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Wind tunnel aerodynamic testing involving rolling road tire conditions can be expensive and complex to set up. Low cost rolling road testing can be implemented in a 0.3m2 Eiffel wind tunnel by modifying a horizontal belt sander to function as a moving road. This sander is equipped with steel supports to hold a steel plate against the bottom of the wind tunnel to stabilize the entire test section. These supports are bolted directly into the sander frame to ensure minimal vibrational losses or errors during testing. The wind tunnel design at the beginning of the project was encased in a wooden box which was removed to allow easier access to the test section for installation of the rolling road assembly. The tunnel was also modified to allow observers to view the testing process from various angles.

Published information on studies of something so critical to safety as passenger vehicle tire pressures can be found [1, 2]; however, they only account for rolling tires. Studies related to spare tire pressures are lacking. This paper is the result of measurements on 150+ vehicles and the most surprising results are presented regarding the influence of Tire Pressure Monitoring Systems (TPMS) and the new spare tire locations and use. A statistical study was performed on the collected data to determine the correlation between tire pressures, vehicle age and TPMS. One particular topic of investigation was the relationship between various factors that influence spare tire pressure. Some newer models, particularly some mini-vans, have placed the spare tire in an unusual and inconvenient place for regular maintenance. Based on the data collected, TPMS has a positive influence on rolling tires but not on spare tires. The results support the need for TPMS to also monitor spare tire pressures.

Water tunnels are used for a variety of research purposes including hydrodynamic and aerodynamic studies. In order to meet the technical needs of the research topics, a water tunnel with a one square meter cross section has been designed to reach one meter per second flow rates in a continuous flow environment. The primary mode for achieving this Re = 106 system is an extremely high flow rate pump combined with an ultra high efficiency flow path. The tunnel will weigh over 24,000 kg and will have a test velocity of 1 m/s. The tunnel is under construction in the University of North Carolina at Charlotte Motorsports Research facility and the expectation is that it will be operational in January of 2009.

Most commercial heavy-duty truck trailers are equipped with either a two sensor, one modulator (2S1M) or four sensors, two modulator (4S2M) anti-lock braking system (ABS). Previous research has been performed comparing the performance of different ABS modules, in areas such as longitudinal and lateral stability, and stopping distance. This study focuses on relating ABS module type and wheel speed sensor placement to trailer wheel lock-up and subsequent impact to tire wear for tandem axle trailers with the Hendrickson air-ride suspension. Prior to tire wear inspection, functionality of the ABS system was testing using an ABS scan tool communicating with the SAE J1587 plug access port on the trailer. Observations were documented on trailers using the 2S1M system with the wheel speed sensor placed on either the front or rear axle of a tandem pair.

A warning system is described as, that improves safety in an over the road truck application by warning the driver with steering wheel vibration of impending roll over. This work focuses on creating a Haptic feedback and the corresponding driver response to a range of frequencies and amplitudes of vibration at the steering wheel. The haptic feedback system is the endpoint of the entire warning system. An experimental road going system is designed, presented, and tested. The experimental data reveals information about the response of the human subject to the frequency of steering wheel vibration, while driving a vehicle. Data variability is investigated through sampling of a population of drivers. The experimental setup probing the amplitude and frequency information is analyzed. Objective measurement anomalies in the data were seen in the subjective tests as well. Some conclusions are given about the applicability of laboratory tests to moving vehicle tests.

There have been claims that the rear wing on the NASCAR Car of Tomorrow (COT) race car causes lift in the condition where the car spins during a crash and is traveling backwards down the track at high speed [1,2]. When enough lift is generated, the race car can lose control and even become airborne. At least in part, to address this concern, a new rear spoiler was designed by NASCAR to replace the wing and prevent this dangerous condition. This paper looks at the flow characteristics of both the rear wing and the new spoiler using particle image velocimetry (PIV) to provide qualitative analysis as well as flow visualization. In particular, the interaction of these downforce devices with "roof flaps" (which are designed to prevent lift) is explored. These experiments are done in a continuous flow water tunnel having a cross section of 1.0 m2 using a simplified 10% scale model COT body with either a wing or spoiler attached.

This research is in regards to the development of an inexpensive anti-rollover system for use in the trailer axles of a heavy commercial truck. It includes the design and experimental results for a real-time rollover warning system to inform the driver prior to rollover or to initiate stability control algorithms in the vehicle. The developed system in this research uses suspension displacement, lateral acceleration, and wheel speed measurements. These are used to continuously update the calculation of centre of gravity (CG) height which is compared to the lateral acceleration to determine the proximity of rollover.

This paper is part of a bigger research effort that aims to capture the influences of static wheel alignment measurement accuracy for road going vehicles. Vehicle alignments can and often are the bottleneck in automotive and truck assembly lines and a greater understanding of the issues are very valuable. The alignment equipment in this research has been tuned and adjusted to minimize external variables and the team of authors have 300+ vehicle measurements. Of the many things that influence the accuracy and repeatability of vehicle suspension alignment measurement and adjustment, the measurement procedures can be the most significant. This includes but is not limited to alignment machine setup and vehicle tire pressures.

A high accuracy and low cost test protocol for the determination of the inertial characteristics of a high performance vehicle transmission is discussed. In particular, a range of NASCAR Sprint Cup race car transmission gear packages are tested and compared. The test results compare the inertial characteristics from the new CR2C transmission as developed by C&R Racing to the current standard four-speed manual version. The test protocol evaluates the inertial properties by suspending the input, output, and secondary shafts from a light weight hollow Ø1/4" x 16.58' long (Ø6.35 mm x 5.05 m) vertical torsion spring tube. An initial offset twist results in rotational cycling of the components at an easily measurable natural oscillatory period. The equations are developed for the application of the natural frequency measurements to the component inertia results.