The winning tool carried for universal movement by the frame of a tunneling machine is controlled by a system and method to limit tool movement in a manner to form a tunnel with a desired cross section. Positioning of the winning tool is determined in relation to a laser beam projecting along the length of the tunnel while the range of universal movement by the winning tool is limited by a set of tool coordinate values determined by scanning a pattern, template or the like defining an outline that is geometrically similar to the desired cross section of the tunnel. The tunneling machine carries a receiver for the laser beam that irradiates front and rear detectors each including an array of photodetectors. Servomotors respond to an output signal from the front detector to align the receiver by a translating motion so that the laser beam passes through a single passageway in the front detector to irradiate the rear detector. The servomotors drive position transducers that provide output signals corresponding to the translating motion. These output signals are used to modify signals representing the set of tool coordinate values which are also modified by an output signal from the rear detector that corresponds to angular travel by the mining machine relative to the laser beam. An inclinometer or other means provides a signal used to prevent horizontal deviations transversely of the tunnel roadway during the tunneling operation.
展开▼
