Automatic measurement appts for progress of tunnelling machinery - includes computer for evaluation of images supplied by video camera trained on light boxes in machinery under propulsion

摘要

An exposure device (esp video camera) (1) is rigidly installed behind the excavating machinery (7) in the main tunnel (8) or pilot tunnel, and directed at two light boxes (2, 3) arranged at least 1 m apart along the machinery facing the camera. A computer (5) processes the video image and deduces the position (p) and orientation of the machinery w.r.t the camera position. The orientation angle of the camera is monitored and corrected continuously by a reference light (6) in the field of view. ADVANTAGE - More accurate and positive surveying can be carried out more quickly by less qualified operators.