Research Activity of Underwater Vehicles in Korea and an Underwater Stereo Camera for 3-D Images

摘要

Korea has been exerting her efforts to exploit and preserve the ocean. To meet the needs of ocean exploitation, several vehicles have been developed in Korea since 80's. Recently, we establish a plan to develop an unmanned underwater vehicle to probe the deep sea for the purpose of scientific research. This paper introduces the present and future research activity of underwater vehicles in Korea. This paper also describes the vergence control of a parallel stereo camera and its application to underwater stereo camera to enhance the working efficiency of underwater vehicles equipped with manipulators in seabed operation. The stereo camera consists of two parallel lenses mounted on a lateral moving base and two CCD cameras mounted on a longitudinal moving base, which is embedded in a small pressure canister for underwater application. Because the lateral shift is related to the backward shift, only one control input is needed to control the vergence and focus of the camera. We can get a clear stereo vision with the camera for all the range of objects in air and in water, especially in short range objects. The control system of the camera is so simple that we are able to realize a small stereo camera system and to apply it to a stereo vision system for underwater vehicles. This paper also shows how to acquire the distance information of an underwater object with this stereo camera. Whenever we focus on an underwater object with the camera, we can obtain the three-dimensional images and the distance in real-time.