Browse Topic: Frames

Items (1,446)
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
ABSTRACT A time-accurate multibody dynamics model of the suspension system of a tracked vehicle is experimentally validated using a full-scale tracked-vehicle on an N-post motion simulator. The experiments consist of harmonic excitations at various amplitudes and frequencies and ramp excitations of the vehicle road-wheels (without the track), with each road wheel under one linear actuator of the N-post motion simulator. A high-fidelity multibody dynamics model of the vehicle along with the N-post motion simulator is constructed. The multibody dynamics model consists of rigid bodies, joints, rotational springs (that include non-linear rotational stiffness, damping and friction), actuators and contact surfaces. The rigid bodies rotational equations of motion are written in a body-fixed frame with the total rigid-body rotation matrix updated each time step using incremental rotations. Connection points on the rigid bodies are used to define joints between the bodies including revolute
Wasfy, Tamer M.O’Kins, JamesRyan, David
ABSTRACT Automatic guided vehicles (AGV) have made big inroads in the automation of assembly plants and warehouse operations. There are thousands of AGV units in operation at OEM supplier and service facilities worldwide in virtually every major manufacturing and distribution sector. Although today’s AGV systems can be reconfigured and adapted to meet changes in operation and need, their adaptability is often limited because of inadequacies in current systems. This paper describes a wireless navigated (WN) omni-directional (OD) autonomous guided vehicle (AGV) that incorporates three technical innovations that address the shortfalls. The AGV features consist of: 1) A newly developed integrated wireless navigation technology to allow rapid rerouting of navigation pathways; 2) Omnidirectional wheels to move independently in different directions; 3) Modular space frame construction to conveniently resize and reshape the AGV platform. It includes an overview of the AGVs technical features
Cheok, Ka CRadovnikovich, MichoFleck, PaulHallenbeck, KevinGrzebyk, SteveVanneste, JerryLudwig, WolfgangGarner, Robert
ABSTRACT At the request of the US Army’s Tank Automotive Command (TACOM) a device was built to measure the suspension parameters of any military wheeled vehicle. This is part of an ongoing effort to model and predict vehicle dynamic behavior. The new machine is called the Suspension Parameter Identification and Evaluation Rig (SPIdER) and has a capacity intended to cover all of the military’s wheeled vehicles. The machine operates by holding the vehicle body nominally fixed while hydraulic cylinders move an “axle frame” in bounce or roll under each axle being tested. Up to two axles may be tested at once. Forces at the tires and motions of the wheel centers in three dimensions and two angles are measured. Other motions of the suspension and the minimal motions of the vehicle body are measured. For steer axles the steering ratio, Ackerman steer characteristics, and kingpin orientation are measured
Andreatta, DaleHeydinger, GarySidhu, AnmolBixel, RonaldKurec, AleksanderSingh, AmandeepBaseski, IgorSkorupa, Thomas
Abstract RedRAVEN is a pioneered autonomous robot utilizing the innovative Linked-Bogie dynamic frame, which minimizes platform tilt and movement, and improves traction while maintaining all the vehicle’s wheels in contact with uneven surfaces at all times. Its unique platform design makes the robot extremely maneuverable since it allows the vehicle’s horizontal center of gravity to line up with the center of its differential-drive axle. Where conventional differential-drive vehicles use one or more caster wheels either in front or in the rear of the driving axle to balance the vehicle’s platform, the Linked-Bogie design utilizes caster wheels both in the front and in the rear of the driving axle. Without using any springs or shock absorbers, the dynamic frame allows for compensation of uneven surfaces by allowing each wheel to move independently. The compact and lightweight ground vehicle also features a driving-wheel neutralizing mechanism, a rigid aluminum frame, and a translucent
Mekhtarian, AraHorvath, JosephLin, C.T.
