| 摘要 |
PURPOSE:To correctly carry out excavation along an excavation planned road line. CONSTITUTION:A transmitter 1 is previously installed along the excavation planned road line of a shield machine. A receiving machine 3 installed on the shield machine 2 receives the electric waves transmitted from the transmitter installed in front, and determines the excavation planned road line before the shield machine, and excavation is carried out along the determined excavation planned road line. |
