Category: Uncategorized

CeRVIM Seminar

Convolutional neural networks and visual illusions: Can they fool each other?

Javier Vazquez-Corral
Associate Professor, Autonomous University of Barcelona
Researcher, Computer Vision Center, Barcelona

Tuesday, July 4, 2023, 2:30 p.m., PLT-3370

Abstract
Visual illusions teach us that what we see is not always what is represented in the physical world. Their special nature makes them a fascinating tool to test and validate any new vision model proposed. In general, current vision models are based on the concatenation of linear and non-linear operations. The similarity of this structure with the operations present in Convolutional Neural Networks (CNNs) has motivated us to study two research questions:
– Are CNNs trained for low-level visual tasks deceived by visual illusions? If this is the case, a way to obtain CNNs that better replicate human behaviour, might be to start aiming for them to better replicate visual illusions.
– Can we use current deep learning architectures to generate new visual illusions that trick humans?

References
[1] “Convolutional neural networks can be deceived by visual illusions” A Gomez-Villa, A Martin, J Vazquez-Corral, M Bertalmío, CVPR 2019
[2] “Color illusions also deceive CNNs for low-level vision tasks: Analysis and implications”, A Gomez-Villa, A Martín, J Vazquez-Corral, M Bertalmío, J Malo, Vision Research 176, 156-174
[3] “On the synthesis of visual illusions using deep generative models”, A Gomez-Villa, A Martín, J Vazquez-Corral, M Bertalmío, J Malo, Journal of Vision 22 (8), 2022

Biography
Javier Vazquez-Corral is an Associate Professor at the Autonomous University of Barcelona and a researcher at the Computer Vision Center. Prior to that, he held post-doctoral positions both at the Universitat Pompeu Fabra in Barcelona and at the University of East Anglia in Norwich, United Kingdom. His main research interest is computational colour, in which he has developed novel approaches to solve different problems ranging from colour constancy to colour stabilization, colour characterization, colour gamut mapping, high dynamic range imaging, image dehazing, image denoising, and vision colour properties such as unique hue prediction and colour naming.

The presentation will be given in English and the slides will be in English.

CeRVIM Seminar: Simultaneous fluorophore discrimination and resolution improvement of super-resolution images using fluorescence lifetime

Andréanne Deschênes
CERVO Research Centre, Université Laval

Friday, April 28, 2023, 11 a.m., PLT-3370

Abstract
To study the interactions between neuronal proteins with fluorescence microscopy, simultaneous observation of multiple biological markers is required. SPLIT-STED, an approach exploiting the analysis of fluorescence lifetime was developed to improve the spatial resolution of STimulated Emission Depletion microscopy. We developed an analysis using linear combination of components in phasor space to multiplex SPLIT-STED and apply it to separate two spectrally indistinguishable fluorophores per imaging channel. We quantify and characterize the performance of our algorithm on simulated images constructed from real single-staining images.This allows us to perform simultaneous resolution improvement and colocalization analysis of multiple protein species in live and fixed neuronal cultures.

The presentation will be given in English and the slides will be in English.

CeRVIM Seminar : Kilometer-scale autonomous navigation in subarctic forests: challenges and lessons learned

Dominic Baril
Norlab (Northern Robotics Laboratory)
Dép. d’informatique et de génie logiciel, U. Laval

Friday, March 3, 2023, 1:30 p.m., PLT-2501 and on Zoom

Abstract

With recent major advances in mobile robotics, it is now possible to deploy robots in various scenarios to support a variety of industries. However, few studies document the impact of winter conditions and the boreal forest on autonomous navigation systems. This is why we present a field report on the deployment of an autonomous navigation system in the Montmorency Forest, in the province of Quebec, in Canada. As part of this work, we have designed an autonomous navigation system based on the registration of point clouds measured by lidars to locate the vehicle and map the environment. We have demonstrated the ability of the system to navigate 18.8 km independently on forest trails in harsh winter conditions. We present the impact of vegetation and snow accumulation on autonomous navigation algorithms. The presentation will conclude with a discussion concerning the challenges to be met in order to achieve robust autonomous navigation under the conditions encountered in this deployment.

This presentation is based on the article (https://arxiv.org/abs/2111.13981) which has been published in the journal Field Robotics.

Biography
Dominic Baril is a Ph.D. student in Computer Science under the supervision of Professors François Pomerleau and Philippe Giguère. As part of his research in the Norlab, Université Laval’s mobile robotics laboratory, he seeks to increase the robustness of path-following algorithms for autonomous vehicles under variable traction conditions, more specifically snow-covered terrain. He has coordinated numerous field trials with a 500 kg robot in the Montmorency Forest during which the impact of the environment was quantified on a state-of-the-art autonomous navigation system.

