Search results for "Robot"
showing 10 items of 1036 documents
Gastrointestinal helminths found in the three freshwater turtles (Erymnochelys madagascariensis, Pelomedusa subrufa and Pelusios castanoides) from An…
2007
Abstract We conducted a survey of the presence, prevalence and diversity of gastrointestinal helminths in faecal samples and stomach contents of three turtle species, — Erymnochelys madagascariensis (Chelonia: Podocnemididae), Pelomedusa subrufa and Pelusios castanoides (Chelonia: Pelomedusidae), — from several localities in Madagascar. Four nematode species were detected: Atractis chabaudi, Camallanus chelonius, Falcaustra pelusios, and Spiroxys sp. E. madagascariensis, with all four species, had the greatest helminth diversity. A. chabaudi was the community’s core species, whereas Spiroxys sp. was a satellite species. Only two species (A. chabaudi and Spiroxys sp.) were found in P. subruf…
Study of the first reported nest of loggerhead sea turtle, Caretta caretta, in the Spanish Mediterranean coast
2002
We summarize all the data of nest placement, incubation period, emergence of hatchlings and nest study of the first reported nesting event of a loggerhead turtle Caretta caretta (Reptilia: Cheloniidae) in the Spanish Mediterranean coast. The nest was laid in a beach of Almería province (south-east Spain) in July 2001. The incubation period was 58 days. Forty-two hatchlings emerged from a total of 97 eggs laid. Future beach surveys will determine whether this is a sporadic nesting event or whether loggerheads nest frequently in these coasts.
El marcaje revela un intercambio limitado de inmaduros de tortuga boba (<i>Caretta caretta</i>) entre regiones en el Mediterráneo occiden…
2008
Exchange of immature loggerhead sea turtles (Caretta caretta) between the northern and southern regions of the western Mediterranean was investigated using data obtained from several Spanish tagging programmes. Tagged turtles ranged in straight carapace length from 23.0 to 74.0 cm. Thirty-six turtles were recaptured after an average interval of 390.5±462.6 days (SD). As the mean dispersal distance (MDD) of a turtle population that spreads over the western Mediterranean would stabilize after 117 days (CI 95%: 98 to 149), two analyses were conducted that included data from turtles recaptured after 98 and 149 days respectively. In both analyses, turtles were recaptured more often than expected…
Mechanical Bistable Structures for Microrobotics and Mesorobotics from Microfabrication to Additive Manufacturing
2018
International audience; The use of mechanical bistable structures in the design of microrobots and mesorobots has many advantages especially for flexible robotic structures. However, depending on the fabrication technology used, the adequacy of theoretical and experimental mechanical behaviors can vary widely. In this paper, we present the manufacturing results of bistable structures made with two extensively used contemporary technologies: MEMS and FDM additive manufacturing. Key issues of these fabrication technologies are discussed in the context of microrobotics and mesorobotics applications.
Evaluation of a Completely Robotized Neurosurgical Operating Microscope
2012
BACKGROUND Operating microscopes are essential for most neurosurgical procedures. Modern robot-assisted controls offer new possibilities, combining the advantages of conventional and automated systems. OBJECTIVE We evaluated the prototype of a completely robotized operating microscope with an integrated optical coherence tomography module. METHODS A standard operating microscope was fitted with motors and control instruments, with the manual control mode and balance preserved. In the robot mode, the microscope was steered by a remote control that could be fixed to a surgical instrument. External encoders and accelerometers tracked microscope movements. The microscope was additionally fitted…
Conversion to Open Surgery During Minimally Invasive Right Colectomy for Cancer: Results from a Large Multinational European Study
2023
: Background: The risk of conversion to open surgery is inevitably present during any minimally invasive colorectal surgical procedure. Conversions have been associated with adverse postoperative and oncologic outcomes. No previous study has evaluated the specific causes and consequences of conversion during a minimally invasive right colectomy (MIS-RC). Materials and Methods: We analyzed the Minimally invasivE surgery for oncologic Right ColectomY (MERCY) study database including patients who underwent laparoscopic or robotic RC because of colon cancer between 2014 and 2020. Descriptive analyses were performed to determine the different reasons for conversion. Uni- and multivariate logisti…
State Estimation of a Mobile Manipulator via Non-uniformly Sampled Position Measurements
2011
Abstract We derive an exact deterministic nonlinear estimator to compute the continuous state of a nonlinear time-varying system based on discrete, non uniformly time spaced, state measurements. The system consists of a robot arm mounted on a mobile non holonomic vehicle. The paper also discusses the effect on the estimation error of a bounded input additive noise.
Architecture to Serve Disabled and Elderly
2013
We propose an architecture (discussed in the context of a dressing and cleaning application for impaired and elderly persons) that combines a cognitive framework that generates motor commands with the MOSAIC architecture which selects the right motor command according to the proper context. The ambition is to have robots able to understand humans intentions (dressing or cleaning intentions), to learn new tasks only by observing humans, and to represent the world around it by using conceptual spaces. The cognitive framework implements the learning by demonstration paradigm and solves the related problem to map the observed movement into the robot motor system. Such framework is assumed to wo…
Evolving mobile robots in simulated and real environments.
1995
The problem of the validity of simulation is particularly relevant for methodologies that use machine learning techniques to develop control systems for autonomous robots, as, for instance, the artificial life approach known as evolutionary robotics. In fact, although it has been demonstrated that training or evolving robots in real environments is possible, the number of trials needed to test the system discourages the use of physical robots during the training period. By evolving neural controllers for a Khepera robot in computer simulations and then transferring the agents obtained to the real environment we show that (a) an accurate model of a particular robot-environment dynamics can …
Motion Analysis for Dynamic 3D Scene Reconstruction and Understanding
2017
This thesis studies the problem of dynamic scene 3D reconstruction and understanding using a calibrated 2D-3D camera setup mounted on a mobile platform via the analysis of objects' motions. For static scenes, the sought 3D map reconstruction can be obtained by registering the point cloud sequence. However, with dynamic scenes, we require a prior step of moving object elimination, which yields to the motion detection and segmentation problems. We provide solutions for the two practical scenarios, namely the known and unknown camera motion cases, respectively. When camera motion is unknown, our 3D-SSC and 3D-SMR algorithms segment the moving objects by analysing their 3D feature trajectories.…