<html data-lt-installed="true"> <head> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body style="padding-bottom: 1px;"> Olá a todos, Durante a próxima semana haverá duas palestras relativas a tópicos de Visão por Computador. Em ambas as palestras se discutem as aplicações da estimação de rectas 3D a partir de dados como câmaras, LIDARs e sensores equivalentes. A 1ª palestra terá lugar no Anfiteatro do ISR, às 11 horas do dia 23 de Maio e terá como tópico "Análise de Rectas em Superfícies com Simetria Rotacional. Título e bio: ________________________________________________ Calculus of lines on surfaces with rotational symmetry In this talk we focus on 3D-surfaces that are swept by a moving line that rotates around a fixed axis. These surfaces appear in CAD and engineering applications with Galvano laser scanners, Lidars, rotating camera's, moving robot joint axes, etc... We explain how we can represent a ruled surface of revolution by 3 lines, such that each of its lines is obtained as a linear combination of this triple. Furthermore, the coefficients of these linear combinations can be directly expressed in function of the rotation angles. As an application we briefly show how these linear combinations provide an alternative calibration model for certain 3D-sensors, avoiding the determination of intrinsic parameters. Bio: Rudi Penne has been trained as a mathematician at the University of Antwerp (Belgium), where he received his doctorate in 1992, in the twilight zone between algebra, combinatorial and projective geometry, and mechanical applications. His current position is a logical continuation of his PhD research: professor at the faculty of applied engineering of the University of Antwerp. His main fields of interest: computer vision (geometric modelling and calibration), projective (line) geometry, rigidity theory and combinatorial/computational geometry). A significant portion of his time is dedicated to the popularization and communication of maths to a broad public. ______________________________________________________________________ A segunda "talk" terá lugar também no Anfiteatro do ISR, às 14h 30m do dia 24 de Maio e terá como tópico a relação entre estimação de rectas em 3D e "machine learning". Título e bio: __________________________________________________________ <div dir="auto"> </div> <div dir="auto">On straight lines and how machine learning screws them</div> <div dir="auto"> </div> <div dir="auto"> </div> <div dir="auto">Straight lines appear in a wide variety of industrial applications and measuring techniques, such as robotics, LiDAR, cameras, 3D laser scanners, … . After providing a few examples, we review the basics of line geometry: Plücker coordinates for straight lines, the Klein quadric and a little bit of screw theory. Armed with this knowledge, we revisit the earlier examples. In the second half, we present challenges we face when we apply constrained Gaussian process regression to predict straight lines and not just numbers (the same goes for any machine learning technique in a generative setting). We look at two use cases: the calibration of a galvanometric laser setup and the approximation of point clouds using line elements. This talk covers a large range of theoretical concepts in an intuitive and visual way.</div> <div dir="auto"> </div> <div dir="auto"> </div> <div dir="auto">Bio </div> <div dir="auto"> </div> <div dir="auto">Ivan De Boi received his master’s degree in electronics and ICT from the University of Antwerp, Antwerp, Belgium, in 2001. After working as a Project Engineer for seven years in industry, he became a Lecturer at the Karel de Grote University College, Antwerp. Apart from his teaching assignment, he also worked on various research projects in the field of artificial intelligence and AR/VR, mainly in healthcare and Industry 4.0 context. In 2020, he joined the Research Group InViLab, University of Antwerp, to work on calibration procedures of 3D sensors using line variety models.</div> <div dir="auto"> ______________________________________________________________ Cordiais saudações académicas, Helder Araújo </div> </body> <lt-container></lt-container> </html>