ABSTRACT Since the development of combat vehicles for military use, such as tanks, infantry carriers, gun transports, etc. the main approach has been a monolithic structure that has been described as monocoque. This approach has been the standard–bearer since the inception of modern combat vehicles. Since the end of the Cold War, the world has become a much more “Multi–Polar” world. The U.S. is not locked in a static, monotonic engagement against the Soviet Union and its allies. The nature of the threat has changed. The U.S. Army is looking to make its Combat Vehicle fleet lighter and more adaptable to new technology and changing environments. By doing so the U.S. will be better able to project forces where they are needed. Lighter weight means more flexibility in transportation of equipment to various locations. In addition, the U.S. Army will be better able to deploy forces that have the latest and/or the most desirable protection required for the specific engagement they may
Hodges, ScottOstberg, Donald
In recent years, autonomous vehicles (AVs) have been receiving increasing attention from investors, automakers, and academia due to the envisioned potentials of AVs in enhancing safety, reducing emissions, and improving comfort. The crucial task in AV development boils down to perception and navigation. The research is underway, in both academia and industry, to improve AV’s perception and navigation and reduce the underlying computation and costs. This article proposes a model predictive control (MPC)-based local path-planning method in the Cartesian framework to overcome the long computation time and lack of smoothness of the Frenet method. A new equation is proposed in the MPC cost function to improve the safety in path planning. In this regard, an AV is built based on a 2015 Nissan Leaf S by modifying the drive-by-wire function and installing environment perception sensors and computation units. The custom-made AV then collected data in Norman, Oklahoma, and assisted in the
Arjmandzadeh, ZibaAbbasi, Mohammad HosseinWang, HanchenZhang, JiangfengXu , Bin
Squeak and rattle (SAR) noise audible inside a passenger car causes the product quality perceived by the customer to deteriorate. The consequences are high warranty costs and a loss in brand reputation for the vehicle manufacturer in the long run. Therefore, SAR noise must be prevented. This research shows the application and experimental validation of a novel method to predict SAR noise on an actual vehicle interior component. The method is based on non-linear theories in the frequency domain. It uses the Harmonic Balance Method (HBM) in combination with the Alternating Frequency/Time Domain Method (AFT) to solve the governing dynamic equations. The simulation approach is part of a process for SAR noise prediction in vehicle interior development presented herein. In the first step, a state-of-the-art linear frequency-domain simulation estimates an empirical risk index for SAR noise emission. Critical spots prone to SAR noise generation are located and ranked. In the second step, the
Rauter, AndreasUtzig, LukasWeisheit, KonradMarburg, Steffen
Design verification and quality control of automotive components require the analysis of the source location of ultra-short sound events, for instance the engaging event of an electromechanical clutch or the clicking noise of the aluminium frame of a passenger car seat under vibration. State-of-the-art acoustic cameras allow for a frame rate of about 100 acoustic images per second. Considering that most of the sound events introduced above can be far less than 10ms, an acoustic image generated at this rate resembles an hard-to-interpret overlay of multiple sources on the structure under test along with reflections from the surrounding test environment. This contribution introduces a novel method for visualizing impulse-like sound emissions from automotive components at 10x the frame rate of traditional acoustic cameras. A time resolution of less than 1ms eventually allows for the true localization of the initial and subsequent sound events as well as a clear separation of direct from
Rittenschober, ThomasKarrer, Rafael
REE Automotive is aiming to be a major disruptor in the medium-duty truck space with the rollout of its P7 EV chassis. The P7 frame is built around its “REEcorners” suspension, which are modular suspension units featuring REE's x-by-wire design. By packaging components into the area between the chassis and the wheel, REE claims that it was able to design the P7 with a completely flat chassis with up to 35% more interior volume for passengers, cargo and batteries. “The REEcorners suspension system is the core of the technology that we built this truck around,” Peter Dow, VP of engineering for REE Automotive, said during an interview with Truck & Off-Highway Engineering. “It also allows us to achieve the level of vehicle dynamics we were looking for. We were trying to make a truck that was very exciting and easy to drive
Wolfe, Matt
The present study introduces a novel approach for achieving path tracking of an unmanned bicycle in its local body-fixed coordinate frame. A bicycle is generally recognized as a multibody system consisting of four distinct rigid bodies, namely the front wheel, the front fork, the body frame, and the rear wheel. In contrast to most previous studies, the relationship between a tire and the road is now considered in terms of tire forces rather than nonholonomic constraints. The body frame has six degrees of freedom, while the rear wheel and front fork each have one degree of freedom relative to the body frame. The front wheel exhibits a single degree of freedom relative to the front fork. A bicycle has a total of nine degrees of freedom. The expression of the kinetic energy of a bike is formulated using quasi-coordinates in the local body-fixed coordinate frame, which provides a more simplified representation compared to the utilization of absolute coordinates in the global coordinate