The presentation will be given in French and the slides will be in French.

To obtain the Zoom meeting web link, please contact:
Annette.Schwerdtfeger@gel.ulaval.ca

CeRVIM Seminar: 3D metrology and astronomical instrumentation: an exoplanet searcher in Chile

Anne-Sophie Poulin-Girard
Laboratoire de Recherche en Ingénierie Optique, LRIO
Dép. de physique, de génie physique et d’optique, U. Laval

Friday, February 3, 2023, 11:00 a.m., PLT-3370

Abstract
The use of metrology devices such as portable measuring arms, CMM and 3D scanners is increasingly widespread in the field of astronomical instrumentation. These tools are used to align the optical and mechanical parts of these instruments, thus making it possible to respect very strict positioning tolerances, often below 100 microns for a complex optomechanical assembly.

In this context, the presentation will focus on the exoplanet detection astronomical instrument NIRPS (Near Infra-Red Planet Searcher), more precisely on the assembly, integration, test and validation (AITV) phase of the spectrograph of the instrument. I will also discuss the AITV mission at the European Southern Observatory – La Silla in the Chilean desert in 2022. This presentation is a great opportunity for those who are interested in astronomy, who want to learn more about the field of astronomical instrumentation and potential future collaborations, or who simply wish to see the magnificent landscapes of Chile.

Biography
Anne-Sophie Poulin-Girard received her Ph.D. from Université Laval in 2016, under the supervision of Profs. Simon Thibault and Denis Laurendeau. Her thesis focused on the use of panoramic lenses in 3D reconstruction, at the boundary between optical engineering and computer vision. Following her Ph.D., she became the scientific coordinator of the Canada Excellence Research Chair in Neurophotonics. In 2017, she returned to Prof. Thibault’s team as a research associate. She is also scientific and technical coordinator of the NSERC Industrial chair in optical design. She currently participates in several research and development projects in collaboration with industry, and is involved in the assembly, integration and testing phase for the spectrograph of NIRPS, an instrument dedicated to the detection of exoplanets. Passionate about education, she was the chair of the SPIE Education committee and has hosted the international conference SPIE/OSA/IEEE/ICO Education and Training in optics and photonics in 2019 and is the co-chair of Optics Education and Outreach conference at SPIE O+P since 2020. Since 2021, she is also a member of the Natural Sciences and Engineering Research Council of Canada (NSERC).

The presentation will be given in French and the slides will be in English.

CeRVIM Webinar: Introduction à la segmentation sémantique (par Intelligence Artificielle) sur MATLAB

William Bonilla
1. Laboratoire LVSN
Dép. de génie électrique et de génie informatique, U. Laval
2. Test Engineer Intern, Tesla

Friday, December 2, 2022, 11:00 a.m.

Résumé
L’intelligence artificielle est un outil de plus en plus accessible qui est très prisé aujourd’hui. Les chercheurs ont donc plus de choix lorsque vient de le temps de choisir une plateforme pour développer leurs algorithmes d’intelligence artificielle.  Récemment, MATLAB a réussi à produire une solution facile d’utilisation qui permet de développer des algorithmes d’intelligence artificielle. La présentation portera sur toutes les étapes pour la réalisation d’un algorithme d’intelligence artificielle capable d’effectuer la segmentation sémantique sur MATLAB.
Le code sera partagé suite à la présentation.

The presentation will be given in French and the slides will be in French.

To obtain the Zoom meeting web link, please contact:
Annette.Schwerdtfeger@gel.ulaval.ca

CeRVIM Seminar: A Hybrid Approach for the Motion Control of Kinematically Redundant Hybrid Parallel Robots

Sy Nguyen
Laboratoire de robotique
Dép. de génie mécanique, Université Laval

Friday, November 18, 2022, 12:00 p.m.
Room PLT-3370

Abstract
Classical methods for the motion control of robots are based on the dynamic model of the robot. The dynamics and the errors can then be examined either in the joint coordinates or in the task coordinates. Each of these two approaches has advantages and drawbacks, and this results in two versions of several control techniques such as PD+Gravity Compensation or Computed-Torque. The hybrid method that combines both approaches to control Kinematically Redundant Hybrid Parallel Robots is introduced in this presentation. In short, the two approaches are applied to different parts of the robot and the control signal is then determined based on their combination. In addition to improving the position control performance, this method reduces the modeling process. The robot is divided into two main components and each component is modeled separately. Furthermore, the position and orientation of the robot are considered in the Cartesian space, which is more obvious and easier to work with. Several demo videos are shown to demonstrate the performance of this control method. Extended works for force-related control are discussed.

