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As an annual subscription, the Wiley Cyber Security Collection Add-On is available for purchase along with one or both of the following: Wiley Aerospace Collection Wiley Automotive Collection The titles from the Wiley Cyber Security Collection are included in the SAE MOBILUS® eBook Package. Titles: Network Forensics Penetration Testing Essentials Security in Fixed and Wireless Networks, 2nd Edition The Network Security Test Lab: A Step-by-Step Guide Risk Centric Threat Modeling: Process for Attack Simulation and Threat Analysis Applied Cryptography: Protocols, Algorithms and Source Code in C, 20th Anniversary Edition Computer Security Handbook, Set, 6th Edition Threat Modeling: Designing for Security Other available Wiley collections: Wiley SAE MOBILUS eBook Package Wiley Aerospace Collection Wiley Automotive Collection Wiley Computer Systems Collection Add-On (purchasable with the Wiley Aerospace Collection and/or the Wiley Automotive Collection)

This technical paper collection discusses the modeling, analysis, and validation of commercial vehicle chassis, suspension, and tire modeling and simulation. Topics include commercial vehicle dynamics; chassis control devices such as ABS, traction control, yaw/roll stability control, and their interaction with suspension controls; modeling and simulation of ride comfort, as well as passive and active suspension control methodologies. Authors are encouraged to discuss the validation of their modeling and simulation.

Abstract Dynamic stresses exist in parts of a catalyst muffler caused by the vibration of a moving vehicle, and it is important to clarify and predict the vibration response properties for preventing fatigue failures. Assuming a vibration isolating installation in the vehicle frame, the vibration transmissibility and local dynamic stress of the catalyst muffler were examined through a vibration machine. Based on the measured data and by systematically taking vibration theories into consideration, a new prediction method of the vibration modes and parameters was proposed that takes account of vibration isolating and damping. A lumped vibration model with the six-element and one mass point was set up, and the vibration response parameters were analyzed accurately from equations of motion. In the vibration test, resonance peaks from the hanging bracket, rubber bush, and muffler parts were confirmed in three excitation drives, and local stress peaks were coordinate with them as well.

Abstract Vehicle rolling resistance and weight are two of the factors that affect fuel economy. The vehicle tire rolling resistance has a more significant influence than aerodynamics drags on fuel economy at lower vehicle speeds, particularly true for medium- and heavy-duty trucks. Less vehicle weight reduces inertia loads, uphill grade resistance, and rolling resistance. The influence of weight on the fuel economy can be considerable particularly in light- to medium-duty truck classes because the weight makes up a larger portion of gross vehicle weight. This article presents an empirical investigation and a numerical analysis of the influences of rolling resistance and weight on the fuel economy of medium-duty trucks. The experimental tests include various tires and payloads applied on a total of 21vehicle configurations over three road profiles. These tests are used to assess the sensitivity of rolling resistance and weight to the vehicle fuel economy.

Abstract An accurate and rapid thermal model of an axle-brake system is crucial to the design process of reliable braking systems. Proper thermal management is necessary to avoid damaging effects, such as brake fade, thermal cracking, and lubricating oil degradation. In order to understand the thermal effects inside of a lubricated braking system, it is common to use Computational Fluid Dynamics (CFD) to calculate the heat generation and rejection. However, this is a difficult and time-consuming process, especially when trying to optimize a braking system. This article uses the results from several CFD runs to train a Stacked Ensemble Model (SEM), which allows the use of machine learning (ML) to predict the systems’ temperature based on several input design parameters. The robustness of the SEM was evaluated using uncertainty quantification.

Abstract This study proposes a method for the rapid detection and location of cavity defects in ballastless track structures of high-speed railways in service. First, the propagation law of air-coupled ultrasonic Lamb waves in the ballastless track structure is studied. Theoretical calculation results show that the ultrasonic Lamb wave group velocity of the A2 mode in the track plate is 4000 m/s. Then, the excitation and reception methods of the air-coupled ultrasound are studied. Theoretical and experimental results show that the A2 mode Lamb wave can be generated by the 3.8° oblique incidence of the ballastless track structure. Finally, an experimental system for air-coupled ultrasonic testing is constructed. A pair of air-coupled ultrasonic probes is used to provide excitation and reception Lamb wave signals at an inclined angle of 3.8°, 20 mm away from the surface of the track plate, and 40 mm/step along the scanning direction.

