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This research provides a capacitance based method for monitoring the integrity of tires and other polymeric products during manufacturing and throughout the useful product life. Tire and wheel failures and tire degradation were the reported cause for approximately 19320 vehicle crashes over a two and a half year period according to the U.S. Department of Transportation National Highway Traffic Safety Administration's 2008 survey. Tires are complex composite structures composed of layers of formulated cross-linked rubber, textiles, and steel reinforcement layers. Tire production requires precise manufacturing through chemical and mechanical methods to achieve secure attachment of all layers. Tires are subjected to a variety of harsh environments, experience heavy loads, intense wear, heat, and in many cases lack of maintenance. These conditions make tires extremely susceptible to damage.

A low-cost hydrostatic absorption dynamometer has been developed for small to medium sized engines. The dynamometer was designed and built by students to support student projects and educational activities. The availability of such a dynamometer permits engine break-in cycles, performance testing, and laboratory instruction in the areas of engines, fuels, sensors, and data acquisition. The dynamometer, capable of loading engines up to 60kW at 155Nm and 3600rpm, incorporates a two-section gear pump and an electronically operated proportional pressure control valve to develop and control the load. A bypass valve permits the use of only one pump section, allowing increased fidelity of load control at lower torque levels. Torque is measured directly on the drive shaft with a strain gage. Torque and speed signals are transmitted by an inductively-powered collar mounted to the dynamometer drive shaft. Pressure transducers at the pump inlet and pump outlet allow secondary load measurement.

Fixed-displacement pump, variable-displacement motor configurations are rarely utilized for hydrostatic transmission designs, but they can achieve several advantages over more traditional systems. Developing a hydraulic drivetrain to accomplish high efficiency at high torque is often difficult because variable-displacement pumps are less efficient at low displacements. However, a system that utilizes modern electro-hydraulic valves and an electrically controlled variable-displacement hydraulic motor is easy to modulate and achieves its peak efficiency at low speeds. During the 2005 ASABE (American Society of Agricultural and Biological Engineers) ¼ Scale Tractor Student Design Competition, one such system was compared to conventional hydrostats and belt driven continuously variable transmissions. The fixed pump, variable motor system proved to be easy to operate. An electronic controller was used to modulate motor displacement to maintain constant engine speed.