Cheng, KaizhuoDuan, YupengWu, JinglaiZhang, Yunqing
An experiment is carried out to measure creep groan of a drum brake located in a trailer axle of a truck. The noise nearby the drum brake and accelerations on brake shoes, axle and trailer frame are collected to analyze the occurring conditions and characteristics of the creep groan. A multi-body dynamics model with 1/4 trailer chassis structures is established for analyzing brake component vibrations that generates the creep groan. In the model, the contact force between brake cam and brake shoes, the contact friction characteristics between brake linings and inner circular surface of brake drum, and the properties of chassis structure are included. Dynamic responses of brake shoes, axle and trailer frame during the braking process are estimated using the established model and the responses are compared with the measured results, which validate the model. Three conclusions of measurement and calculation are obtained. (1) The creep groan is usually generated when braking speed is lower
Zheng, Jing-YuanShangguan, Wen-BinTang, HaoLan, Wen-biao
This paper analyzes the mechanism of vibrational energy propagation and panel vibration generation at the point joints between frame and panel which can be applied to reduce the vehicle interior noise. In this study, we focused on the traveling wave in the early stage of propagation before the mode is formed and investigated the mechanism of panel vibration generation due to wave energy propagation and its reduction method. First, we show theoretically that the out-of-plane component of the transmitted power at the point joint between frame and panel that contributes to panel vibration is associated with frame deformation. Then, we show through numerical verification that panel vibration can be reduced by reducing the transmitted power of the out-of-plane component and explain the effectiveness of the frame-to-panel joint design guidelines based on energy propagation analysis. Next, this analysis method was applied to the vehicle body FEM model. Assuming road noise, an energy
Abe, KeisukeTanaka, YunosukeYamazaki, Toru
For the design optimization of the electric bus body frame orienting frontal crash, considering the uncertainties that may affect the crashworthiness performance, a robust optimization scheme considering tolerance design is proposed, which maps the acceptable variations in objectives and feasibility into the parameter space, allowing for the analysis of robustness. Two contribution analysis methods, namely the entropy weight and TOPSIS method, along with the grey correlation calculations method, are adopted to screen all the design variables. Fifteen shape design variables with a relatively high impact are chosen for design optimization. A symmetric tolerance and interval model is used to depict the uncertainty associated with the 15 shape design variables of key components in the bus body frame to form an uncertainty optimization problem in the form of an interval, and a triple-objective robust optimization model is developed to optimize the shape design variables and tolerances
Yang, XiujianLiu, Beizhen
A road test on semi-trailers is carried out, and accelerations of some characteristic points on the braking system,axles,and truck body is measured,also brake pressure and noise around the support frame is acquired.The measured data was analyzed to determine the causes of the brake noise, and the mechanism of the noise of the drum brake of semi-trailers during low-speed braking was investigated. The following conclusions are obtained: (1) Brake noise of the drum brake of the semi-trailer at low-frequency is generated from vibrations of the brake shoes, axle, and body, and the vibration frequency is close to 2nd natural frequency of the axle. (2) Brake noise is generated from stick-slip motion between the brake shoes and the brake drum, where the relative motion between the brake drum and the brake shoes is changed alternately with sliding and sticking, resulting in sudden changes in acceleration and shock vibration. A multi-body dynamic model of the semi-trailer is established for
Tang, HaoShangguan, Wen-BinKang, YingziZheng, Jing-YuanLan, Wen-Biao
Mechanical drawing plays an important role in managing, designing and implementing engineering projects, especially in the field of the automotive industry. The need for accuracy in element design and manufacturing is greater now than ever before in engineering industries. In order to increase accuracy, the part design and function must be clearly communicated between the design engineer and the manufacturing technicians, especially in automotive industry and feeder industries projects. Geometric Dimensions and Tolerances (GD&T) system of elements determines the quality, importance and price of the designed product. The standard used in the United States to define GD&T methodology is ASME Y14.5-2009 while the standard used in Europe is ISO 1101-2017. This article discussed the importance of using GD&T system including the types of geometrical features, limitations and accuracy, datum references frame and feature control frame to handle these symbols seamlessly. Moreover, the paper
Ali, Amr S.H.R.Ali, Akram M. S.Amin, Youssef W.R.Ali, Salah H. R.
