Figure 2From: Mobile sailing robot for automatic estimation of fish density and monitoring water qualityThe robot trajectory. (a) The area covered by the sonar Ts with cone angle α and height k (1– robot, 2– sonar beam, 3– trajectory); (b) The way of marking the width of the sonar beam at the bottom (Tm- the distance between adjacent tracks, p s – a sample distribution of fish of the same surface).Back to article page