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Training / Education

Fundamentals of GD&T ASME Y14.5 2018 - Advanced Level

2024-07-02
This 3-day Fundamentals of GD&T course provides an in-depth study of the terms, rules, symbols, and concepts of geometric dimensioning and tolerancing, as prescribed in the ASME Y14.5-2018 Standard. The course can be conducted in three 8-hour sessions or with flexible scheduling including five mornings or five afternoons. 
Training / Education

Design of Experiments (DOE) for Engineers

2024-05-15
Design of Experiments (DOE) is a methodology that can be effective for general problem-solving, as well as for improving or optimizing product design and manufacturing processes. Specific applications of DOE include identifying proper design dimensions and tolerances, achieving robust designs, generating predictive math models that describe physical system behavior, and determining ideal manufacturing settings. This course utilizes hands-on activities to help you learn the criteria for running a DOE, the requirements and pre-work necessary prior to DOE execution, and how to select the appropriate designed experiment type to run.
Training / Education

Weibull-Log Normal Analysis Workshop

2024-05-14
RMS (Reliability-Maintainability-Safety-Supportability) engineering is emerging as the newest discipline in product development due to new credible, accurate, quantitative methods. Weibull Analysis is foremost among these new tools. New and advanced Weibull techniques are a significant improvement over the original Weibull approach. This workshop, originally developed by Dr. Bob Abernethy, presents special methods developed for these data problems, such as Weibayes, with actual case studies in addition to the latest techniques in SuperSMITH® Weibull for risk forecasts with renewal and optimal component replacement.
Training / Education

Design for Manufacturing & Assembly (DFM/DFA)

2024-05-13
Design for Manufacturing and Assembly (DFM+A), pioneered by Boothroyd and Dewhurst, has been used by many companies around the world to develop creative product designs that use optimal manufacturing and assembly processes. Correctly applied, DFM+A analysis leads to significant reductions in production cost, without compromising product time-to-market goals, functionality, quality, serviceability, or other attributes. In this two-day course, you will not only learn the Boothroyd Dewhurst Method, you will actually apply it to your own product design!
Technical Paper

Assessing the Effects of Computational Model Parameters on Aerodynamic Noise Characteristics of a Heavy-Duty Diesel Engine Turbocharger Compressor at Full Operating Conditions

2024-04-09
2024-01-2352
In recent years, with the development of computing infrastructure and methods, the potential of numerical methods to reasonably predict aerodynamic noise in compressors has increased. However, aerodynamic acoustic modeling of complex geometries and flow systems is currently immature, mainly due to the greater challenges in accurately characterizing turbulent viscous flows. Therefore, recent advances in aerodynamic noise calculations for automotive turbocharger compressors were reviewed and a quantitative study of the effects for turbulence modeling (Shear-Stress Transport (SST) and Detached Eddy Simulation (DES)) and time-steps (2°and 4°) in numerical simulations on the performance and acoustic prediction of a compressor under full operating conditions was investigated. The results showed that for the compressor performance, the turbulence models and time-step parameters selection were within 1.5% error of the simulated and measured values for pressure ratio and efficiency.
Technical Paper

Powertrain control via model predictive rollout scheme

2024-04-09
2024-01-2141
Multi-motor powertrain topologies are playing an increasingly important role in the development of heavy duty battery electric trucks due to the changing driving requirements of these vehicles. The use of multiple motors and/or transmissions in a powertrain provides additional degrees of freedom for the energy management. The energy management system (EMS) consist of the gear selection strategy and torque split between the drive motors. The aim of the EMS is thereby to achieve high energy efficiency in motor and regenerative operation, while reducing the number of gear changes to ensure driving comfort. Ongoing research focuses on the energy management system of hybrid electric trucks, where the aim is to optimize the torque split between the combustion engine and the electric motor. In this paper, the EMS for an electric truck is described as a mixed-integer nonlinear control problem. This type of optimal control problem is notoriously difficult to solve.
Technical Paper

Introduction of the eGTU – an electric version of the Generic Truck Utility Aerodynamic Research Model

2024-04-09
2024-01-2273
Common aerodynamic research models have been used in aerodynamic research throughout the years to assist with the development and correlation of new testing and numerical techniques, in addition to being excellent tools for gathering fundamental knowledge about the physics around the vehicle. In 2020, the Generic Truck Utility (GTU) was introduced by Woodiga et al. following the success of the DrivAer, originally introduced by Heft et al. in 2012, in the automotive aerodynamics space but with a goal to capture the unique flow fields created by pickups and large SUVs. To date, a number of studies have been presented on the GTU (Howard et. al 2021, Gleason, Eugen 2022), however, with the increasing prevalence of electric vehicles (EVs), the authors have created additional configurations to create an EV-style underbody for the GTU. The existing GTU can change the cab and box lengths independently and has a rear cap with three different backlight angles to model SUVs.
Technical Paper

