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Patents granted recently to Mr. Rode have changed the industry capability to adjust and verify wheel-end bearings on trucks. Until now it was believed1 that there was nothing available to confirm or verify the most desirable settings of preload on these bearings. The new, breakthrough invention is a tool and spindle-locking nut that permit quick and accurate wheel bearing adjustment by utilizing direct reading force measurement. Bearings can be set to either SAE recommended preloads or specific endplay settings. The author has been working on bearing adjustment methods for industrial applications for over forty years, and considers these inventions to be his most important breakthrough for solving this elusive bearing adjustment problem. Consistent wheel bearing preload adjustment was not possible before, even though it was widely known to achieve the best wheel performance as noted in SAE specification J2535 and re-affirmed in 2006 by the SAE Truck and Bus Wheel Subcommittee.

A heavy truck wind tunnel test program is currently underway at the Langley Full Scale Tunnel (LFST). Seven passive drag reducing device configurations have been evaluated on a heavy truck model with the objective of understanding the practical limits to drag reduction achievable on a modern tractor trailer through add-on devices. The configurations tested include side skirts of varying length, a full gap seal, and tapered rear panels. All configurations were evaluated over a nominal 15 degree yaw sweep to establish wind averaged drag coefficients over a broad speed range using SAE J1252. The tests were conducted by first quantifying the benefit of each individual treatment and finally looking at the combined benefit of an ideal fully treated vehicle. Results show a maximum achievable gain in wind averaged drag coefficient (65 mph) of about 31 percent for the modern conventional-cab tractor-trailer.

This paper presents a simulation of the cooling airflow and surface temperatures of a midsize truck. The simulation uses full detailed geometry of the truck. Performance of the under-hood cooling airflow is analyzed and potential design changes leading to better cooling airflow are highlighted. Surface temperature over certain under-hood part is studied. Possible optimizations using various material and configurations are proposed. It is shown that the presented simulation approach provides valuable information to evaluate cooling system and thermal protection performance. Fast design iterations can be achieved using this approach.

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 research project was to compare B20 (20% biodiesel fuel) and ultra-low-sulfur (ULSD) diesel-fueled buses in terms of fuel economy, vehicle maintenance, engine performance, component wear, and lube oil performance. We examined 15 model year (MY) 2002 Gillig 40-foot transit buses equipped with MY 2002 Cummins ISM engines. The engines met 2004 U.S. emission standards and employed exhaust gas recirculation (EGR). For 18 months, eight of these buses operated exclusively on B20 and seven operated exclusively on ULSD. The B20 and ULSD study groups operated from different depots of the St. Louis (Missouri) Metro, with bus routes matched for duty cycle parity. The B20- and ULSD-fueled buses exhibited comparable fuel economy, reliability (as measured by miles between road calls), and total maintenance costs. Engine and fuel system maintenance costs were also the same for the two groups after correcting for the higher average mileage of the B20 group.

This paper describes the joint development by Tenneco and Pi Shurlok of a complete diesel engine aftertreatment system for controlling particulate matter emissions. The system consists of a DOC, DPF, sensors, controller and an exhaust fuel injection system to allow active DPF regeneration. The mechanical components were designed for flow uniformity, low backpressure and component durability. The overall package is intended as a complete PM control system solution for OEMs, which does not require any significant additions to the OEM's engine control strategies and minimizes integration complexity. Thus, to make it easier to adapt to different engine platforms, ranging from small off-road vehicle engines to large locomotive engines, model-based control algorithms were developed in preference to map-based controls.

Inferential sensing, as it relates to the equipment operator, can be viewed as human intuition [1]. The person operating the equipment can sense there is something wrong while their intuition tells them when and what needs troubleshooting and repair. Attempts have been made to implement this human intuition model to monitor a vehicle operation and detect abnormalities. In many approaches traditional sensors are added to the vehicle which increases cost, complexity, and another failure point. After years of developments and techniques, there are few highly reliable on-board systems that can duplicate the human intuition model since the specific failure cannot be directly measured but must be inferred from a variety of symptoms. This paper describes an engineering approach using Physics of Failure (PoF) for specific subsystems, developing the applicable fatigue models, and then collecting, monitoring, and manipulating the real-time on-vehicle data to complement the “operator intuition”.

