Browse Topic: Vehicle performance

Items (1,417)
The comfort of seats increasingly becomes a crucial factor in the overall driving experience, particularly as vehicles become increasingly integrated into people’s daily lives. Passengers often maintain a relatively fixed posture and have close contact with the seat for extended periods of time, leading to issues such as heat, humidity, and stickiness. In order to enhance the thermal comfort experienced by occupants, manufacturers are no longer satisfied with ensuring the thermal comfort performance of vehicles only through the HVAC system in the cabin, but also developed a microclimate control seat that adjusts the temperature through ventilation between the contact surface of the seat and the human body, trying to improve the thermal comfort of passengers more effectively. However, the ventilation ducts of these seats are commonly designed based on empirical or autonomous standards, and their effectiveness is subsequently assessed through test or simulation, typically under unloaded
Zhang, TianmingRen, JindongZhang, Haonan
Terramechanics is a pivotal field for understanding the interaction between a vehicle’s tires and the terrain. Over time, numerous models have been developed to predict the performance of wheeled vehicles across different terrains. This study aims to employ Bekker’s model, which considers the deformable ground and the rigid tire, to simulate the motion of a 4x4 off road vehicle using the Matlab Vehicle Dynamics Blockset. The methodology of this study involves the use of a MatLab Simulink blockset diagram in conjunction with Bekker’s theory to describe the tire’s interaction with the soil. This approach will enable us to obtain the vehicle’s longitudinal dynamics, including position and velocity. The primary goal of this study is to juxtapose the simulated motion with the model provided by Matlab. This comparison will serve to validate Bekker’s theory. By achieving this, we aim to contribute to the body of knowledge in the field of terramechanics and enhance the predictive accuracy of
Duque, Gabriel LeonardoUchôa, Lucas Etchells RileyLopes, Elias Dias RossiRodrigues, Gustavo Simão
Road loads, encompassing aerodynamic drag, rolling resistance, and gravitational effects, significantly impact vehicle design and performance by influencing factors such as fuel efficiency, handling, and overall driving experience. While traditional coastdown tests are commonly used to measure road loads, they can be influenced by environmental variations and are costly. Consequently, numerical simulations play a pivotal role in predicting and optimizing vehicle performance in a cost-effective manner. This article aims to conduct a literature review on road loads and their effects on vehicle performance, leveraging experimental data from past studies from other researchers to establish correlations between measured road loads and existing mathematical models. By validating these correlations using real-world measurements, this study contributes to refining predictive models used in automotive design and analysis. The simulations in this study, utilizing five distinct empirical
Pereira, Leonardo PedreiraBraga, Sérgio Leal
This study investigates the effects of replacing a 6-speed gearbox with a 5-speed gearbox in a sports vehicle, while keeping all other parameters constant. Through computational simulations, data is collected for comparative performance analysis. The study aims to understand the potential implications of this change on acceleration, fuel efficiency, engine response, as well as aspects such as driver comfort. The results may provide valuable insights for the automotive industry, guiding future transmission design and engineering decisions
Marinho, Gabriel Jannuzzide Campos, Josué QueirozLopes, Elias Dias RossiRodrigues, Gustavo Simão
SBW(Steer-by-wire) is a steering system that transmits the driver’s request and gives feedback to the driver through electrical signals. This system eliminates the mechanical connection of the traditional steering system, and can realize the decoupling of the steering wheel and the road wheel. In addition, this system has a perfect torque feedback system, which can accurately and delicately feedback the road surface information to the driver. However, vehicle driving deviation is one of the most common failure modes affecting vehicle performance in the automotive aftermarket, this failure mode can exacerbates tire wear, reducing their life cycle, at the same time, the driver must apply a counter torque to the steering wheel for a long time to maintain straight-line travel during driving. This increases the driver’s operational burden and poses safety hazards to the vehicle’s operation. Based on the steer-by-wire system and vehicle driving deviation characteristics, this paper proposes
Xiangfei, XuQu, Yuan
