Measurement of surface velocity in open channels\ud using a lightweight remotely piloted aircraft\ud system

摘要

In this paper, a low-cost remotely piloted aircraft system (RPAS) technique\udis proposed for measurement of the surface velocity in rivers or channels\udwith low surface velocity and small discharge. To verify the reliability of\udthe results obtained with the RPAS, we simultaneously measured the\udsurface velocity with other methods based on total stations and close\udrange photogrammetry. The RPAS was used both with ground control\udpoints (GCPs) for orientation of the photographic images and without\udGCPs. The data analysis showed that the RPAS provides valid results even\udwithout GCPs. Use of a RPAS without GCPs, relying solely on flight altitude\udto determine the water velocity, opens the way for its utilization in\udemergency conditions when it is impossible to access the river banks for\udthe realization and survey of GCPs