled by mounting system, those are static requirement and dynamic requirement. Where the static requirements states that it should support the whole weight of the powertrain system under sever driving conditions and to avoid the metal-to-metal contact between oscillating parts of engine and structure. Dynamic requirement states that it should efficiently isolate the vibration and unbalanced forces, furthermore it should allow the sufficient movement of powertrain so as it will not damage the structure of the chassis. The mounting system also plays a significant role in vehicle ride and handling, as it controls the motion of largest mass of the vehicle i.e., powertrain. Therefore, a great attention is being given to the analysis
Ghale, GuruprasadThakur, Pragyesh SinghTHAKUR, SUNILWagh, Sachin
The design method for the powertrain mounting system in internal combustion engine vehicles is well-established. Electric vehicles experience higher vibration frequencies and more significant transient responses when accelerating or braking than fuel vehicles due to their high speed and fast response. Therefore, the design of the electric drive assembly mounting system requires further development. The modeling of electric drive assembly mounting systems often neglects the mounting bracket’s influence, which significantly affects the center of mass and rotational inertia of the electric drive assembly. This paper examines the effect of the mounting bracket in the electric drive assembly mounting system. It establishes a mathematical model with six degrees of freedom for the mounting system, considering the mounting bracket. By comparing the natural characteristics and the transient response, it is discussed whether the mass of the mounting bracket greatly influences the system. Further
Zhang, LijunWang, YifanMeng, DejianLiu, DengchengZhou, Xiao Ming
Vehicle vibration is the key consideration in the early stage of vehicle development. The most dynamic system in a vehicle is the powertrain system, which is a source of various frequency vibration inputs to the vehicle. Mostly for powertrain mounting system design, only the uncoupled powertrain system is considered. However, in real situations, other subsystems are also attached to the powertrain unit. Thereby, assuming only the powertrain unit ignores the dynamic interactions among the powertrain and other systems. To address this shortcoming, a coupled powertrain and driveline mounting system problem is formulated and examined. This 16 DOF problem is constructed around a case of a front engine-based powertrain unit attached to the driveline system, which as an assembly resting on other systems such as chassis, suspensions, axles, and tires. First, the effect of a driveline on torque roll axis and other rigid body modes decoupling is examined analytically in terms of eigensolutions
Singh, JitenderSarna, Amit KumarKumar, NavinSharma, Vikas
U.S. military service members are provided protective head gear for use in training and operational environments. This headgear is typically in the form of a helmet, at a minimum consisting of a rigid outer shell and an individual fitting and retention system, which is an essential personal protective equipment (PPE) item. Many different helmet configurations are used by the U.S. soldier, depending on their military occupational series, the anticipated threat, and the operational environment
This procedure is applicable to modes from 500 and 13,000 Hz. The parameters measured with this procedure are defined as the damping factor, ξ for first nine vibration modes of the beam. The measurement will be done in free-free conditions and with temperature
Brake NVH Standards Committee
AS95234 includes reverse bayonet coupling, high current electrical connectors that are watertight and principally used in shipboard, ground vehicles and ground support equipment applications at serve voltages from 200 to 3000 Vrms and temperatures between -55 °C and +125 °C (-67 °F and +257 °F). See 6.1.5 for applications details. For aerospace application connectors, refer to AS50881
AE-8C1 Connectors Committee
This SAE Recommended Practice includes wheel mounting elements subject to standardization in a series of industrial and agricultural disc wheels. The disc may be reversible or nonreversible and concave or convex. (See Figure 1 and Table 1
MTC8, Tire and Rim
This SAE Recommended Practice establishes uniform Installation Parameters for desiccant Air Dryers for vehicles with compressed air systems
Truck and Bus Brake Supply and Control Components Committee
This user’s manual covers the small adult female Hybrid III test dummy. It is intended for technicians who work with this device. It covers the construction and clothing, disassembly and reassembly, available instrumentation, external dimensions and segment masses, as well as certification and inspection test procedures. It includes instructions for safe handling of the instrumented dummy, repairing dummy flesh, and adjusting the joints throughout the dummy
Dummy Testing and Equipment Committee
This recommended practice contains dimensions and tolerances for outboard mounted brake drums and disc wheel hubs in the interface areas. This recommended practice is intended for outboard mounted brake drums and disc wheel hubs commonly used on class 7 and 8 commercial vehicles. Included are SAE J694 mounting systems II, III, IV, XIV, and X. Special and less common applications are not covered
Truck and Bus Wheel Committee
These methods of test are applicable for determining the resistance to snagging and abrasion of automotive bodycloth, vinyl, and leather
Textile and Flexible Plastics Committee
In the mounting of vibration sources and receivers, it is typically desirable to have low stiffness for isolation. On the other hand, durability may demand a high stiffness to handle large inputs without excessive motion, which seems like a contradictory requirement. Both may be achieved using nonlinear stiffness mounts which make use of elastomer deformation to exhibit softening through geometric nonlinearity. This paper discusses a physical proof of concept for a quasi-zero stiffness mount design with a three-regime stiffness curve including a preload, isolation, and motion control regions. Building on a design concept proposed in prior literature, new experimental validation is obtained for the prior nonlinear static stiffness property, which is then fit into a more stable mount topology. Fabrication and material issues are also discussed. Finite element models are used with material coupon tests to characterize the elastic properties of chosen materials, as well as predicting the
Gusmano, PaulFredette, Luke
Items per page:
1 – 50 of 923