The new idea discussed in this paper pertains to the carrier mechanism for spare wheels in heavy commercial vehicles. Typically, these vehicles are equipped with a spare wheel carrier featuring a rope mechanism for loading and unloading the spare wheel. The conventional placement of this system is on the side of the frame/chassis or within the limits of the side member. However, the tire-changing process in this system is often arduous, time-consuming, and requires significant effort. The proposed invention addresses these challenges by repositioning the spare wheel to a vertical orientation, facilitating easier access to its bolts and simplifying the removal process from the mountings. Furthermore, the innovation incorporates a three-way actuation system (Air Actuated, Electric motor-driven, or Hydraulic cylinder actuated mechanisms), thereby reducing the need for manual effort and enhancing driver comfort. The advantages of this invention over traditional carrier mechanisms include
Bonde, DevendraUpkare, Piyush PradipVerma, Rubal
Catalytic converters have been considered as an integral part of the vehicle powertrain for over a decade now, their application along with the engines increased significantly with the constant evolution of emission standards. Recent regulations keep a strict control on the major four pollutants of engine exhaust gas, i.e., Carbon Monoxide (CO), Nitrogen Oxides (NOx), Hydrocarbons (HC) & Particulate Matter (PM), which demands a highly efficient aftertreatment system. Efforts are continuously being made to downsize the engine for better fuel economy and low emissions, this puts additional requirement of designing a compact aftertreatment system equipped with Diesel Oxidation Catalyst (DOC), Diesel Particulate Filter (DPF) and Selective Catalytic Reduction (SCR). Compact catalytic converters experience larger vibration force transferred from the vehicle and hence the durability of the product is significantly impacted. Vibration sources are a) Engine, b) Road Load, using a long flex pipe
Gupta, BipinLi, JiangongSingaravel, Vinothkumar
This paper addresses the issues of long-term signal loss in localization and cumulative drift in SLAM-based online mapping and localization in autonomous valet parking scenarios. A GPS, INS, and SLAM fusion localization framework is proposed, enabling centimeter-level localization with wide scene adaptability at multiple scales. The framework leverages the coupling of LiDAR and Inertial Measurement Unit (IMU) to create a point cloud map within the parking environment. The IMU pre-integration information is used to provide rough pose estimation for point cloud frames, and distortion correction, line and plane feature extraction are performed for pose estimation. The map is optimized and aligned with a global coordinate system during the mapping process, while a visual Bag-of-Words model is built to remove dynamic features. The fusion of prior map knowledge and various sensors is employed for in-scene localization, where a GPS-fusion Bag-of-Words model is used for vehicle pose
Chen, GuoyingWang, ZiangGao, ZhengYao, JunWang, Xinyu
The current automotive industry has a growing demand for real-time transmission to support reliable communication and for key technologies. The Time-Sensitive Networking (TSN) working group introduced standards for reliable communication in time-critical systems, including shaping mechanisms for bounded transmission latency. Among these shaping mechanisms, Cyclic Queuing and Forwarding (CQF) and frame preemption provide deterministic guarantees for frame transmission. However, despite some current studies on the performance analysis of CQF and frame preemption, they also need to consider the potential effects of their combined usage on frame transmission. Furthermore, there is a need for more research that addresses the impact of parameter configuration on frame transmission under different situations and shaping mechanisms, especially in the case of mechanism combination. Firstly, this paper comprehensively reviews the schedulability analysis of the combined usage of CQF and frame
Luo, FengWang, ZitongRen, YiWu, MingzhiZhang, Xiaoxian
SLAM (Simultaneous Localization and Mapping) plays a key role in autonomous driving. Recently, 4D Radar has attracted widespread attention because it breaks through the limitations of 3D millimeter wave radar and can simultaneously detect the distance, velocity, horizontal azimuth and elevation azimuth of the target with high resolution. However, there are few studies on 4D Radar in SLAM. In this paper, RI-FGO, a 4D Radar-Inertial SLAM method based on Factor Graph Optimization, is proposed. The RANSAC (Random Sample Consensus) method is used to eliminate the dynamic obstacle points from a single scan, and the ego-motion velocity is estimated from the static point cloud. A 4D Radar velocity factor is constructed in GTSAM to receive the estimated velocity in a single scan as a measurement and directly integrated into the factor graph. The 4D Radar point clouds of consecutive frames are matched as the odometry factor. A modified scan context method, which is more suitable for 4D Radar’s
Zihang, HeXiong, LuZhuo, GuirongGAO, LetianLu, ShouyiZhu, JiaqiLeng, Bo
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
Kim, Jin HongLee, Dong KiKim, Gyu SikJang, Gang-WonKim, Han Kil
