Shield-Data-Based Horizon Control for Longwall Shearer Guidance

Coal is an important fuel for energy generation, and since there are no adequate alternatives it will also be for the next decades. The deep lying hard coal is important in particular because of its high energy content. Automation of underground mining has led to major improvements in productivity and safety. A fully mechanized longwall shearer workface has already reached a high degree of automation and provides a high productivity for example utilizing the memory cut. Current researches and developments in longwall mining are focused on extending this method by adaptive cutting drum height adjustment. The so-called horizon control is often based on memory cut methods. Horizon control in this way requires information of the environment, which can be provided by models (seam model, cut model) and coal interface detection (CID). Available CID systems only provide an optimal output under specific conditions. The authors propose the shield-data-based horizon control (SDHC) system as an alternative approach. SDHC does not require information from a CID system or an environmental model. All necessary information is provided by roof supports, shearer and process monitoring. The SDHC system was tested in simulation under different seam conditions and yielded promising results which will be presented in this paper. In cooperation with the German mining company RAG the SDHC has already reached an experimental stage. A test assembly was built up at the surface and the SDHC system was implemented on real mining equipment. To make the test scenario as realistic as possible, the SDHC system was only connected to the monitoring system, not to the simulation model. The aim of these tests was to establish the cooperation between all subsystems, find appropriate controller parameters, locate and address safety critical aspects and finally to achieve an automatic cutting drum height adjustment. An introduction of SDHC for shearer guidance is given in this paper. The experimental tests are described and the control results of the realized SDHC system on the test assembly are shown.