Optimal Control Co-Design of a Parallel Electric-Hydraulic Hybrid Vehicle

2024-04-09
2024-01-2154
This paper presents optimal control co-design of a parallel electric-hydraulic hybrid powertrain, to be specific, for heavy-duty vehicles. A pure electric powertrain that consists of a rechargeable lithium-ion battery, a high-efficient electric motor, and a single or double-speed gearbox has drawn a keen interest in the automotive sector because of a growing demand for clean and efficient mobility. However, the state-of-the-art has shown limited capability and has not been able to meet the design requirements for heavy-duty vehicles of high-power demand such as a class 8 semi-trailer truck in terms of a driving range on one battery charge, battery charging time, and load-carrying capacity primarily due to the low power density of lithium-ion batteries and low energy conversion efficiency of electric motors at low speed.
Technical Paper

A Holistic Approach to Next-Generation Polymer Composite Pickup Bed Development and Prototyping

2024-04-09
2024-01-2432
As we move toward electrification in future mobility, weight and cost reduction continue to be priorities in vehicle development. This has led to continued interest in advanced molding processes and holistic design to enable polymer materials for demanding structural applications such as pickup truck beds. In addition to performance, it is necessary to continue to improve styling, functionality, quality, and sustainability to exceed customer expectations in a competitive market. To support development of a lightweight bed design, a cross-functional team objectively explored the latest materials and manufacturing technologies for this application. In Phase 1 of this work, presented in 2022, the team considered a variety of alternatives for each functional area of the bed, including thermoplastic and thermoset materials with a range of processing technologies.
Technical Paper

A Numerical Analysis of Terrain and Vehicle Characteristics in Off-Road Conditions Through Semi-Empirical Tyre Contact Modelling

2024-04-09
2024-01-2297
In the last decades the locomotion of wheeled and tracked vehicles on soft soils has been widely investigated due to the large interest in planetary, agricultural, and military applications. The development of a soil contact model which accurately represents the micro and macro-scale interactions plays a crucial role for the performance assessment in off-road conditions since vehicle traction and handling are strongly influenced by the soil characteristics. In this framework, the analysis of realistic operative conditions turns out to be a challenging research target. In this research work, a semi-empirical model describing the interaction between a tyre and homogeneous and fine-grained soils is developed in Matlab/Simulink. The stress distribution and the resulting forces at the contact are based on well-known terramechanics theories, such as pressure-sinkage Bekker’s approach and Mohr-Coulomb’s failure criterion.
Technical Paper

Fuzzy Control of Regenerative Braking on Pure Electric Garbage Truck Based on Particle Swarm Optimization

2024-04-09
2024-01-2145
In order to improve the braking energy recovery rate of pure electric garbage trucks and ensure the braking effect of garbage trucks, a strategy of optimizing the regenerative braking fuzzy control of garbage trucks by particle swarm optimization is proposed. A multi-stage front and rear wheel braking force distribution curve considering braking effect and braking energy recovery is designed. According to the vehicle demand braking force and braking strength, a hierarchical regenerative braking fuzzy control strategy is established. The first layer is based on the vehicle demand braking force, based on the front and rear axle braking force distribution scheme, and uses the fuzzy controller to realize the first distribution of the front axle braking force.
Technical Paper

Numerical Evaluation of Injection Parameters on Transient Heat Flux and Temperature Distribution of a Heavy-duty Diesel Engine Piston

2024-04-09
2024-01-2688
A major concern for a high-power density, heavy-duty engine is the durability of its components, which are subjected to high thermal loads from combustion. The thermal loads from combustion are unsteady and exhibit strong spatial gradients. Experimental techniques to characterize these thermal loads at high load conditions on a moving component such as the piston are challenging and expensive due to mechanical limitations. High performance computing has improved the capability of numerical techniques to predict these thermal loads with considerable accuracy. High-fidelity simulation techniques such as three-dimensional computational fluid dynamics and finite element thermal analysis were coupled offline and iterated by exchanging boundary conditions to predict the crank angle-resolved convective heat flux and surface temperature distribution on the piston of a heavy-duty diesel engine.
Technical Paper

A methodology of modeling the thermal behavior of an electric axle in real driving cycles

2024-04-09
2024-01-2588
The thermal behavior of the electric axle is an essential indicator which requires certain attention during the development process. Due to the complexity of heat generation mechanism and heat transfer boundary conditions, it is difficult to accurately predict the axle’s temperature, especially in real driving conditions. In this paper, a comprehensive 1D model is developed to simulate its heat transfer process effectively and accurately. The heat transfer model is developed based on the thermal network method, and the electric axle is divided into thermal mass according to its heat transfer characteristics. The heat generation model, which accounts for meshing loss, bearing loss, churning loss, and winding loss, exchanges heat flux and temperature information with the heat transfer model to take into account the effect of lubricating oil temperature on power loss.
Technical Paper