Tradespace exploration (TSE) describes the activity occurring early in the design process through which stakeholders explore a broad solution space in search of more-optimal alternatives. In doing so, these stakeholders attempt to maximize the utility inherent in the chosen solution while understanding the tradeoffs and compromises that may be required to find an acceptable solution. In the field of vehicle design, tradespaces are often comprised of vast amounts of alternatives which increases the complexity of the decision-making process. Additionally, the number of stakeholders has grown, as decision-makers seek to include more variety in both perspectives and expertise. As such, decision-making stakeholders can often find themselves working at odds and attempting to maximize vastly different objectives in the process. One way to rectify these contrasting viewpoints can be to intentionally introduce a group framing prior to the start of decision making. In this experiment, teams of
Sutton, MeredithTurner, CameronHartman, GregoryGorsich, DavidSkowronska, Annette
During mining material hauling, the chassis frame structure of rear dump trucks is subjected to fatigue loading due to uneven road conditions. This loading often leads to crack propagation in the frame rails, necessitating the determination of stresses in the critical zone during the design stage to ensure structural integrity. In this study, a computer-aided engineering (CAE) methodology is employed to size and select the rectangular profile cross section of the chassis frame rail. A detailed design investigation of the chassis frame is conducted to assess its load resistance, structural flexibility, and weld joint fatigue life under critical stresses arising from combined bending and torsion loads. The optimization process aims to determine the optimal rail size and material thickness, striking a balance between minimizing mass and maximizing structural reliability. By achieving this, the risk of major structural failures during the transportation of large payloads can be
J, Avinash
For any two wheeler vehicle development, rider and pillion comfort while driving the vehicles over different kinds of road perturbations holds high importance. Designing a vehicle for comfort starts at the very beginning of its layout definition through vehicle geometric parameters, key hardpoints, mass-inertia distribution of subsystems and suspension characteristics. There is a need for highly reliable simulation models for comfort predictions as any change in layout during subsequent design stages is a very costly affair. Accurately predicting comfort using a full vehicle model is a challenging task though as it depends on how realistic the Simulation Model is to that of actual vehicle. While suspension stiffness and damping characteristics remain critical parameters for the comfort, selection of tyres are known to hold equal importance in vehicle comfort. The details to which the tyres are captured in the simulation model and the formulation of tyre interaction with roads in a
Govindula, SrikanthPandey, PradyumnSaraswat, UditMishra, Ashish
Electric vehicles (EV) are much quieter than IC engine powered vehicles due to less mechanical components and absence of combustion. The lower cabin noise in electric vehicles make customers sensitive to even small noise disturbances in vehicle. Road boom noise is one of such major concerns to which the customers are sensitive in electric vehicles. The test vehicle is a front wheel driven compact SUV powered by electric motor. On normal plain road, noise levels are acceptable but when the vehicle has been driven on coarse road, the boom noise is perceived, and the levels are objectionable. Multi reference Transfer Path Analysis (MTPA) is conducted to identify the path through which maximum forces are entering the body. Based on MTPA, modifications are proposed on the suspension bushes and the noise levels were assessed. Operational Deflection Shape (ODS) analysis is conducted on entire vehicle components like suspension links, sub frame, floor, roof, and doors to identify the
S, Nataraja MoorthyRao, ManchiRaghavendran, PrasathSelvam, Ebinezer
The current approach of hybrid RLDA is typically incapable of providing accurate dynamic loads coming on cab at chassis-to-cab load transfer locations, primarily due to the following two reasons. Firstly, all of the model parameters of the vehicle, which is put on the 4-post, are not known. Secondly, MBS (Multi-body System) Cab model is multi degree of freedom with rigid bodies, flex bodies, contacts and non-linear force elements. Therefore, if the system identification is to be performed manually it becomes an arduous and humanly impossible task. Towards generating accurate dynamic loads on cab, an approach using FEMFAT LAB - VI & MI has been developed which involves a two-step process: a) Generating MBS excitation by back calculating from measured frame response – VI (Virtual iterations). b) Fine tuning modelling parameters to match measured cab response – MI (Model Improvement). To execute the VI & MI approach for calculating dynamic loads on cab through 4-poster & 7-poster
Singh, PrempalPrasad, Tej
NVH is of prime importance in buses as passengers prefer comfort. Traditionally vehicle NVH is analysed post completion of proto built however this leads to modifications, increases cost & development time. In modern approach physical validation is replaced by CAE. There are many sources of NVH in vehicle however this article is focused about the methodology to improve NVH performance of bus by analysing and improving the stiffness and mobility of various chassis frame attachment points on which source of vibrations are mounted or attached. In this study chassis frame attachment stiffness of Engine mounts and propeller shafts is focused
Dhadiwal, Nishant SurendraPathak, RahulBijwe, VilasGore, Pandurang
