The research performed for this dissertation has been conducted with the goal of developing a ground convergence monitor that may better meet the needs of some mines, leading to increased use of ground monitoring programs and reduced fatality rates from falling and sliding rock. The developed monitor is a convergence monitor capable of achieving sensitivities similar to those of currently available convergence meters such as tape extensometers. The monitor is inexpensive and is capable of totally remote operation in some circumstances.;The monitor is a triangulation-based laser distance meter similar to those used in manufacturing and quality-control situations, though it is capable of ranges greatly exceeding those sensors currently available. It integrates a consumer digital camera, an inexpensive laser diode, a target, and custom-written computer software to track the convergence-driven movement of a laser spot across the target from image to image. The monitor was developed and components selected based on extensive experimentation and experiences in the laboratory and in the field.;A physical model of the meter was developed based on experimental results and compared to a derived theoretical model to show that the monitor was capable of accurately reproducing the predicted sensitivity values. The sensitivity was found to be dependent upon the width of the sensor imaging chip, the distance between the target and the camera, the focal length of the camera lens, the angle of incidence of the laser, and the width of the produced image (expressed in pixels). These five variables were evaluated along with error-inducing variables to make recommendations concerning the construction, deployment, use, sensitivity, error and potential of the monitor.
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