The timing and associated levels of braking between initial brake pedal application and actual maximum braking at the wheels for a tractor-semitrailer are important parameters in understanding vehicle performance and response. This paper presents detailed brake timing information obtained from full scale instrumented testing of a tractor-semitrailer under various conditions of load and speed. Brake timing at steer, drive and semitrailer brake positions is analyzed for each of the tested conditions. The study further seeks to compare the full scale test data to predicted response from detailed heavy truck computer vehicle dynamics simulation models available in commercial software packages in order to validate the model's brake timing parameters. The brake timing data was collected during several days of full scale instrumented testing of a tractor-semitrailer performed at the Transportation Research Center, in East Liberty, Ohio.

A driving simulator capable of duplicating the critical sensations incurred during a spin, or when a driver is engaged in drift cornering, was constructed by Mitsubishi Heavy Industries, Ltd., and Hiromichi Nozaki of Kogakuin University. Specifically, the simulator allows independent movement along three degrees of freedom and is capable of exhibiting extreme yaw and lateral acceleration behaviors. Utilizing this simulator, the control characteristics of drift cornering have become better understood. For example, after a J-turn behavior experiment involving yaw angle velocity at the moment when the drivers attention transitions to resuming straight ahead driving, it is now understood that there are major changes in driver behavior in circumstances when simulator motions are turned off, when only lateral acceleration motion is applied, when only yaw motion is applied, and when combined motions (yaw + lateral acceleration) are applied.

Model-Based Design with production code generation has been extensively utilized throughout the automotive software engineering community because of its ability to address complexity, productivity, and quality challenges. With new applications such as lane departure warning or electromechanical steering, engineers have begun to consider Model-Based Design to develop embedded software for applications that need to comply with safety standards such as IEC 61508. For in-vehicle applications, IEC 61508 is often considered state-of-the-art or generally accepted rules of technology (GART) for development of high-integrity software [6, 11]. In order to demonstrate standards compliance, the objectives and recommendations outlined in IEC 61508-3 [8] must be mapped onto processes and tools for Model-Based Design. This paper discusses a verification and validation workflow for developing in-vehicle software components which need to comply with IEC 61508-3 using Model-Based Design.

The last decades have shown extensive efforts on the investigation of automotive disk brake squeal. The origin of brake squeal is seen in self-excited vibrations, caused by the friction forces transferring energy from the rotating disk into the brake system. Based on a very simple model, Popp et al. described in 2002 the conditions for positive work of the friction forces (i.e. excitation of squeal), which depends on the phase shift between the in-plane motion (with respect to the disk) of the brake pad and the friction forces. Experiments on active manipulation of this phase shift using pads with integrated piezoceramic actuators, performed by von Wagner et al. in 2004, resulted in successful suppression of disk brake squeal. The authors of the present paper used a variety of models for the investigation of the origin of the excitation mechanism by observing phase relations between the friction forces and the vibrations of the pads.

Extenics is a new cross discipline to study rules and methods of solving contradictory problems in the real world. The basic concepts and theoretical frame of extenics are briefly introduced in this paper. Based on the merit of extenics, the extension evaluation method was applied to evaluate the brake materials according to a five-grade criterion established in this study. Considering the results computed by the original and simplified models, the similar conclusions were made: all four brake samples, marked A - D, were evaluated in the first grade based on the calculated dependence degrees, and sample B was judged as the best performing friction material with the highest dependence degree and the lowest wear rate.

This paper summarizes results from the author's work on friction in dry sliding contacts in the presence of vibration. A number of idealized models of smooth and rough contacts are examined. It is shown that vibration can cause up to a 10% reduction in average friction even with continuous contact. A larger reduction in friction occurs when there is intermittent contact loss. This is found to be true for both elastic and plastic contacts, and for adhesive and plowing mechanisms of friction. The results of this work are compared and validated with measurements from experiments. The results presented are fundamental, but applicable to machine components with contacts including brake systems.