As the world rapidly moves from IC engine powered vehicles to the ‘more sustainable’ electrified vehicles, the Powertrain Mounting System needs to be re-engineered to meet refinement requirements of customer. Electric vehicles are quieter but due to lack of the “masking effect”, are sensitive to minor disturbances that are perceived to be objectionable by passengers. Also, E-powertrains are lighter, produce higher torque at low rpms & operate at higher rpms which calls for different countermeasures for mounting systems compared to conventional single isolation 3-point mounting system as used in IC engines. Double isolation mounting system, where powertrain is connected to an auxiliary mass (sub frame/cradle) via mounts, which is suspended to the vehicle body via subframe bushes results in 12 rigid body modes, 6 for each mass, is highly effective in lowering the transmission of vibration at high frequencies. This paper discusses 12 DOF analytical tool developed to rapidly analyze the
Verma, ShemonJayachandran, Suresh KumarMane, YogirajPaua, KetanVellandi, Vikraman
Machine learning exerts a significant influence on the autonomous driving industry, enabling the development of self-driving vehicles. However, the performance of these models heavily relies on the quality and diversity of the training data. In situations where valid data is scarce, models struggle to make informed decisions. To address this obstacle, active learning methodologies are utilized for the purpose of choosing the most informative data frames from an extensive reservoir of unlabeled data. Uncertainty scores are calculated using methods like Least Confident and Entropy-based sampling, and frames with high uncertainty scores are manually annotated and added to the training dataset. This iterative process improves the model’s performance over time. This research study centers on assessing the application of active learning in diminishing the manual labor needed for data labeling through the selection of frames containing valuable information. A pre-trained YOLOv3 model is
Katariya, RashmiKumari, Anita
Light weighting in the automotive industry without the use of finite element methodologies is now inconceivable. With the development and enhancement of various CAE tools available, CAE-driven optimization has become part of the product development cycle. Using a variety of CAE techniques in a lightweight optimization process can significantly reduce product development lead time with good results. Traditional light weighting can be done through different iterative approaches with different manual inputs from cross-domain teams, which is usually time consuming and leads to repeated analysis. This method describes the case of a multi-domain optimization approach with the reduction of the frame weight of an e-scooter while considering important cross-domain load cases using CAE. For frame optimization, the important load cases such as Durability/Strength (Normal and Abusive), and NVH (Stiffness, Modes and Vibration) - were taken into account. This Multi Domain/Disciplinary Optimization
S, VishnuKakanur, AshokU PE, ManjunathaBhat, SachinPoojary, KiranV N, Kishor
A research team has developed a robotic system that can be unobtrusively built into the frame of a standard honeybee hive. Composed of an array of thermal sensors and actuators, the system measures and modulates honeybee behavior through localized temperature variations
For intelligent vehicles, a fast and accurate estimation of road slope is of great significance for many aspects, including the steering comfort, fuel economy, vehicle stability control, driving decision-making, etc. But the commonly used estimation methods nowadays usually demand additional sensors or complex dynamic models, causing increase in system complexity as well as decrease in accuracy. To solve these problems, this paper puts forward a real-time road slope estimation algorithm leveraging the relationship between pitch angle and road slope, which only requires low sensors cost and computational complexity. Firstly, a GNSS/INS fusion system is established to obtain the pitch angle with respect to the navigation frame, which couples the vehicle’s pitch angle in vehicle frame and road slope angle. Then, based on the different characteristics in frequency domain of the two components, frequency domain analysis is conducted and low-pass filter is used to separate out road slope
Chen, MengyuanXiong, LuGao, Letian
All two-wheeler industries validate their product’s fatigue life on proving track before heading for mass production. Proving test tracks are made to simulate the end-user environment in order to find out the possible fatigue failures during each development stage of vehicle design, which in turn helps the CAE analysts to verify the design before it goes to the end-user hands. In this article we present the design and failure analysis of sub-frame assembly of motorbike observed during the accelerated fatigue test on proving track. Sub-frame main rod was found broken exactly between two weld endings during fatigue test before reaching 6% of the target fatigue life. Possible causes of sub-frame failures have been identified/analyzed in detail using fish bone diagram. A finite element analysis (FEA) model of sub-frame assembly was developed and a random response analysis was carried out on initial design. Acceleration input loads measured from test track have been given at the sub-frame
Sharma, AshishKhare, Saharash
Due to their inherent properties and superior performance over titanium-based materials, nickel-based superalloys are widely utilized in the manufacturing industry. Monel 400 is among them. This nickel-copper alloy possesses exceptional corrosion resistance and mechanical properties. Monel 400 is primarily utilized in the chemical industry, heat exchangers, and turbine component manufacturing. Due to the properties of Monel 400, it is deemed as hard to machine materials with the aid of conventional methods. For investigating the performance of this process, a three-level analysis was carried out. Pulse on duration and applied current at three levels are the independent parameters used for designing the experiments. In this present article, a single-response analysis technique is used which is known as Taguchi to investigate the impact of the various process parameters on the output variables. They focused on three response factors namely the rate of material removal, deviation in the