The presentation will be given in English and the slides will be in English.

IID Seminar: Apprentissage ouvert en robotique
(Open-Ended Learning in Robotics)

Stéphane Doncieux, directeur adjoint
ISIR (Institut des systèmes intelligents et de la robotique)
Sorbonne Université, CNRS, Paris

Wednesday, September 14, 2022, 2:30-3:30 p.m.
Room COP-1168 (Centre d’optique-photonique-laser, Pavillon Vachon)

Abstract

Les robots actuels peuvent accomplir des tâches complexes avec une grande précision, mais pour cela, ils doivent rester dans un environnement contrôlé. Faire face à la variabilité d’un environnement non contrôlé reste un défi. L’apprentissage machine devrait pouvoir donner aux robots les capacités d’adaptation requises, mais la robotique dispose de caractéristiques qui en font un domaine d’application particulièrement exigeant pour les méthodes d’apprentissage. Rendre les robots adaptatifs nécessite de plus de s’intéresser à des apprentissages “ouverts”. Nous positionnerons cette notion par rapport au cadre de l’apprentissage par renforcement et nous présenterons les résultats obtenus dans l’équipe sur les questions que posent un tel apprentissage, que ce soit pour acquérir des représentations d’espaces d’état ou pour explorer dans le cas de récompenses rares. Les applications iront, selon les cas, de problèmes jouets en simulation à la saisie d’objets sur robots réels.

Biography

Stéphane Doncieux is a Computer Science Professor at ISIR (Institute of Intelligent Systems and Robotics), Sorbonne University, CNRS, Paris.
Since January 2019, he has been Deputy Director of ISIR, a multidisciplinary robotics laboratory that brings together researchers in mechatronics, computer science, signal processing and neuroscience. He was coordinator of the DREAM FET H2020 project from 2015 to 2018 (https://dream.isir.upmc.fr/). His research focuses on cognitive robotics and in particular on learning and adaptation with an evolutionary and developmental approach.

The presentation will be given in French and the slides will be in English.

For more information, please contact:
Annette.Schwerdtfeger@gel.ulaval.ca

CeRVIM Webinar: Going beyond 3D to estimate the scene geometry and semantics

Raoul de Charette
Scientifique de recherche, INRIA Paris

Hybrid CeRVIM Webinar (co-modal)
June 14, 2022, 2:00 p.m.
Room (in person) : PLT-1120
Zoom (virtual) : https://ulaval.zoom.us/j/64359268203?pwd=U0lzaGFvNWJTNW1zWDFzbitMbzZCZz09

Abstract
Estimating scene geometry and semantics is a prerequisite for visual systems to interact with our physical 3D world. Because they are largely intertwined, these two cues are better estimated jointly.
In this line of research, I will present some of our recent works that estimate the complete 3D information either leveraging 3D data with lightweight 2D backbones, or using monocular 2D images. Beyond the visible scene parts, we will see that additional insights can boost estimation of the occluded areas.

The presentation will be given in English and the slides will be in English.

REPARTI Workshop 2022: Friday, May 13, 2022, 8h45 – 15h15, on Zoom* within the Acfas Conference.

Three keynote presentations, each followed by a series of short presentations, all of which are offered by researchers and students from the member institutions of REPARTI, will allow you to learn more about the research projects and initiatives carried out by REPARTI members. Here is the detailed program which includes the titles of all of the presentations:

REPARTI Workshop 2022 Program

*To obtain the Zoom meeting web link, please access the Acfas website, https://www.acfas.ca/ and connect to your user account linked to your registration for the Acfas conference. Then go to the Colloque #205 webpage and click on “Accéder à la plateforme”.

CeRVIM Webinar: Initiation à la classification de nuages de points

Geneviève Le Houx
Laboratoire LVSN
Dép. de génie électrique et de génie informatique, Université Laval

May 6, 2022, 11:00 a.m.

Abstract
Ce projet, réalisé dans le cadre du cours GEL-7065 – Lectures dirigées en génie électrique III, porte sur la classification de nuage de points. Les nuages de points proviennent de la base de données “RGB-D Object Dataset” disponible sur le web. Ces données contiennent de l’information sur la position ainsi que sur la couleur de chaque point. Le webinaire présentera les différentes étapes pour effectuer la classification des nuages de points: le prétraitement des données, l’extraction de descripteurs ainsi que l’application de l’apprentissage automatique à des fins de classification.

The presentation will be given in French and the slides will be in French.

To obtain the Zoom meeting web link, please contact:
Annette.Schwerdtfeger@gel.ulaval.ca