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The 31 papers in this technical paper collection detail sustainability; vehicle solutions and technologies for freight efficiency; human factors in occupant safety; machine health and conditioned based maintenance; aerodynamic and fuel economy assessment methods and techniques; and service issues.

"Spotlight on Design" features video interviews and case study segments, focusing on the latest technology breakthroughs. Viewers are virtually taken to labs and research centers to learn how design engineers are enhancing product performance/reliability, reducing cost, improving quality, safety or environmental impact, and achieving regulatory compliance. Just how prevalent is the problem of counterfeit electronic parts? What are the consequences of using sub-par components in safety or mission critical systems? The Federal Aviation Administration estimates that 2% of the 26 million airline parts installed each year are counterfeit, accounting for more than 520,000 units, maybe more.

The 9-meter wind tunnel of the National Research Council (NRC) of Canada is equipped with a boundary layer suction system, center belt and wheel rollers to simulate ground motion relative to test articles. Although these systems were originally commissioned for testing of full-scale automotive models, they are appropriately sized for ground simulation with half-scale tractor-trailer combinations. The size of the tunnel presents an opportunity to test half-scale commercial vehicles at full-scale Reynolds numbers with a model that occupies 3% of the test section cross-sectional area. This study looks at the effects of ground simulation on the force and pressure data of a half-scale model with rotating tractor wheels. A series of model changes, typical of a drag reduction program, were undertaken and each configuration was tested with both a fixed floor and with full-ground simulation to evaluate the effects of this technology on the total and incremental drag coefficients.

This paper reviews the correlation concepts and tools available, with the emphasis on their historical origins, mathematical properties and applications. Two of the most commonly used statistical correlation indicators, i.e., modal assurance criterion (MAC) for structural deformation pattern identification/correlation and the coefficient of determination (R2) for data correlation are investigated. The mathematical structure of R2 is critically examined, and the physical meanings and their implications are discussed. Based on the insights gained from these analyses, a data scatter measure and a dependency measure are proposed. The applications of the measures for both linear and nonlinear data are also discussed. Finally, several worked examples in vehicle dynamics analysis and statistical data analyses are provided to demonstrate the effectiveness of these concepts.

The impact of Reynolds number on the aerodynamics and operational performance of commercial vehicles is discussed. All supporting data has been obtained from published experimental and computational studies for complete vehicles and vehicle components. A review of Reynolds number effects on boundary layer state, unsteady and steady flow, time dependent wake structure, interacting shear layer and separated flows is presented. Reynolds number modeling and simulation criteria that impact aerodynamic characteristics and performance of a commercial vehicle are shown. The concepts of dimensional analysis and flow similarity are employed to show that aerodynamics of commercial ground vehicles is only dependent on Reynolds number. The terminology of Roshko is adopted for discussing the variation in drag with Reynolds number in which the subcritical, transitional and transcritical flow regimes are defined for commercial vehicles.

This document establishes the requirements for technical content and format of hydraulic system diagrams. This document does not establish configuration requirements, material, or performance requirements for any system or component identified herein.

This SAE Standard applies to machines as defined in Appendix A. Some of these machines can travel on-highway, but function primarily off-highway.

This SAE Standard applies to machines as defined in Appendix A. Some of these machines can travel on-highway, but function primarily off-highway.

We studied the effect of steering dynamics on lateral dynamics for a 1.6 ton 4x4 sport utility vehicle (SUV) on deformable surfaces. The vehicle used for the outdoor tests was equipped with (1) a steering robot to apply repeatable steering wheel excitations and (2) a high-precision differential GPS (DGPS) system to gather physical measures that describe lateral dynamics: lateral acceleration, yaw rate, and vehicle sideslip angle. The vehicle was driven over three different deformable surfaces~a loess and a sandy soil and wet snow~with a constant speed of 10 km/h. The steering robot applied inputs of (1) sine wave excitation at 0.5, 1.0, and 2.5 Hz, and (2) ramp change (or trapezoidal) excitation with steering wheel rate at 100, 500, and 1500 deg/s. Results are presented as frequency paths and time courses to analyze effects of surface and steering dynamics.

This study attempts to predict the effect of visual impairment from simulated levels of splash and spray on target vehicle identification distances. Five levels of hand held spray simulation frames were used to compare image digitization methods with visual performance (Snellen acuity or contrast sensitivity) assessment to predict a drivers ability to identify an oncoming target vehicle. The image digitization process was found to be highly correlated with actual target vehicle identification distances. Additionally, very high correlations were found between Snellen acuity and contrast sensitivity and identification distance. There did not seem to be any great difference in predictive power of either method of visual performance assessment over the other.

The feasibility study of using machine vision technology to locate corn plants was conducted to determine its potential in the development of an intelligent detasseling machine. A corn plant feature, the main vein of leaf, was used and the method of feature detection was developed for corn plant identification. Experimental results showed that the leaf feature and the center of the plant can be detected and located using image processing techniques when an image is taken from above of a plant. This research showed that it is possible to identify and locate the corn plant using machine vision technology.

The road impact load and the vibration are the main factors for the commercial vehicle, especially on the van trailer. In this paper, a new method which puts the operating modal identification and power spectrum density (PSD) analysis together was presented. The analysis results coincided with the road test quite well. The power spectrum response was obtained and the fatigue life of the vehicle was also estimated. This method can be used for the vibration optimization design and a random fatigue design of other commercial vehicles.

This paper reviews the basics of radio frequency identification technology and the existing uses in commercial vehicle systems. The specific engineering design challenges associated with the metallic environments encountered in commercial applications are discussed. An empirical design method using a variable dielectric thickness is given. Experimental results for the use of RFID in the metallic environment encountered in a commercial vehicle demonstrate the validity of the design method.

Abstract Aiming at the problem of low recognition rate and slow speed caused by the small proportion of key area information in feature vectors of original Pyramid Histogram of Gradients (PHOG) features, an improved feature extraction method of PHOG is proposed. The PHOG feature extraction method is combined with edge feature enhancement method based on Census transform to extract feature vectors of fasteners, and dimensionality reduction is processed by Kernel Principal Component Analysis (KPCA) method to reduce the interference of redundant information. The vector is inputted into the support vector machine for training in order to get the classifier model and realize the automatic identification of the fastener’s state. The simulation results show that compared with the traditional PHOG method, this feature extraction method improves the false detection rate by 2.7%, and the complexity of the algorithm is greatly reduced.

This SAE Standard applies to future designs of self-propelled, rubber-tired loaders, tractors, graders, backhoe loaders, tractor-scrapers, excavators, and dumpers as defined in SAE J1057 JUN81.