Toda Corporation and construction consultant Kinsoku (Minami Ward, Kyoto City, President Katsuji Okuno) have jointly developed automatic surveying technology that can improve the efficiency of surveying management for shield tunnel construction. Using a stereo camera that simultaneously captures the target object with two cameras and also records information in the depth direction (distance), the captured images inside the shield machine are analyzed. The position and posture of the shield machine can be grasped continuously even during excavation.
In-flight measurement image (from press release materials)
When performing automatic surveying in shield construction, an automatic tracking type surveying device (total station) is installed in the tunnel, and surveying is performed by looking at the reference point in the rear and at least two targets inside the shield machine. When excavation progresses and the distance is too far, or when construction is on a curved section, the surveying equipment cannot be sighted at the target, and it takes time to replace the surveying equipment.
The developed automatic surveying technology "MWMS (Mum System)" uses a stereo camera to automatically photograph the end of the shield jack and multiple markers installed on the main body of the shield machine. Analyze the image and survey the shield machine's position (plane/vertical coordinates) and attitude (horizontal direction, tilt).
By fixing the stereo camera to the trailing equipment at the rear of the shield machine, it is possible to save the trouble of replacing the surveying equipment, and it can be applied to tunnels with relatively small cross-sections where it was difficult to arrange the surveying equipment itself due to contact with the traveling cart. I made it
During excavation and segment assembly work, the reference points are exchanged according to the movement of the shield jack, which repeats expansion and contraction like an inchworm, and the front and rear markers are continuously captured. The frequency of surveying can be freely set, and continuous surveying is possible, which improves construction accuracy. We conducted a demonstration experiment of the system at the company's shield construction site and confirmed its practicality.
