Synchronizing a modular robot colony for cooperative tasks based on intrainter robot communications

The implementation of robotic cooperative tasks such as pushing an object toward a desired destination or manipulating an object using mobile robots or robotic arms requires motion coordination between the robot colony. When a robot is built by the union of several robots, such as modular robot systems, it is critical to have the complete coordination of each robot configuration within the colony and also overall robot coordination of the colony. The paper presents a demonstration of parallel motion for modular robot configurations through the combination of two types of communications, i.e., Inter-robot and Intra-robot communications. The two types of communications are described and implemented in a real modular robot system. Experiments are executed to show the performance of the robot colony synchronizatio

Revisión del componente achelense de la industria lítica de Galería (Atapuerca, Burgos, España)

The lithic industry of the Galería site at the Atapuerca complex (Burgos), dated to the second half of the Middle Pleistocene, has been interpreted as one of the most remarkable assemblages of the Acheulean technocomplex known in the Iberian Peninsula and southern Europe. It has been considered that the long stratigraphic sequence of the site allows the observation of the evolution of the Acheulean in the second half of the Middle Pleistocene. This proposal has been the subject of a recent review on our part, in which the discontinuous nature of the stratigraphy at Galería is highlighted, and the possibility of establishing any type of archaeological sequence based on the limited record it contains is negatively valued. The attribution of the archaeological sites at Galería exclusively to the Acheulean techno-complex is also discussed, based on a level-by-level analysis of the representativeness of the published lithic industry. In order to assess the Acheulean attribution in-depth, and to contrast the consistency of the evolutionary trends that have been proposed for this techno-complex through the stratigraphy of Galería, we present here a detailed study of all the artifacts interpreted in previous publications as “LCTs” (handaxes, cleavers and other macro-tools). This work, complementary to our previous review, has been carried out on the collections obtained in the field seasons undertaken in Galería between 1982 and 1996, currently deposited at CENIEH and the Museum of Evolution (Burgos). The conclusions reached corroborate the weak and discontinuous presence of characteristic Acheulean elements in this site, ruling out the possibility of recognizing any type of evolutionary sequence in these materials. Our main conclusion is that the interpretations that propose to see in the industry of Galería as a representative sequence of the European Acheulean which evolves progressively, have no base.La industria lítica del yacimiento de Galería (complejo de Atapuerca, Burgos), datado en la segunda mitad del Pleistoceno Medio, ha sido interpretada como uno de los más notables conjuntos del tecnocomplejo achelense que se conocen en la península ibérica y en el sur de Europa. Se ha estimado que su prolongada secuencia estratigráfica permitiría observar la evolución del Achelense en la segunda mitad del Pleistoceno Medio. Esta propuesta ha sido objeto por nuestra parte de una revisión reciente, en la que se destaca el carácter discontinuo de la estratigrafía de Galería y se valora negativamente la posibilidad de establecer cualquier tipo de secuencia arqueológica basada en el limitado registro que contiene. A partir del análisis nivel por nivel de la representatividad de la industria lítica publicada, se discutía además en ese trabajo la atribución exclusiva al tecnocomplejo achelense de los conjuntos arqueológicos de Galería. Con objeto de valorar en profundidad la atribución achelense y de contrastar la consistencia de las tendencias evolutivas que han sido propuestas para este tecnocomplejo a través de la estratigrafía de Galería, presentamos aquí un estudio detallado de todos los artefactos interpretados en publicaciones precedentes como LCT (bifaces, hendedores y otros macro-útiles). Este trabajo, complementario de nuestra revisión anterior, se ha efectuado sobre las colecciones obtenidas en las campañas realizadas en Galería en 1982-1996, actualmente depositadas en el CENIEH y en el Museo de la Evolución Humana (Burgos). Las conclusiones alcanzadas corroboran la débil y discontinua presencia de elementos achelenses característicos en este yacimiento, descartando la posibilidad de llegar a reconocer cualquier tipo de secuencia evolutiva en estos materiales. Nuestra principal conclusión es que las interpretaciones que proponen ver en la industria de Galería una secuencia representativa del Achelense europeo con una evolución progresiva, carecen de fundamento