As a journey to green initiatives, one of the focus areas for automotive industry is reducing environmental impact especially in case of internal combustion engines. Latest digital twin technology enable modelling complicated, fast and unsteady phenomena including the changes of emission gases concentration and output torque observed during diesel emission and combustion process. This paper presents research on the emission and combustion characteristics of a heavy vehicle diesel engine, elaborating an engineered architecture for prognostics/diagnostics, state monitoring, and performance trending of heavy-duty vehicle engine (HDVE) and after treatment system (ATS). The proposed architecture leverages advanced modeling methodologies to ensure precise predictions and diagnostics, using data-driven techniques, the architecture accurately model’s engine and exhaust system behaviors under various operating conditions. For exhaust system, architecture demonstrates encouraging predictive
Singh, PrabhsharnThakare, UjvalHivarkar, Umesh
Spot welds are integral to automotive body construction, influencing vehicle performance and durability. Spot welding ensures structural integrity by creating strong bonds between metal sheets, crucial for maintaining vehicle safety and performance. It is highly compatible with automation, allowing for streamlined production processes and increased efficiency in automotive assembly lines. The number and distribution of spot welds directly impact the vehicle's ability to withstand various loads and stresses, including impacts, vibrations, and torsion. Manufacturers adhere to strict quality control standards to ensure the integrity of spot welds in automotive production. Monitoring spot weld count and weld quality during manufacturing processes through advanced inspection techniques such as Image processing by YOLOv8 helps identify the number of spots and quality that could compromise safety. Automating quality control processes is paramount, and machine vision offers a promising
Kadam, Shubham NarayanDolas, AniketMishra, Jagdish
Typically, an automotive passenger car wheel rim can withstand gradual loading contributed from the vehicle during cornering and high-speed maneuvering and as per the standard as well as customer requirements wheel has to withstand some impact forced contributed from radial and inclined loading. But in some cased wheel rim may not withstand the impact forces generated during impact on potholes and curbs with high-speed maneuvering. This Study helps to understand the impact on wheel rim and the forces acting on the rim flanges during pothole impact and high-speed curb impact. For In this study author tends to explain about the design of the rim flanges considering the impact forces the wheel rims are exposed to during pothole impact. Also in this study, road load data for a double pothole impact in electric vehicle with lightest alloy wheel rim in the segment is acquired to understand the loads acting on the rim. Based on the simulation iterations with several design changes and
Thiyagarajan, SriramJithendhar, ASingh, Ram KrishnanSundaram, RaghupathiPaua, Ketan
Electric vehicles are regarded to be the most effective way to lower emissions of greenhouse gases from the transportation industry. Lithium-ion batteries are rechargeable and ideally suited for vehicle electrification due to their high specific energy and energy density in comparison to other batteries. Electric vehicle performance greatly depends on the efficient operation of lithium-ion battery. Battery thermal management plays a crucial role in ensuring optimum vehicle operation. Heat dissipation from the battery should be dealt with, for safe operation and to prolong the battery life cycle. To achieve the battery’s optimal temperature, an efficient cooling system should be established. The battery cooling plate is an essential component that is necessary for heat transfer from the battery pack to the coolant. Five different battery cooling plates with linear dimple, staggered dimple, straight channel, wave channel and splitter channel are modeled for computational fluid dynamics
K, MuthukrishnanS, SaikrishnaK, Keshavbalaje
This paper presents a comprehensive methodology for sizing an electric motor for a given vehicle performance targets and analyzing the motor performance at different operating zones of the electric vehicle. Designing the powertrain of an electric vehicle starts with understanding the on-road performance requirements of the vehicle relevant to the application such as top speed, gradient and acceleration targets. It is critical to define the operating performance boundary of the vehicle based on end user preference. This paper illustrates a comprehensive approach of implementing 1D simulation tool namely GT-SUITE to simulate the vehicle model for different on-road performance targets so as to conclude the traction motor specifications [3]. These specifications along with the other boundaries of the vehicle such as battery limitations and MCU limitations are taken as input parameters for the electromagnetic simulation assisted by Ansys Motor-CAD to design optimized motor that can meet the