This paper describes the principles of a new method to compensate for tool wear when drilling in complex materials such as Carbon Fibre Reinforced Plastics (CFRP), Carbon Fibre Reinforced Plastics / Titanium (CFRP/Ti) and Carbon Fibre Reinforced Plastics / Alloy (CFRP/AI) stacks. A reliable and repeatable hole quality is essential, especially in automatic drilling applications with robots or gantries. The method combines the unique feature to dynamically adjust the drilling diameter in very small steps in an Orbital drilling End-effector and a new type of software algorithm to predict and compensate for the tool wear in different materials. With this method a large number of holes can be drilled without changing the cutting tool, and a Cpk value of more than 2,5 can be achieved.

The presented paper introduces the new software complex aimed at simulation of the riveting process as applied to aircraft parts. The software complex implements the novel mathematical model based on minimization of the potential energy. The paper gives the detailed description of the mathematical model and particularizes the main features of the software. The physical and numerical tests aimed at validation of the software are also described in the paper.

Manual drilling and Lockbolt installation in carbon fiber structures is a labor intensive process. To reduce man hour requirements while concurrently improving throughput and process quality levels BROETJE-Automation developed a gantry positioning system with high performance multi-function end effectors for this application. This paper presents a unique solution featuring fully automated drilling and Lockbolt installation (inclusive of automated collar installation) for the vertical tail plane (vertical stabilizer) of large commercial aircraft. A flexible and reconfigurable assembly jig facilitates high access of the end effectors and increases the equipment efficiency. The described system fulfils the demand for affordable yet flexible precision manufacturing with the capacity to handle different aircraft model panels within the work envelope.

Due to the conventional autoclaving of pre-impregnated materials causes high costs in the production of carbon fibre structures, new injection methods have become more and more relevant. The research project “CFK-Tex” focuses on the automated handling and processing of preforms out of dry carbon fibre textiles. Regarding the advantages in quality improvement and process time, an automation of all process steps is getting enforced. The major challenge, in addition to the difficult handling-properties of the materials and high quality demands, is the enormous variety of outline variants caused by small production quantities but many different textile cuts per part. In the first step the requirements of an automated system are exactly analyzed considering the specific material properties as well as process and product based characteristics.

In this paper, the numerical analysis of a three-point bending test of an aluminum foam sandwich structure is performed with the new extended finite element feature supported by Abaqus 6.9. The sandwich beam consists of two aluminum skins and one aluminum foam core. Three different sets of model dimensions are selected for comparison with the reference results (J. Yu, E. Wang, J. Li, Z. Zheng, “Static and low-velocity impact behavior of sandwich beams with closed-cell aluminum-foam core in three-point bending”, International Journal of Impact Engineering, 35, 2008, pp 885-894). Failure modes in this paper can be categorized into three parts: face yield (FY), indentation (IN), and core shear (CS). Face yield occurs on the surface of the core when the thickness of the skin is small. Indentation and core shear occur if the thickness of the skin is relatively large.

The C-17 airplane operates in some of the most challenging environments in the world including semi prepared runway operations (SPRO). Typical semi-prepared runways are composed of a compacted soil aggregate of sand, silt, gravel, and rocks. When the airplane lands or takes off from a semi-prepared runway, debris, including sand, gravel, rocks and, mud is kicked up from the nose landing gear (NLG) and the main landing gear (MLG) tires. As the airplane accelerates to takeoff or decelerates from landing touchdown, this airborne debris impacts the underbelly and any component mounted on the underbelly. The result is the erosion of the protective surface coating and damage to systems that protrude below the fuselage into the debris path. The financial burden caused by SPRO damage is significant due to maintenance costs, spares costs and Non-Mission Capable (NMC) time.

The air traffic demand on the US national airspace frequently exceeds its available capacity. In current operations, the Air Traffic Service Provider designs and implements air traffic management initiatives with minimal interaction with the airlines. NASA and its partners have developed a new collaborative air traffic flow management concept of operations that involves the users of the airspace to a greater degree. In this paper, we describe an agent-based simulation of the new concept of operations and our planned experimentation to determine if the new concept of operations will lead to better utilization of the national airspace.