A new approach to real time traffic sign recognition based on colour information

The automatic interpretation of conventional traffic signs is very complex and time consuming. The paper concerns an automatic warning system for driving assistance. It does not interpret the standard traffic signs on the roadside; the proposal is to incorporate into the existing signs another type of traffic sign whose information will be more easily interpreted by a processor. The type of information to be added is profuse and therefore the most important object is the robustness of the system. The basic proposal of this new philosophy is that the co-pilot system for automatic warning and driving assistance can interpret with greater ease the information contained in the new sign, whilst the human driver only has to interpret the "classic" sign. One of the codings that has been tested with good results and which seems to us easy to implement is that which has a rectangular shape and 4 vertical bars of different colours. The size of these signs is equivalent to the size of the conventional signs (approximately 0.4 m2). The colour information from the sign can be easily interpreted by the proposed processor and the interpretation is much easier and quicker than the information shown by the pictographs of the classic signs

PRIM an Open Mobile Robot Platform. Motivation, Present and Future Trends

This paper is focused on the robot mobile platform PRIM (platform robot information multimedia). This robot has been made in order to cover two main needs of our group, on one hand the need for a full open mobile robotic platform that is very useful in fulfilling the teaching and research activity of our school community, and on the other hand with the idea of introducing an ethical product which would be useful as mobile multimedia information point as a service tool. This paper introduces exactly how the system is made up and explains just what the philosophy is behind this work. The navigation strategies and sensor fusion, where machine vision system is the most important one, are oriented towards goal achievement and are the key to the behaviour of the robot

WMR navigation using local potential field corridors and narrow local occupancy grid perception

Path planning and control strategies applied to autonomous mobile robots should fulfil safety rules as well as achieve final goals. Trajectory planning applications should be fast and flexible to allow real time implementations as well as environment interactions. The methodology presented uses the on robot information as the meaningful data necessary to plan a narrow passage by using a corridor based on attraction potential fields that approaches the mobile robot to the final desired configuration. It employs local and dense occupancy grid perception to avoid collisions. The key goals of this research project are computational simplicity as well as the possibility of integrating this method with other methods reported by the research community. Another important aspect of this work consist in testing the proposed method by using a mobile robot with a perception system composed of a monocular camera and odometers placed on the two wheels of the differential driven motion system. Hence, visual data are used as a local horizon of perception in which trajectories without collisions are computed by satisfying final goal approaches and safety criteria

Knowledge integration within an applied mobile robot summer course

This paper presents the use of a mobile robot platform as an innovative educational tool in order to promote and integrate different curriculum knowledge. Hence, it is presented the acquired experience within a summer course named ldquoapplied mobile roboticsrdquo. The main aim of the course is to integrate different subjects as electronics, programming, architecture, perception systems, communications, control and trajectory planning by using the educational open mobile robot platform PRIM. The summer course is addressed to a wide range of student profiles. However, it is of special interests to the students of electrical and computer engineering around their final academic year. The summer course consists of the theoretical and laboratory sessions, related to the following topics: design & programming of electronic devices, modelling and control systems, trajectory planning and control, and computer vision systems. Therefore, the clues for achieving a renewed path of progress in robotics are the integration of several knowledgeable fields, such as computing, communications, and control sciences, in order to perform a higher level reasoning and use decision tools with strong theoretical base

Local WMR navigation with monocular data

This article presents recent WMR (wheeled mobile robot) navigation experiences using local perception knowledge provided by monocular and odometer systems. A local narrow perception horizon is used to plan safety trajectories towards the objective. Therefore, monocular data are proposed as a way to obtain real time local information by building two dimensional occupancy grids through a time integration of the frames. The path planning is accomplished by using attraction potential fields, while the trajectory tracking is performed by using model predictive control techniques. The results are faced to indoor situations by using the lab available platform consisting in a differential driven mobile robot

A survey addressing the fundamental matrix estimation problem

Epipolar geometry is a key point in computer vision and the fundamental matrix estimation is the only way to compute it. This article surveys several methods of fundamental matrix estimation which have been classified into linear methods, iterative methods and robust methods. All of these methods have been programmed and their accuracy analysed using real images. A summary, accompanied with experimental results, is given

Enhanced Model Selection for motion segmentation

In this paper a novel rank estimation technique for trajectories motion segmentation within the Local Subspace Affinity (LSA) framework is presented. This technique, called Enhanced Model Selection (EMS), is based on the relationship between the estimated rank of the trajectory matrix and the affinity matrix built by LSA. The results on synthetic and real data show that without any a priori knowledge, EMS automatically provides an accurate and robust rank estimation, improving the accuracy of the final motion segmentation

Rank estimation of trajectory matrix in motion segmentation

A novel technique for estimating the rank of the trajectory matrix in the local subspace affinity (LSA) motion segmentation framework is presented. This new rank estimation is based on the relationship between the estimated rank of the trajectory matrix and the affinity matrix built with LSA. The result is an enhanced model selection technique for trajectory matrix rank estimation by which it is possible to automate LSA, without requiring any a priori knowledge, and to improve the final segmentation

La Imatge dels pagesos: rústecs, devots, rendistes: S. XIV-XVIII

Exposició de com foren vistos els pagesos per aquells que no ho eren durant l’època medieval i moderna, tot recollint els prejudicis i malentesos relacionats amb aquest punt de vista

Els Naturals i el rei natural en la Catalunya de la Guerra dels Segadors: a propòsit d´un sermó de Gaspar Sala (1641)

La guerra dels Segadors (1640-1652/59) va ser també una guerra d'idees o arguments polítics. A diferència, però, d'altres conflictes anteriors (com ara l'anomenada guerra civil catalana de mitjan segle xv), aquests arguments antagònics conegueren (al Principat i fins i tot mes enllà) una difusió sense precedents; sobretot pel fet que s'expressaren tot sovint per la via impresa

Reglà, l´historiador que volia comprendre el món

Breu ressenya de la vida i obra de l’historiador empordanès Joan Reglà

Noves llums sobre la Guerra de Successió [Ressenya del llibre Els catalans i Felip V: De la conspiració a la revolta, 1700-1705, de Joaquim Albareda i Salvadó]

Historiografia de la guerra catalana de Successió. El llibre que ressenya va obtenir el IV Premi Internacional Jaume Vicens Vives de Ciències Socials

La Marina de la Selva abans dels indianos [Ressenya del llibre Homes, vaixells i mercaderies de Tossa al Grau de València, 1459-1703, de Mario Zucchitello].

Ressenya del llibre 'Homes, vaixells i mercaderies de Tossa al Grau de València, 1459-1703', de Mario Zucchitello. Treball que estudia els intercanvis comercials entre el litoral selvatà i el Regne de València i la seva capital al segle XV

Una Lliçó de numismàtica [Ressenya del llibre Història de la moneda de la Guerra dels Segadors (Primera República Catalana), 1640-1652, de Miquel Crusafont i Sabater]

Ressenya del llibre Història de la moneda de la Guerra dels Segadors (Primera República Catalana), 1640-1652. La Catalunya de la guerra dels Segadors mai no va esdevenir una república, però sí que va actuar com si ho fos en matèria monetària. L’obra tracta el paper, no sols de caire econòmic, que va jugar la moneda en aquell temps

Malgrat tot, són aquí

Comentari sobre l’excés de premis literaris catalans i valoració de la influència del premi Casero