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Window buffeting is a major source of flow induced sound and vibration. This paper will describe window buffeting measurements acquired on a full scale vehicle as well as two different simplified small scale models. The experimental data sets included microphone and phase averaged Particle Image Velocimetry (PIV) measurements both of which show that the flow physics are qualitatively and quantitatively similar in all cases. The implication of this result is that simplified laboratory models of a vehicle are sufficient to study the various aspects of window buffeting in full scale vehicles.

In the work leading to the TREAD Act, some members of Congress expressed the need for some type of aging test on light vehicle tires. Since no industry-wide recommended practice existed, the ASTM F09.30 Aged Tire Durability task group was established in 2002 to develop a test standard. During the first phase of development, it was found that the process of oxidative aging depleted the level of oxygen in some tires below the point at which aging could effectively continue. Therefore, in the second phase, a research module was formulated to determine the most appropriate method by which to maintain the oxygen concentration in the tire at a sufficiently high level. The research encompassed the evaluation of test data from laboratory aged tires whose oxygen concentration was kept elevated either through a top-off method or a vent/reinflate method. This presentation focuses on the analyses conducted to determine the appropriate method by which to maintain oxygen concentration in the tire.

In the work leading to the TREAD Act, some members of Congress expressed the need for some type of aging test on light vehicle tires. Since no industry-wide recommended practice existed, the ASTM F9.30 Aged Tire Durability task group was established in 2002 to develop a test standard. After several years of phase 1 research, the task group identified key learning about both static and dynamic laboratory aging. Accelerated aging conditions for both approaches were examined by statistically and empirically analyzing property changes of both field and laboratory aged tires relative to the corresponding properties of a new tire. The research encompassed the evaluation of test data from field tires that were directly compared and analyzed against the data generated from tires that were laboratory aged on an accelerated basis. This presentation focuses on the effects of static aging in an oven using a 4 variable statistical design of experiment.

During the first phase (Phase 1) of aged durability test development, static oven aging of tires was selected as the preferred method of accelerated laboratory aging. representative material property changes and warranted further study. The objective of this follow-up Phase 2 oven aging study was to identify preferred temperatures and times (or ranges) for the accelerated oven aging of tires, which could yield material property changes similar to those observed for in-service tires. These studies were conducted on three tire models. Conclusions and recommendations for subsequent validation across a broad spectrum of consumer tire types were reached.

In the work leading to the TREAD Act, some members of Congress expressed the need for some type of aging test on light vehicle tires. Since no industry-wide recommended practice existed, the ASTM F9.30 Aged Tire Durability task group was established in 2002 to develop a test standard. After several years of phase 1 research, the task group identified key learning about both static and dynamic laboratory aging. Accelerated aging conditions for both approaches were examined by statistically and empirically analyzing property changes of both field and laboratory aged tires relative to the corresponding properties of a new tire. The research encompassed the evaluation of test data from field tires that were directly compared and analyzed against the data generated from tires that were laboratory aged on an accelerated basis. This paper focuses on the effects of dynamic laboratory aging on a 1.7-meter roadwheel using a five variable statistical design.

This paper describes an embedded software solution to manage the various powertrain component and system diagnostics required for On-Board Diagnostics (OBDI and OBDII) regulatory compliance. It utilizes flexible configuration of the complex interactions between systems and components that would otherwise be very difficult to define early enough in the Engine Control Module (ECM) software process to meet lead-time requirements. This method for managing the OBD test routines and their interdependencies allows the interactions to be configured through the use of calibration tables after software verification testing has been completed. This results in higher reliability of productionized software by avoiding the need to have the interactions pre-defined and included in the software up-front, and by enabling configuration changes later in the process without affecting the software itself.

The development of a robust feedback slip controller for a torque converter clutch (TCC) is presented in this paper. The dynamic behavior of the TCC is modeled utilizing the principles of input-output system identification. An H∞ loop shaping controller design technique is applied in order to ensure robust stability against unmodeled system dynamics and large variations in system parameters. Road driving tests indicate that the control system achieves high levels of reliability and stability.