Abstract: A method and apparatus for horizon control in a mining operation where fresh product 3 is cut from a seam 1. The cutting exposes a fresh cut product face 25. The fresh cut product face 25 is observed at a position immediately adjacent a cutter 11. Any temperature contrast regions from an IR observation between an upper limit of observation and a lower limit of observation are noted. At least one height co-ordinate position of a temperature contrast region 33 is determined and an output signal provided of the determined height co-ordinate position so that the output signal can be used as a horizon datum for horizontal control.

Abstract: A method and apparatus for horizon control in a mining operation is provided. Fresh product 3 is cut from a seam 1. The cutting exposes a fresh cut product face 25. The fresh cut product face 25 is observed at a position immediately adjacent a cutter 11. Any temperature contrast regions from an IR observation between an upper limit of observation and a lower limit of observation are noted. At least one height co-ordinate position of a temperature contrast region 33 is determined and an output signal provided of the determined height co-ordinate position so that the output signal can be used as a horizon datum for horizontal control.

Abstract: A control system for a mining machine which moves in passes across a seam to be mined using absolute coordinates is disclosed. The machine is carried on rail and co-ordinates of the rail are measured along the length of rail. The rail is then moved to a new position for a next pass, and the distance of moving is determined from the co-ordinates previously measured. By knowing the co-ordinates, the rail can be moved to assume a desired profile, so that a desired profile of the seam can be achieved on the next pass. Co-ordinates of the up and down movement of a shearing head can also be measured and stored with the co-ordinates along the rail to provide a profile of the seam being cut, and so that on a next pass the intended position of the shearing head can be predicted and moved accordingly.

Abstract: A mining machine (7) is provided which moves from side-to-side in sequential passes across a seam of material to be mined. The machine (7) is carried on rail means (19) and co-ordinate positions of the rail means (19) are measured at locations along the length of the rail means. A trailing part of the rail means (19) is then moved by rail moving means (25) to a new position for a next pass, and the distance of moving is determined from the co-ordinates of the positions previously measured. By knowing the co-ordinates of the positions, the rail means (19) can be moved to assume a desired profile, so that a desired profile of the face of the seam can be achieved on the next pass of the machine (7). Desirably the profile is a straight line.