Abstract To gain a better understanding of the characteristics of corrugation, including the development and propagation of corrugation, and impact of vehicle and track dynamics, a computational model was established, taking into account the nonlinearity of vehicle-track coupling. The model assumes a fixed train speed of 300 km/h and accounts for vertical interaction force components and rail wear effect. Site measurements were used to validate the numerical model. Computational results show that (1) Wheel polygonalisation corresponding to excitation frequency of 545-572 Hz was mainly attributed to track irregularity and uneven stiffness of under-rail supports, which in turn leads to vibration modes of the bogie and axle system in the frequency range of 500-600 Hz, aggregating wheel wear. (2) The peak response frequency of rail of the non-ballasted track coincides with the excitation frequency of wheel-rail coupling; the resonance results in larger wear amplitude of the rail.

The objective of the project was to conduct controlled test-track studies of solutions for achieving higher fuel efficiency and lower greenhouse gas emissions in the trucking industry. Using vehicles from five Canadian fleets, technologies from 12 suppliers were chosen for testing, including aerodynamic devices and low rolling resistance tires. The participating fleets also decided to conduct tests for evaluating the impact on fuel consumption of vehicle speed, close-following between vehicles, and lifting trailer axles on unloaded B-trains. Other tests targeted comparisons between trans-container road-trains and van semi-trailers road-trains, between curtain-sided semi-trailers, trans-containers and van semi-trailers, and between tractors pulling logging semi-trailers loaded with tree-length wood and short wood. The impact of a heavy-duty bumper on fuel consumption and the influence of B5 biodiesel blend on fuel consumption were also assessed.

The objective of this project was to compare the fuel consumption and traction performances of 6 × 2 and 6 × 4 Class 8 tractors. Two approaches have been considered: evaluation of 6 × 2 tractors, modified from 6 × 4 tractors, and evaluation of OEM 6 × 2 tractors. Compared to the 6 × 4 tractors, which are equipped with a rear tandem with both drive axles, the 6 × 2 tractors have a rear tandem axle with one drive axle, and one non-drive axle, also called dead axle. The 6 × 2 tractor configurations are available from the majority of Class 8 tractor manufacturers. The SAE Fuel Consumption Test Procedures Type II (J1321) and Type III (J1526) were used for fuel consumption track test evaluations. Traction performances were assessed using pull sled tests to compare pulling distance, maximum speed, and acceleration when pulling the same set sled on similar surface.

Coatings have the potential to improve bearing tribological performance. However, every coating application process and material combination may create different residual stresses and coating microstructures, and their effect on bearing fatigue and wear performance is unclear. The aim of this work is to investigate coating induced residual stress effects on bearing failure indicators using a microstructural contact mechanics (MSCM) finite element (FE) model. The MSCM FE model consists of a two-dimensional FE model of a coated bearing surface under sliding contact where individual grains are represented by FE domains. Interactions between FE domains are represented using contact element pairs. Unique to this layered rolling contact FE model is the use of polycrystalline material models to represent realistic bearing and coating microstructural behavior. The MSCM FE model was compared to a second non-microstructural contact mechanics (non-MSCM) model.

Comparison studies have been conducted on a 1:16th scale model and a full scale tractor trailer of a variety of sealed aft cavity devices as a means to develop or enhance commercial drag reduction technology for class 8 vehicles. Various base cavity geometries with pressure taps were created for the scale model. The studies confirmed that length has an important effect on performance. The interaction of the boat-tailed aft cavity with other drag reduction devices, specifically side skirts, was investigated with results showing no discernable drag performance interaction between them. Overall, the experiments show that a boat-tailed aft cavity can reduce the drag up to 13%. Full-scale tests of a commercially derived product based on these scale tests were also completed using SAE Type II testing procedures. Full-scale tests indicated a fuel savings of over 6.5%.

A new approach for detecting problems with vehicle brakes by analyzing sounds emitted during braking events is proposed. Vehicle brakes emit acoustic energy as part of the braking process; the spectra of these sounds are highly dependent on the mechanical condition of the brake and can be used to detect problems. Acoustic theory indicates that as brake linings wear thinner the resonant frequency of the shoe or pad increases, potentially enabling the monitoring of lining wear through passive acoustic sensors. To test this approach, passive acoustic sensors were placed roadside at the exit of a transit bus facility for 9 months. The sensors collected almost 10,000 recordings of a fleet of 160 vehicles braking over a variety of conditions. Spectra of vehicles that had brake work performed during this period were analyzed to compare differences between new and worn friction linings.

This paper discusses the test setup and methodology required to validate complete lift axle assembly for simulating the real time test track data. The correlation of rig vs track is discussed. The approach for reduction of validation time by eliminating few of the non-damaging tracks/events, its correlation with real life condition is discussed, and details are presented. With increased competition, vehicle development time has reduced drastically in recent past. Bench test procedure using accelerated test cycle discussed in this paper will help to reduce development time and cost. Process briefed in this paper can also be used for similar test specification for other structural parts or complete suspension system of heavy commercial vehicles.