Pasupuleti, ThejasreeNatarajan, ManikandanKumar, VKatta, Lakshmi NarasimhamuKiruthika, JothiSilambarasan, R
“The purpose of this study is to explore the structural behavior of motorcycle frames that are fabricated from metals such as steel and aluminum, and that are welded together to generate beams. The components of the wheel, handlebar, and saddle are assembled together to form the chassis of the bicycle. For the purpose of determining modal characteristics such natural frequencies and mode shapes, two different analytical approaches, namely finite element analysis (FEA) and experimental modal analysis (EMA), were utilized. The framework of the chassis was design in 3D using CAD software to carry out the FEA, and after specifying the meshing type and material parameters, normal mode analysis was carried out. To contrast modal characteristics with FEA results, EMA utilized impact hammer testing with a roving accelerometer approach. The study discovered differences between the two methods, which were effectively minimized to less than 10% by carrying out a model, update technique to
Prajapati, AkashBhaskara Rao, Lokavarapu
Deadweight as payload is an important parameter, which affects the vehicle dynamics and durability of the vehicle. This paper presents a study performed to evaluate the effect of deadweight on dynamic input load, suspension operation, and fatigue life of frame in a two wheeler. Also, an optimization exercise was undertaken to correlate and optimize deadweight with a human payload in terms of equivalent damage to the frame. Strain, wheel acceleration, and suspension displacement data were acquired with pillion and multiple deadweights and compared. Relative damage spectrum (RDS) characterization and best-fit optimization methods were used for deadweight correlation. It was observed that with deadweight addition dynamic loads decreases on the front wheel while increases on the rear. Strain damage wise increasing deadweights have marginal effects on the front zone of the frame while on the middle and rear side, deadweights are detrimental. Human payload behaves like deadweight for dynamic
Kumar, RajeshKumar, MohitIrfan, MdKumar, Pardiwan
A new simulation model for motorcycle motion is presented. The model was reproduced the equation of motion which called 10 degrees of freedom (10-DoF) motorcycle model using multi-body dynamics. There are some good reasons to reconstruct equation model by multi-body dynamics, because computer technology helped development of tools which is versatile to expand model. Straight line stability characteristics of motorcycle have been studied by using an equation of motion model for a long time. This model was originally developed by Sharp as a 4-DoF model, later Aoki developed 10-DoF model by adding 6-DoF to take frame stiffness into account. The eigenvalues of the Weave and Wobble mode showed some disagreement between the equation of motion model and the new multi-body dynamics model. The frame lateral bending is represented by the “equilibrium of lateral force” in the 10-DoF equation of motion. It turned out that “lateral force at bending Point” was not expressed in the equation. To make
Terayama, TakashiYamaguchi, ShotaKitagawa, HiroshiYabe, Noboru
The uncertainty of a driver’s state, the variability of the traffic environment, and the complexity of road conditions have made driving behavior a critical factor affecting traffic safety. Accurate predicting of driving behavior is therefore crucial for ensuring safe driving. In this research, an efficient framework, distilled routing transformer (DRTR), is proposed for driving behavior prediction using multiple modality data, i.e., front view video frames and vehicle signals. First, a cross-modal attention distiller is introduced, which distills the cross-modal attention knowledge of a fusion-encoder transformer to guide the training of our DRTR and learn deep interactions between different modalities. Second, since the multi-modal learning usually requires information from the macro view to the micro view, a self-attention (SA)-routing module is custom-designed for SA layers in DRTR for dynamic scheduling of global and local attentions for each input instance. Finally, a Mogrifier
Gao, JunYi, JiangangMurphey, Yi Lu
Truck maneuverability is one of the phenomena, which is considered in development stage of a commercial vehicle chassis structure. Torsional stiffness is one of the important properties of the chassis structure that significantly affects vehicle dynamic characteristics such as handling and rollover. The torsional stiffness is preferred to be as high as possible since lower torsional stiffness may cause resonance, vibration, poor handling, and rollover. Torsional stiffness can be improved through minor modification in the conventional ladder chassis frame. This paper presents the comparative study on improving the torsional stiffness of the chassis frame. The objective is to achieve the improved torsional stiffness by varying the neutral axis of the frame long member section at a desirable region. Torsional stiffness is dependent of the sectional modulus; this study provides an insight on increasing the torsional stiffness without addition of section modulus
Gowtham, G.V.N.Baashkaran, M.K.Naveen, Sukumar N.