The estación de las Delicias site (Madrid) and paleolithic research in the Manzanares valley

El yacimiento madrileño de las Delicias, excavado por Obermaier y Wernert en 1918, ha sido durante décadas uno de los más notables del conjunto de localidades paleolíticas clásicas del valle del Manzanares. En el presente artículo se hace un repaso crítico de la documentación ofrecida por la antigua excavación, se evalúan historiográficamentelas distintasinterpretaciones vertidas sobre la industria del yacimiento y se enumeran algunos de los objetivos sobre los que construir un nuevo proyecto de excavación sobrelos depósitos aún conservados del mismo.The archaeological site of Las Delicias (Madrid) excavated by Obermaier andWernert in 1918, it has been one of the most important classic palaeolithic sites of the Manzanares valley for years. In this paper we offer a critical review of all the data caming from ancient excavation, together with an historiographical evaluation of the different interpretations based on lithic industry of the site, and finally we want to set some objectives looking for a new archaeological research in the Delicia´s remaining sediment

An Active helideck testbed for floating structures based on a Stewart-Gough platform

A parallel robot testbed based on Stewart-Gough platform called Active-helideck is designed, developed and tested as a helicopter floating helideck. The objective of this testbed is to show the advantages of helicopters that use an active helideck upon landing on and taking off from ships or from offshore structures. Active-helideck compensates simulated movements of a ship at sea. The main goal of this study is to maintain the robot’s end effector (helideck) in a quasi-static position in accordance to an absolute inertial frame. Compensation is carried out through the coordinate action of its six prismatic actuators in function of an inertial measurement unit. Moreover, the simulation of the sea movement is done by a parallel robot called ship platform with three degrees of freedom. The ship platform is built with a vertical oscillation along the z axis, i.e. heave, and rotates on remaining axes, i.e. roll and pitch. Active helideck is able to compensate simulated movements by considering the ship as an inertial frame as observed in the experiment

Modelling of Modular Robot Configurations Using Graph Theory

Modular robots are systems that can change its geometry or configuration when connecting more modules or when rearranging them in a different manner to perform a variety of tasks. Graph theory can be used to describe modular robots configurations, hence the possibility to determine the flexibility of the robot to move from one point to another. When the robot’s configurations are represented in a mathematical way, forward kinematics can be obtained

Extramedullary hematopoiesis within endothelial papillary hyperplasia (Masson?s pseudoangiosarcoma) of the tongue

We report the unique association of Masson?s pseudoangiosarcoma (endothelial papillary hyperplasia) and extramedullary hematopoiesis. The lesion was present as a violaceous nodule on the side of the tongue of a 78-year-old man with history of multiple myeloma and long-standing mild anemia. This association between a peculiar form of thrombus organization and extramedullary hematopoiesis has been reported previously only once, in an infant with a cranial hematoma, and raises interesting pathogenetic questions

Multibody Dynamics Model of a Human Hand for Haptics Interaction

In this paper we propose a strategy for modelling a human hand for Haptics interaction. The strategy consists in a parallel computing architecture that calculates the dynamics of a hand; this is accomplished by computing the dynamics of each finger in a parallel manner. In this approach multiple threads (e.g. haptics thread, graphics thread, collision detection thread, etc.) run concurrently and therefore we developed a synchronization mechanism for data exchange. We describe in detail the elements of the developed software

Tres pizarras con dibujos de época visigoda en la provincia de Salamanca

[ES] Junto a las pizarras con inscripciones numerales y escritura cursiva de tiempos visigodos conocidas en la región -Salamanca y Ávila fundamentalmente-, y desde hace años valoradas en su significado histórico, surge un nuevo grupo con escenas figuradas que parece ofrecer así mismo amplias posibilidades de interpretación.[EN] Along with slate slabs with numeric inscriptions and italic lettering of the visigoth period, well know in the region —Salamanca and Avila basically— and long praised in their historic significance, a new group of figurative scenes springs, which, likewise, seems to offer ample possibilities of interpretation