Bogie-type suspensions for trucks are comprised of two axles and a central spring pack on each side of the truck chassis. Bogie suspensions have a good load distribution between the axles and are used for severe applications in trucks, in off-road conditions thereby subjecting them to extreme stain and load. In today’s competitive market scenario, it of utmost importance to minimize down time in commercial vehicles as it directly corresponds to loss in business which leads to customer dissatisfaction. It is therefore essential to optimize and select the right material for each component in the bogie suspension system. This paper deals with the material selection and testing of one such component - Bogie Wear Pad. The bogie wear pad undergoes sliding friction throughout its lifetime during loading and unloading of bogie suspension. Three different materials are selected and their wear is measured under the same conditions of loading.

Access method design for entry and egress of medium and heavy duty truck cabs and bodies is a critical aspect of vehicle design. Occupational injuries due to entering or exiting the truck cab, or climbing onto and off of the truck body, can be a significant percentage of a fleet's lost-time incident rate. Many vocational trucks operate in both off-road and on-road conditions, and the slip resistance of the stepping surface is an important design aspect. Examples of vocational vehicles that involve off-road operation include dump, refuse, utility, tree-trimming, and concrete trucks. Stepping surfaces in these applications must provide a balance between traction and the ability to shed water, snow, and mud. While there are a few methods and devices for measuring walking surface slip resistance, they are either complicated, or not well suited to measuring aggressive surfaces.

The winter of 2013-2014 provided an opportunity to operate off-road vehicles in cold weather for extended time as part of a vehicle/tier 4 diesel engine validation program. An unexpected area of study was the performance of high efficiency, on engine, fuel filters during continuous vehicle operation in cold weather. During the program we observed unexpected premature fuel filter plugging as indicated by an increase in pressure drop across the filter while in service. Field and laboratory testing was completed at John Deere and Donaldson to understand the cause of filter plugging. Although conditions were found where winter fuel additives could cause plugging of high efficiency filters, premature filter plugging occurred even when testing with #1 diesel fuel. This fuel contained no additives and was used at temperatures well above its cloud point.

Using lift axles enables fleet to increase the load capacity of a vehicle, eliminating the need for multiple trips, thus reducing operational costs. In a project to assess the potential of reducing fuel consumption and greenhouse gas (GHG) emissions by lifting axles on unloaded semi-trailers, lift axle regulations in various jurisdictions and the studies that led to these regulations were analyzed. The SAE Fuel Consumption Test Procedures Type II (J1321) was used for fuel consumption track test evaluations. The tests were conducted on unloaded two-axle van semi-trailers, four-axle van semitrailers, and B-trains, and resulted in fuel savings of 1.3% to 4.8%, depending on vehicle configuration and the number of axles lifted during the test.

The performance of several aerodynamic technologies and approaches, such as trailer skirts, trailer boat tails, gap reduction, was evaluated using track testing, model wind tunnel testing, and CFD simulation, in order to assess the influence of the design, position and combination of various aerodynamic devices. The track test procedure followed the SAE J1321 SAE Fuel Consumption Test Procedure - Type II. Scale model wind tunnel tests were conducted to have direct performance comparisons among several possible configurations. The wind tunnel tests were conducted on a 1/8 scale model of a tractor in combination with a 53-foot semi-trailer. Among others, the wind tunnel tests and CFD simulations confirmed the influences of trailer skirts' length observed during the track tests and that the wider skirt closer to the ground offer better results. The differences in the shape, dimensions and position of rear deflectors and trailer skirts on the trailer are reflected in the test results.

For applying ISO 26262 to motorcycles, controllability classification (C class evaluation) by expert riders is considered an appropriate technique. Expert riders have evaluated commercial product development for years and can appropriately conduct vehicle tests while observing safety restrictions (such as avoiding the risk of falling). Moreover, expert riders can ride safely and can stably evaluate motorcycle performance even if the test conditions are close to the limits of vehicle performance. This study aims to construct a motorcycle C class evaluation method based on an expert rider’s subjective evaluation. On the premise that expert riders can rate the C class, we improved a test procedure that used a subjective evaluation sheet as the concrete C class evaluation method for an actual hazardous event.

The rapid innovation underway with vehicle brake safety systems leads to extensive evaluation and testing by system developers and regulatory agencies. The ability to evaluate complex heavy truck braking systems is potentially more rapid and economical through hardware-in-the-loop (HiL) simulation which employs the actual electronics and vehicle hardware. Though the initial HiL system development is time consuming and expensive, tests conducted on the completed system do not require track time, fuel, vehicle maintenance, or technician labor for driving or truck configuration changes. Truck and trailer configuration and loading as well as test scenarios can be rapidly adjusted within the vehicle dynamics simulation software to evaluate the performance of automated safety interventions (such as ESC) over a wide range of conditions.