Ghule, Gopal ArjunNeelakantan, Subramoniyan
In the realm of commercial vehicle design, enhancing the durability of bumpers and headlamps is paramount for ensuring safety and reducing maintenance costs. This study explores the development of a lightweight bumper design with optimized resonance frequency to improve the durability of these critical components. The research focuses on innovative design techniques to achieve a balance between weight reduction and structural integrity. The primary objective is to minimize the impact forces transmitted to the bumper and headlamp assemblies during vibrations. By employing finite element analysis (FEA) and experimental validation, the study identifies the optimal resonance frequency that mitigates the risk of resonance-induced damage. Additionally, the study examines the influence of geometric modifications on the bumper’s performance. Various design iterations are analyzed to determine the most effective configuration for enhancing durability while maintaining compliance with industry
Pandey, SudheerGanesan, Balaji
Clutch wear is a significant factor affecting vehicle performance and maintenance costs, and understanding its dynamics is crucial for original equipment manufacturers (OEMs) to enhance product reliability and customer satisfaction. It is important to predict clutch wear to enable customers to understand the condition of their clutch and the remaining clutch life, to avoid sudden vehicle breakdowns. This paper explains the approach of measuring the clutch wear profile on an actual vehicle and simulating the same conditions on a powertrain test bench, with the establishment of a correlation in clutch wear profiles
Chopra, ChandanKumar, VarunMamidigumpula, Mohan Kumar Reddy
Torque vectoring offers drive flexibility and continuous individual wheel torque regulation, which is unavailable in conventional transmission systems. Electric vehicles with multiple drivetrains and torque-vectoring system can significantly enhance vehicle response and handling, and thus the active safety, efficiency, and performance of the vehicle in all driving conditions. The current methodology of predicting performance characteristics is limited through slip rate calculations and yaw rate calculations. The vehicle dynamic performance evaluations with above said methodologies holds good for dynamic cornering. But in the scenarios where the vehicle moving in straight drive with different wheel traction requirements on either side (split-μ condition) and that requires torque vectoring. These above methods do not help to evaluate the performance of vehicle. Because these methodologies are based on predicting dynamic center-of-gravity values of vehicle. In the proposed methodology
Ramakrishnan, Gowtham RajBaheti, Palash
Dynamic Vehicle mass is one of the most critical parameters in automotive controls such as battery management, transmission shift scheduling, distance-to-empty predictions and most importantly, various active and passive safety systems. This work aims to find out dynamic Vehicle mass for Electric Vehicles in real time transient driving conditions. The work proposes a real-time approach in finding Dynamic vehicle mass where accumulated Energy based vehicle performance, an improvement to the vehicle dynamics equation, has been employed for consistent and accurate results. Factors affecting vehicle mass such as road grade, dynamic friction coefficient, driving pattern, wheel slip etc. have been considered for model optimization. Here recursive Bayesian state estimator has been used for finding vehicle mass as a constant state variable while time varying forgetting factors are used to nullify the impact of major losses. Algorithm is auto tuned using Machine Learning techniques to first
Pandey, SuchitSarkar, PrasantaSawhney, ChandanKondhare, ManishJoshi, PawanCH, Sri Ram
The estimation of vehicle handling and control parameters in dynamic conditions is challenging due to errors and delays in real-time data logging with low-resolution onboard sensors. These issues significantly impact the performance of vehicle stability and control algorithms, particularly in vehicles under testing. This study presents error mapping concept parallel to statistical error method for real-time vehicle state estimation that addresses the limitations of low-resolution sensors with errors and delays in measured signal. In this study, a real-time (RT) model is developed and trained with in-house electric SUV to estimate yaw velocity and slip angle. The model leverages other measured signals available from the vehicle’s onboard sensor setup. It integrates an error and delay function with error predictive model to estimate the targeted parameter signal response in real time. The RT model introduces an error function method that enhances prediction accuracy by combining the
