Pioneering techniques pave the way for future underwater surveying
27 March 2015
Scientists are studying the use of computer vision and robotics technologies to survey the seabed of Cardigan Bay, in place of more costly and time-consuming techniques.
Scientists at the Department of Computer Science at Aberystwyth University have been working with marine conservation group, Friends of Cardigan Bay, to develop better techniques for studying the seabed, which is vital for marine conservation and fisheries management. Until recently the work of mapping and recording the seabed had been conducted using the traditional 'researcher and clipboard' technique, which is costly and time consuming.
The project has been looking at how video images of the sea floor can be reviewed by utilising computer software programs that assist conservationists in the classification of different habitats.
The work was undertaken by postgraduate student Matt Pugh, marine expert Phil Hughes from Friends of Cardigan Bay, and Dr Bernie Tiddeman and Dr Hannah Dee from the University's Department of Computer Science. According to Phil Hughes, the initial idea was that computer vision and machine learning techniques could provide new perspectives on the analysis of undersea video.
"The key question we wanted to address was that of 'substrate classification'," says Dr Hannah Dee. "Put simply, can we wave a video camera around underwater, and map the seafloor from the video we get back? Natural Resources Wales have a classification system which categorises the seafloor into a number of different classes, from fine sands to rocky areas.
We wanted to create a simplified version of this using modern technology, and ensure that visually similar areas fell into the same categories. Once we had completed this phase, the next challenge was to analyse underwater video collected by Friends of Cardigan Bay and Bangor University to try to build a classification automatically. The project obtained good classifications and was a major achievement considering it was a one year project."
The team are now looking at novel ways of acquiring undersea video. A kit robot - Open ROV - has been built and tested in a nearby lake. Operated from a laptop, usually from a boat on the surface, the robot can navigate its way around the seafloor, and uses lights and cameras to record the submarine world. The team hope that the robot will be ready in the summer for data collection.
"For this coming year we will be concentrating on obtaining much better quality sea bed video for future projects involving computer vision," says Phil Hughes. "It is hoped that this, combined with the robotics side, could be developed further, which would change significantly how current data is obtained. This currently involves the use of a survey vessel, creates a huge carbon footprint, and hours of a person's time to sit down and evaluate the videos produced."