CREWES has been developing and improving its ultrasonic physical modelling facility. This modelling facility is capable of simulating seismic surveys in 3 dimensions over scaled down earth models composed of plastics and metals. Unlike prior physical modelling systems at the U of C, this one uses high precision linear motors with a 0.1 um optical measuring system to execute and measure the survey with great precision. In 2005, components for a new modelling system were purchased, and the new system was designed and major components were test-assembled. Progress has been made on three fronts: First, much of the necessary fabrication and assembly has been completed. Several hundred electrical connections have been wired, and a new circuit board was designed and assembled to indicate the status of the eight drive motors. Second, a series of programs have been written to intelligently operate the modelling system's drive motors based on a high-level seismic survey design. Simulation has proved useful in verifying correct operation of the software. Third, a change of source signal generation strategies has been proposed. By changing from an impulse source to a swept-frequency source we hope to improve the signal to noise ratio of physical modelling data. A numeric analysis of the swept-frequency source illustrates the benefit of this change.
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