9531504 Story This Small Business Innovation Research Phase II project is to design, develop, construct and evaluate a prototype surface acoustic wave (SAW) dew point hygrometer based on the Phase I research that will be lower in cost and have several advantages over existing optical dew point instruments. The advantages include a cost of about half that of existing optical dew point hygrometers, higher resolution and accuracy, reduced sensitivity to contamination, frost point transition detection, and stability through the frost point. Cost and performance improvements in dew point instrumentation are important in the fields of atmospheric sciences, agriculture, and numerous industries. Four main objectives are planned for the Phase II work. They include: dew point measurement research which involves investigating the stability and robustness of the control algorithm for frost point measurements during frost point transition, and the effects of SAW substrate microroughness and surface coatings on dew point measurement accuracy; The design and construction of the prototype instrument which involves RF oscillator design, design of the microprocessor based control unit, and packaging of the prototype instrument; Testing, evaluation, and calibration of the prototype instrument; Analysis of testing and evaluation. Corresponding design improvements will be made to the prototype based on this analysis. This work is expected to produce a prototype for manufacturing. Low cost and accurate dew point hygrometers have many commercial applications. The need is especially strong in the areas of meteorology, climatology, agriculture and industries such as microelectronics, chemical, food, steel, and paper. For example, studies of atmospheric water vapor concentrations and humidity content of industrial process gases.
