A photogrammetric method for monitoring sandbank movement

摘要

An automatic stereopair exposure system (ASES), which employs non-metric digital camera and control bars, was developed aiming at monitoring sandbank movement in a way of non-contact, succession, low cost with satisfied accuracy. Control bars was placed in front of camera, replacing the conventional ground control points (GCPs); non-metric digital camera, computer-controlled exposure without using total station at monitoring time, and automatically locating feature point serve a solution to non-contact monitoring. A theoretical experimentation for accuracy test showed that relative accuracy from 1/1500 to 1/20000 could be available, with the variation of space resection to calculate the exterior orientation parameters. In the practical application of Enshu-nada coast, estuary of Kiku River of Shizioka Prefecture, Japan, the method of fixing camera position provided height direction with an accuracies of 1/1442 and 1/7211, to the longest photographic distance and the shortest photographic distance, respectively, compared with total station (TS). The method is flexible and is accurate enough for monitoring sandbank movement.