Kumar, AvinashAsthana, ShivamRasal, ShraddheshM, SudhanVellandi, Vikraman
ABSTRACT The paper presents the fuel economy and performance capabilities of a switchable P2/P3 Hybrid Transmission for commercial and military use cases through modeling and simulation. An overview of the simulation model developed to analyze the vehicle performance and fuel consumption for a specified drive cycle is presented. The model includes the key components of the electrified powertrain including engine, hybrid transmission, electric motor and battery. Use cases were identified to represent Commercial vocational applications and military analogues. The results of P2/P3 Hybrid Powertrain model simulation are compared with that obtained from a model of baseline Conventional Torque Converter Automatic Transmission (AT). The comparison is made for both vehicle performance and fuel economy, and the results indicate that the P2/P3 Hybrid Transmission demonstrates better fuel economy with same or better performance than the baseline heavy-duty automatic transmission. Opportunities to
Patil, ChinmayaThanom, WittDykes, ErikKreucher, JoshGenise, Thomas
ABSTRACT Tracked vehicles are known to provide excellent off-road mobility, but traditional steel tracks do come with some important compromises. The recent introduction of Composite Rubber Tracks (CRT) on the CV90 IFV (77,000 lb) has shown that this robust and operationally proven CRT technology significantly reduces the vehicle weight, fuel consumption, noise, and vibration levels. Inspired by this new enthusiasm for tracked vehicles, provided by CRT, armies and original vehicle manufacturers initiated a series of independent trials confirming the benefits and reliability of CRT. The author’s objective is to present the conclusions of these independent CRT trials, more specifically focusing on the Warrior IFV, providing substantiation data on how CRT technology enhances tracked vehicle performance
Marcotte, Tommy
ABSTRACT A retrofittable intelligent vehicle performance and fuel economy maximization system would have widespread application to military tactical and non-tactical ground vehicles as well as commercial vehicles. Barron Associates, Inc. and Southwest Research Institute (SwRI) recently conducted a research effort in collaboration with the U.S. Army RDECOM to demonstrate the feasibility of a Fuel Usage Monitor and Economizer (FUME) – an open architecture vehicle monitoring and fuel efficiency optimization system. FUME features two primary components: (1) vehicle and engine health monitoring and (2) real-time operational guidance to maximize fuel efficiency and extend equipment life given the current operating conditions. Key underlying FUME technologies include mathematical modeling of dynamic systems, real-time adaptive parameter estimation, model-based diagnostics, and intelligent usage monitoring. The research included demonstration of the underlying FUME technologies applied to a
Burkholder, Jason O.Ostrowski, Gregory J.Beck, Christopher S.
ABSTRACT The intent of the Advanced Propulsion with Onboard Power (APOP) system is to increase the available onboard power for the Stryker from 16kW (570A) to 120kW to support future vehicle capabilities such as directed energy, electromagnetic armor, and electronic warfare. The additional power is also used to run electrified automotive auxiliaries on the vehicle such as the main fan and the hydraulic pump more efficiently. Vehicle test results showed that the APOP vehicle had better or equivalent performance to the baseline vehicle when just the electrified automotive auxiliaries are included, but additional future loads still pose a challenge to meeting vehicle performance requirements
Boice, KevinAbdallah, YoussefTylenda, Josh
ABSTRACT As new subsystems are integrated onto existing ground combat vehicle platforms for capability enhancement purposes, the demand for electrical power output increases. In many cases these enhancements exhaust the available output power reserves and leads to performance capability plateau for some of the existing power systems. This increased power demand may sometimes cause the vehicle’s generator to become fully loaded, causing any energy shortfalls to be covered by the battery storage system. When a high percentage of system power is routinely provided by the battery system without optimized battery management, the result is degraded battery capacity that leads to frequent battery replacement. This paper addresses specific limitations of ground combat vehicle power systems related to insufficient power output capacity and deficient battery management practices. Additionally, the paper will discuss concepts that enhance battery management capability and extend the operational
Palmer, JasonHamilton, GeorgeSmith, MichaelWright, Ronnie L.