Quantifying uncertainty in bicycle-computer position measurements

2024-04-09
2024-01-2486
The goal of this study is to quantify the uncertainty in bicycle computer measurements of position and speed. We acquired 100+ hours of position and speed data at 1-second intervals simultaneously from three Garmin Edge 530 computers mounted to the same handlebars during road cycling in rural and urban environments. Based on these data, we generated probability distributions that quantify the following: i) the drift and uncertainty in the recorded position (based on GPS), and ii) the uncertainty in speeds recorded by three different methods (internally computed from GPS and two Garmin speed sensors). This study provides foundational information regarding the appropriate methods and data needed to quantify the uncertainty in bicycle-computer data and to probabilistically interpret these data for collision reconstruction purposes.
Technical Paper

Integrating Machine Learning in Pedestrian Forensics: A Comprehensive Tool for Analysing Pedestrian Collisions

2024-04-09
2024-01-2468
In 2022, 385 pedestrians were killed in Great Britain, whilst 5,901 were reported to be seriously injured. Although these rates have improved since 2004, they have worsened since 2020. Due to the nature of the interaction and the physics involved, these collisions are extremely complex. Analysis of these accidents becomes difficult due to restricted access to cameras and vehicle data, as well as limited investigation techniques, which are frequently based on the Searle throw distance estimate. The current forensic methods usually require lengthy investigations and focus mainly on determining the vehicle’s impact speed to ascertain the driver’s degree of liability. Current accident reconstruction methods cannot reliably calculate the pedestrian kinematics behaviour at the time of impact, nor are they capable of solving hit-and-run scenarios without relying on additional evidence, which this research addresses.
Technical Paper

Investigation of Truck Tire Rubber Material Definitions Using Finite Element Analysis

2024-04-09
2024-01-2648
This paper investigates the tire-terrain interaction for a Mixed Service Drive (MSD) truck tire with two different solid rubber material definitions using a Finite Element Analysis (FEA) virtual environment. An MSD truck tire sized 315/80R22.5 is designed with two different solid rubber material definitions: a legacy Hyperelastic Solid Mooney-Rivlin material definition and an Ogden Visco-Hyperelastic solid material definition. The popular Mooney-Rivlin is a material definition for solid rubber simulation that is not built with element elimination and is not easily applicable for thermal applications. The Ogden Visco-Hyperelastic material definition for rubber simulations allows for element destruction and is more suited for designing tire wear models. Both the Mooney-Rivlin and Ogden-equipped MSD truck tires are subjected to a static vertical stiffness test to validate their static domain characteristics.
Technical Paper

Frontal crash oriented robust optimization of the electric bus body frame considering tolerance design

2024-04-09
2024-01-2459
For the design optimization of the electric bus body frame orienting frontal crash, considering the uncertainties may impact the crashworthiness performance, a robust optimization scheme considering tolerance design is proposed, which maps the given acceptable objective and feasibility variations into the parameter space to analyze the robustness. Two contribution analysis methods those are the entropy weight and TOPSIS method and the grey correlation calculations method are adopted to screen all the design variables, and 15 shape design variables with relatively high effect are chosen for design optimization. A symmetric tolerance and interval model is used to describe the uncertainty of 15 shape design variables of the key components of the bus body skeleton 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 simultaneously.
Technical Paper

Development of simulation methodology to evaluate Leaf Spring strength and predict the Leaf Interface stresses and correlating with test

2024-04-09
2024-01-2735
Leaf Springs are commonly used as a suspension in heavy commercial vehicle for higher load carrying capacity. The leaf springs connects the vehicle body with road profile through axle & tire assembly. It provides the relative motion between the vehicle body and road profile for improving the ride & handling performance. The leaf springs are designed to provide the linear stiffness and uniform strength characteristics throughout its travel. Leaf springs are generally subjected to dynamic loads which are induced due to different loads & driving patterns. Leaf spring design should be robust as any failure in leaf springs will put vehicle safety at risk and cost the vehicle manufacturer reputation. The design of a leaf spring based on the conventional methods predicts the higher stress levels at the leaf spring center clamp location and stress levels gradually reduce from the center to free ends of the leaf spring.
Technical Paper

Addition of Tire Forces into Low-speed Bumper-to-Bumper Crash Reconstruction Simulation Models

2024-04-09
2024-01-2479
Reconstruction of inline crashes between vehicles with a low closing speed, so-called “low speed” crashes, continues to be a class of vehicle collisions that reconstructionists require specific methods to handle. In general, these collisions tend to be difficult to reconstruct due primarily to the lack of, or limited amount of, physical evidence available after the crash. Traditional reconstruction methods such as impulse-momentum (non-residual damage based) and CRASH3 (residual damage based) both are formulated without considering tire forces of the vehicles. These forces can be important in this class of collisions. An alternative stiffness-based method for low closing speed crashes has been developed [1]. This method characterizes the stiffness of vehicle pairs using data from tests with exemplars of the subject vehicles. As currently formulated, the method does not include the effects of tire forces.
Technical Paper

Simulation Methodology for Failure Analysis of Catalytic Converter Mounting on Commercial Vehicles

2024-04-09
2024-01-2247
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 engine and hence the durability of the product is significantly impacted.
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