La caminería en al-Andalus (ss. VIII-XV J.C.): consideraciones metodológicas, históricas y administrativas para su estudio

Este estudio es una síntesis de las últimas aportaciones acerca de las vías en al-Andalus (ss. VIII-XV), cuya estructura inicial es herencia de la época romana. Dadas las limitaciones que imponen los escasos datos que hallamos en las fuentes árabes y los pocos restos camineros conocidos, se hace necesario emplear una nueva metodología de investigación: Se aborda el objeto como un estudio global, no sólo de los caminos, sino de todos los elementos interrelacionados con ellos, denominados como "espacios viales". Luego se presenta la indisoluble relación de los "espacios viales" con los castillos y torres ("espacios de control y defensa") en al-Andalus, como los vigilantes de los caminos, y se enuncia la toponimia árabe relacionada tanto con los "espacios viales" como con los "espacios de control y defensa". Finalmente, se recogen los datos que las diversas crónicas árabes nos proporcionan acerca de la política viaria en al-Andalus a lo largo del tiempo, así como sobre quién era el responsable de velar por el buen estado de los tramos viales.

Event-based visual servoing

Traditional visual servoing systems have been widely studied in the last years. These systems control the position of the camera attached to the robot end-effector guiding it from any position to the desired one. These controllers can be improved by using the event-based control paradigm. The system proposed in this paper is based on the idea of activating the visual controller only when something significant has occurred in the system (e.g. when any visual feature can be loosen because it is going outside the frame). Different event triggers have been defined in the image space in order to activate or deactivate the visual controller. The tests implemented to validate the proposal have proved that this new scheme avoids visual features to go out of the image whereas the system complexity is reduced considerably. Events can be used in the future to change different parameters of the visual servoing systems.

Control framework for dexterous manipulation using dynamic visual servoing and tactile sensors’ feedback

Tactile sensors play an important role in robotics manipulation to perform dexterous and complex tasks. This paper presents a novel control framework to perform dexterous manipulation with multi-fingered robotic hands using feedback data from tactile and visual sensors. This control framework permits the definition of new visual controllers which allow the path tracking of the object motion taking into account both the dynamics model of the robot hand and the grasping force of the fingertips under a hybrid control scheme. In addition, the proposed general method employs optimal control to obtain the desired behaviour in the joint space of the fingers based on an indicated cost function which determines how the control effort is distributed over the joints of the robotic hand. Finally, authors show experimental verifications on a real robotic manipulation system for some of the controllers derived from the control framework.

Direct Visual Servoing Framework based on Optimal Control for Redundant Joint Structures

This paper presents a new framework based on optimal control to define new dynamic visual controllers to carry out the guidance of any serial link structure. The proposed general method employs optimal control to obtain the desired behaviour in the joint space based on an indicated cost function which determines how the control effort is distributed over the joints. The proposed approach allows the development of new direct visual controllers for any mechanical joint system with redundancy. Finally, authors show experimental results and verifications on a real robotic system for some derived controllers obtained from the control framework.