Radar Level Sensor for Longwall Creep and Retreat Measurement

The use of a commercial radar level sensor for measuring two critical parameters related to the longwall coal mining process is investigated. An overview of the longwall coal mining process is provided, and the parameters known as longwall creep and longwall retreat are explained. The test environment and methodology used to simulate these parameters is described, along with the commercial radar level sensor that was employed. The test results are presented, including a comparison of the retreat testing using a flat plate target with a theoretical model based on the geometrical theory of diffraction. It was found that the radar sensor functions effectively as a tool for longwall creep measurement, and that it also shows great potential for measuring longwall retreat.