ABSTRACT Seasonality plays a key role in altering the terrain of many military operating environments. Since seasonality has such a large impact on the terrain, it needs to be properly accounted for in vehicle dynamics models. This work outlines a variety of static and dynamic seasonal terrain conditions and their impacts on vehicle mobility in an austere region of Europe. Overall the vehicles performed the best in the dry season condition. The thaw season condition had the most drastic impact on mobility with all but the heavy tracked vehicle being almost completely NOGO in the region. Overall, the heavy tracked vehicle had the best performance in all terrain conditions. These results highlight the importance of incorporating seasonal impacts on terrain into NRMM or any vehicle dynamics model. Future work will focus on collecting more data to improve the empirical relationships between vehicles and seasonal terrain conditions, thereby allowing for more accurate speed predictions
Hodgdon, Taylor S.Shoop, Sally A.Frankenstein, SusanBigl, Matthew F.Parker, Michael W.
ABSTRACT Vehicle electrification technology has demonstrated its effectiveness for passenger vehicles, mainly due to environmental performance needs to meet fuel economy and green-house-gas emissions standards. Military vehicles require, among other specific features, not only the ability to move undetected but to perform at the lowest combined fuel and energy consumption possible. An experimental prototype HMMWV XM1124 with a series hybrid powertrain, which provides the ability for electric mode only and hybrid operation for reducing fuel consumption, is being investigated. The aim of this paper is to create a model of XM1124, validate it and utilize it to analyze the effect of vehicle electric range and performance. Additionally, the validated model allows evaluation of various operating strategies and hardware configurations for reducing the fuel consumption and improving vehicle performance
Gauchía, A.Worm, J.Davis, C.Naber, J.
ABSTRACT Ker-Train Research Inc. (KTR) in collaboration with Southwest Research Institute (SwRI), Control Point Corporation (CPC) and the Tank Automotive Research Development and Engineering Center (TARDEC) Ground Vehicle Power and Mobility (GVPM) has completed the design and fabrication of an efficient Bradley Fighting Vehicle (BFV) power take-off (PTO) fan drive system with electronic controls to demonstrate performance gains in top speed and speed on grade as well as provide fuel savings. This paper provides information on the 8-speed fan drive design, technology, and binary logic architecture. The history of the fan drive development is also discussed
Marquardt, BrentBrown, MichaelGoryca, MaryStempnik, JoePesys, Tomas
ABSTRACT Defence R&D Canada – Suffield has undertaken a research project to investigate the practicality of an operationally quiet hybrid-electric snowmobile. This paper reports on the design of, and the testing conducted with, a prototype noise-reduced hybrid-electric snowmobile. The project goals were to ascertain the practicality of such a design and to determine the baseline achievable noise reduction prior to any optimization. The project has overcome most of the technological hurdles, producing a solid basis for future work. The vehicle performed well in military user testing
Ouellette, SimonGiesbrecht, JaredKuyek, DavidDe Broux, FrancisProulx, Olivier
Summary This paper discusses the latest techniques in vehicle modeling and simulation to support ground vehicle performance and fuel economy studies, enable system design optimization, and facilitate detailed control system design. The Autonomie software package, developed at Argonne National Laboratory, is described with emphasis on its capabilities to support Model-in-the-Loop, Software-in-the-Loop (SIL), Component-in-the-Loop (CIL), and Hardware-in-the-Loop simulations. Autonomie supports Model-Based Systems Engineering, which is growing in use as ground vehicles become more sophisticated and complex, with many more subsystems interacting within the vehicle and the environmental conditions in which the vehicles operate becoming more challenging and varied. With the advent of hybrid powertrains, the additional dimension of vehicle architecture has become one of the design variables that must be considered. This complexity results in the need for a simulation tool that is capable of
Michaels, LarryHalbach, ShaneShidore, NeerajRousseau, Aymeric
