Computer vision and robotics techniques in fish farms

This paper presents new low-cost systems for the automation of some fish farm operations. Particularly, computer vision is applied to noncontact fish weight estimation. Stereo vision systems with synchronised convergent cameras are employed to perform fish 3-D segmentation in tanks and sea cages. Several pre-processing algorithms are applied to compensate illumination local variations. The approach applied for fish 3D segmentation consists in detecting in both images certain fish features. Once these points have been detected and validated in both images, the fish are 3-D segmented by applying stereo vision matching considerations. Fish weight is estimated by using simple length-weight relations well known in the aquaculture domain. The paper also presents a robotic system for fish feeding and an underwater robot for autonomous pond cleaning.