Universal test frames are generally either screw-driven or servohydraulic, which are both perfectly suited for uniaxial tensile testing experiments. A uniaxial test frame is comprised of several basic fixture components: loading device, a load cell, and a specimen gripping apparatus
Editorial Note: With the growth in adoption of addititively manufactured materials across aerospace and defense manufacturing, we decided to include two parts of this Air Force Research Lab report. Air Force Research Laboratory, Wright-Patterson Air Force Base, OH Universal test frames are generally either screw-driven or servohydraulic, which are both perfectly suited for uniaxial tensile testing experiments. A uniaxial test frame is comprised of several basic fixture components: loading device, a load cell, and a specimen gripping apparatus. An example of a commercially available tensile testing frame is shown below. Load cells are available in a wide range of load limits to accommodate the sensitivity needs for a wide range of materials and specimen geometries. ASTM E74 outlines the calibration procedure for load cells and must be followed to ensure proper measurement during testing, regardless of specimen size. Further details about alignment and gripping will be provided given
Outokumpu and collaborators show a possible weight reduction of up to 35% by using high-strength stainless steel in place of carbon steel. The weight of a typical bus could be reduced by up to 35% - more than 1,000 kg (2,205 lbs.) - by using high-strength stainless steel to replace tubular bus-frame elements traditionally manufactured in carbon steel. That is the conclusion of a first-of-its-kind project carried out by stainless-steel manufacturer Outokumpu, together with CAD/CAE solution specialist FCMS, the Munich University of Applied Sciences and RotherCONSULT. Corrosion-resistant stainless steel could offer sustainability combined with reduced maintenance time and costs. In addition, high-strength stainless steel grades have become commercially available that offer significant weight savings. The aim of this project was to examine what that could mean in terms of lower weight and reduced material costs
Schuberth, StefanRother, KlemensPohl, Werner
Modifications have been implemented in the GlennICE software to accommodate a non-inertial reference frame. GlennICE accepts a flow solution from an external flow solver. It then introduces particles and tracks them through the flow field in a Lagrangian manner. Centrifugal and Coriolis terms were added to the GlennICE software to account for relative frame simulations. The objective of the present paper is twofold. First, to check that the new terms are implemented correctly and that the code still behaves as expected with respect to convergence. And second, to provide some initial insight into an upcoming propeller experiment in the NASA Icing Research Tunnel. The paper presents a description of the code modifications. In addition, results are presented for two operating conditions, and three particle sizes. Each case was simulated with four different grid densities to assess grid dependence
Rigby, Davidvon Hardenberg, Paul
Current modelling capability for engine icing accretion prediction is still limited for App. C. To further validate icing codes in complex engine geometries, it is necessary to perform additional experimental work in relevant geometrical and environmental conditions. Within the frame of ICE GENESIS [1], an experiment has been setup to replicate the condition at the inlet of an engine first stage compressor. This paper describes the choices for the design of the engine compressor model, the setup within the icing wind tunnel and the methodology employed to obtain the results. Additionally, more effort has been focused on obtaining accurate ice shapes using a 3D scanning system. Results of 3D scans are given
Pervier, HugoVénuat, ClémentNeubauer, Thomas
As an important vibration damping element in automobile, the rubber mount can effectively reduce the vibration transmitted from the engine to the frame. In this study, a method of parameters identification of Mooney-Rivlin model by using surrogate model was proposed to more accurately describe the mechanical behavior of mount. Firstly, taking the rubber mount as the research object, the stiffness measurement was carried out. And then the calculation model of the rubber mount was established with Mooney-Rivlin model. Latin hypercube sampling was used to obtain the force and displacement calculation data in different directions. Then, the parameters of the Mooney-Rivlin model were taken as the design variables. And the error of the measured force-displacement curve and the calculated force-displacement curve was taken as the system response. Two surrogate models, the response surface model and the back-propagation neural network, were established. In addition, their prediction accuracy
Sun, JiaweiLiu, Xiao-AngOu Yang, Yi-HongShangguan, Wen-Bin
Foaming materials such as 2C-PUR or expandable baffles are increasingly used in the car body acoustic package of modern passenger vehicles. Over the last several decades the primary function of foaming materials was the moisture sealing and airborne noise absorption / insulation in various areas of the car body such as pillars, door sills or other cavities. Recent developments also show an increasing application of expandable foams, functioning as structural dampers and reducing structure-borne noise transmission through frames and pillars. This paper summarizes the results of various studies that deal with the impact of expandable baffle materials on structure-borne noise in car bodies with special focus on mid and high frequencies which become more relevant in the acoustic optimization efforts of EV’s. Structural vibrations are evaluated experimentally on foamed generic frames and double sheet metal systems under free-free boundary conditions. The most promising candidate among
Unruh, OliverObst, Heike-UrsulaFuhrmann, BerndBautista, Jose
As an important vibration damping element in automobile industries, the vibration transmitted from the engine to the frame can be reduced effectively because of rubber mount. The influence of preload on the static characteristics of rubber mount and the constitutive parameters identification of Mooney-Rivlin model under preload were studied. Firstly, a test rig for stiffness measurement of rubber mount under preload was designed and the influence of preload on the force versus displacement of mount was studied. Then, the model for estimating force versus displacement of rubber mount was established. The response surface model for parameters identification was established. And the identification method for estimating parameters of Mooney-Rivlin model of rubber mount was proposed with the crow search algorithm. Taking the rubber mount as the research object and taking the parameters of Mooney-Rivlin model as the variables. Then, using response polynomials corresponding to different force
Sun, JiaweiLiu, XiaoangOu Yang, Yi-HongShangguan, Wenbin
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