ABSTRACT The HMPT500-3 is a split torque path hydrostatic / mechanical CVT used in the Bradley Fighting Vehicle. A previous paper detailed a linear algebraic approach to model forward operation of the HMPT500-3 without steering using a reduced equation set. This model was expanded to the full equation set to allow transmission operation with steering. The equations showed that opposite to a typical automotive “open” differential, the HMPT500-3 enforces a speed difference between the sprockets for steering, but does not have an inherent torque bias. The typical regenerative steering torque from the decelerated inside track must be provided by interfacing with a vehicle model. A simplified 2-D planar dynamics model of the Bradley was developed to explore vehicle performance and fuel consumption with steering. The integrated model showed that fuel consumption during minimum radius turns can double that of straight-ahead operation at the same speed. Commercial vehicle performance codes
McGough, Matthew G
ABSTRACT This paper presents a novel approach for modeling LAV-terrain systems in a dynamic simulation environment, which is based on results from the research and development of advanced technologies by the Computer Modeling and Simulation team of General Dynamics Land Systems-Canada (GDLS-C). The presented soil-tire model has been developed based upon the application of terra-mechanics and is being uniquely integrated with a full 8x8 LAV model in ADAMS/View, with incorporation of large tire deflections and multi-passing effect. It is shown that the highly efficient soil-tire model is capable of dynamically predicting soil sinkage, tire deflection, wheel slip, rolling resistance, drawbar pull and actual torque created at each soil-tire interface, as required by the mobility analysis of LAV systems over soft terrains
Zhang, XiongKnezevic, Zeljko
ABSTRACT A significant challenge for wheel- and propeller-driven amphibious vehicles during swimming operations involves the egress from bodies of water. The vehicle needs to be able to swim to the ramp of a vessel, and then propel itself up the ramp using water propellers and wheels simultaneously. To accurately predict the ability of the vehicle to climb the ramp, it is important to accurately model: (1) the interaction of the flow through the propellers, around the vehicle hull, and away from the ramp; (2) the wheel / ramp interaction; (3) the suspension system spring, damping, and motion-limiting forces, tire deformation and loading characteristics, and wheel and hull motions (both translation and rotation); and (4) the drivetrain power distribution to the wheels. Detailed modeling and simulation of these physics and processes -- such as the wheel, hull, and suspension system motions and force interactions, propeller rotation and resulting flow, etc. -- would be highly
Tison, Nathan
ABSTRACT Durability analysis as applied to high mobility off-road ground vehicles involves simulating the vehicle on rough terrains and cascading the loads throughout the structure to support the verification of various components. For components within the hull structure, the rigid body accelerations of the hull are transformed to the component location producing a prescribed g-load time history. This modeling method works extremely well for items which are bolted in place but is inappropriate for stowage systems such as boxes and shelves where cargo can experience intermittent contact and impacts. One solution is to create a dynamic contact nonlinear finite element model of the stowage solution with supported cargo and subject them to the same acceleration profile. This approach effectively resolves the stresses needed to perform fatigue evaluations but is a computationally and labor intensive process. The resources required for single design point verification cannot be justified
Purushothaman, NammalwarCritchley, JamesHulings, JessicaJoshi, Amarendra
ABSTRACT Model based design techniques are being used increasingly to predict vehicle performance before building prototype hardware. Tools like ADAMS and Simulink enable very detailed models of suspension components to be developed so vehicle performance can be accurately predicted. In creating models of vehicle systems, often there is a question about how much component detail or model fidelity is required to accurately model system performance. This paper addresses this question for modeling shock absorber performance by comparing a low fidelity and high fidelity shock absorber model. A high fidelity and low fidelity mathematical model of a shock absorber was developed. The low fidelity shock absorber model was parameterized according to real shock absorber hardware dimensions. Shock absorber force vs. velocity curves were calculated in Simulink. The results from the low fidelity and high fidelity model were compared to shock absorber force vs. velocity test results. New vehicle
Masini, ChrisYang, Xiaobo
ABSTRACT As part of the campaign to increase readiness in northern regions, a near commercial-off-the-shelf (COTS) solution was identified for the High Mobility Multipurpose Wheeled Vehicle (HMMWV); and used to assess the suitability of commercially available winter tires for operational deployment. Initial performance evaluations conducted during the winters of 2020 and 2021 demonstrated and quantified significant improvements to traction and handling on a variety of winter surfaces. User feedback from United States Army Alaska (USARAK) Soldiers confirmed these results in an operational environment. Results of this study provide new winter tire specifications for the Army and justify the procurement of a HMMWV winter tire for improved safety and capability for US Soldier and vehicle fleet needs. The data and Soldier evaluations support attaining a National Stock Number (NSN) and provide data to develop models of winter vehicle performance that include the impact of winter tires and
Shoop, SallyWitte, CliffordKarwaczynski, SebastianEllis, CliftonMatthews, EoghanBishel, StevenBomier, BarryMcCullough, RonaldParker, MichaelMartin, ScottKamprath, NathanWelling, OrianElder, Bruce
ABSTRACT A discussion on the utility of physics-based compact thermal models to guide the design, integration, operation and control of thermally sensitive vehicle components is presented. Effective component selection requires honest and accurate representation of the key performance attributes expressed by physics-based models. Parallel developments and lessons learned from the Electronics Industry on component packaging and characterization is discussed. An example application of a physics-based model driven design is presented for an Electrical Energy Dissipater design used on typical hybrid vehicles. Low fidelity models are used early in the design to support system requirements decomposition into discreet design attributes. High fidelity thermal and electromagnetic models are used to explore the design space and to optimize performance metrics. Accurate and robust reduced order thermal models are used for the continuous prognostic, diagnostic monitoring and control of the device
Kassinos, AdonisLippsmeyer, JeffreyWebb, Steven
ABSTRACT Ker-Train Research Inc. has designed and manufactured a 32-speed tracked-vehicle transmission and an 8-speed efficient power take-off fan drive that have been shown through testing to not only increase vehicle performance and overall system efficiency, but also have the ability to be controlled fully drive-by-wire making them excellent candidates for integration into autonomous vehicles
Brown, MikeMarquardt, Brent
ABSTRACT Two notional path-clearing tracked-vehicle models are part of this exploration in assessing the capabilities and limitations of the state-of-the-art in tracked vehicle dynamics modeling and simulation over soft-soil terrain. Each vehicle utilized different path-clearing methods that presented challenges in modeling their interactions with the soil: one vehicle used a roller and rake combination. The roller pressured the soft soil while the rake sheared it. The other vehicle used a quickly rotating flail system that cleared a definitive path by impacting and flinging the soil away. One vehicle had a band track and the other had a segmented track introducing additional modeling challenges. Each of these design choices was independently varied and analyzed. Path clearing performances and design sensitivities to track properties were studied in addition to the effect of contact forces between track, road wheels, idler, and sprocket. Vehicle performance on differing soil types is
Raymond, Joseph BJayakumar, Paramsothy
ABSTRACT With US military casualties mounting due to Improvised Explosive Devices (IEDs) and other roadside bombs, improving the protective capabilities of armored vehicles for service personnel is of paramount importance. Accurate numerical simulations of the blast event provide a means to quickly and economically evaluate the blast-protection performance of armored vehicles, and to develop improved blast countermeasures. This effort developed computational simulations of a system intended to mitigate blast accelerations to a level where the acceleration is no longer a lethal threat to the occupants of an armored vehicle. The hypothesis is that through the manipulation of the mass ratio, stiffness and damping properties of a dual-hull system, the capability of current Mine Resistant Ambush Protected (MRAP) vehicles can be greatly improved. The results show that, in comparison to the standard single-hull vehicle, the dual-hull vehicle reduces head injury criteria by 95.7%, neck
Schaffner, GrantMiller, Adam
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