1,721,017 research outputs found
Tactile sensors for robotic applications
Full text linkIn recent years, tactile sensing has become a key enabling technology to implement complex tasks by using robotic systems [...]
Validating DLO models from shape observation
Full text linkIn this paper, the problem of fitting the model of deformable linear objects from the observation of the shape under the effect of known external forces like gravity is taken into account. The model of the deformable linear object is based on dynamic splines, allowing to obtain a reliable prediction of the object behavior while preserving a suitable efficiency and simplicity of the model. The object shape is measured by means of a calibrated vision system, and a fitting between the observed shape and the theoretical model is defined for validation. Experiments are executed in different conditions, showing the reliability of the proposed spline-based model
Optical Force/Tactile Sensors for Robotic Applications
Full text linkNowadays, robotic systems use tactile sensing as a key enabling technology to implement complex tasks. For example, manipulation and grasping problems strongly depend on the physical and geometrical characteristics of the objects; in fact, objects may be deformable or change their shape when in contact with the robot or the environment. For this reason, often, robots end effectors are equipped with sensorized fingers which can estimate the objects' features, forces, and contact locations. This is useful in a safe and efficient physical Human-Robot Interaction (pHRI) to perform cooperation and co-manipulation tasks while limiting damage from accidental impacts
Vision-Based Robotic Solution for Wire Insertion with an Assigned Label Orientation
Full text linkThis paper tackles the problem of wire insertion in switchgear assembly according to the current regulations. In particular, the wire connections require that the wire label has to be oriented facing up in order to simplify and speed up testing and maintenance of the switchgear. The proposed approach exploits the a priori knowledge of the scenario with a calibrated RGB camera and a robotic arm to estimate both wire end pose and label position. The procedure combines several techniques (gradient base, trained classifier and stereo vision) to elaborate standard images in order to extract some wire features related to its shape and label. Specific frames are fixed according to estimated features and then used to correctly complete the task by using a robotic system. Experiments are reported to verify the effectiveness of the proposed approach
An Intelligent System for Human Intent and Environment Detection Through Tactile Data
No full textThe tackled application aims at demonstrating the effectiveness of using tactile sensors for multiple purposes at the same time. In particular, tactile data are exploited for: the estimation of a wire diameter by using a previously trained classifier; teaching the robot new wire routing trajectories in case of unknown grasped wires; stopping the autonomous execution of previously learned trajectories to avoid damages due to possible wire entanglements
Multiphysics Simulation for the Optimization of an Optoelectronic-Based Tactile Sensor
No full textRobotic systems are more and more present in various contexts such as industrial, domestic, logistic, health-care, and others. For this reason, robots are being used for increasingly complex tasks which require skills like dexterity and precision. These capabilities are achieved by means of sensory systems that give that robot the perception of the environment. Sensors, before being produced and distributed, need to be suitably designed in order to fulfil the specifics that a task requires. During the design process, simulation methods are really important to analyze the characteristics of a designed product before actually producing it, so as to avoid waste of time and money. This paper aims at proposing a method for simulating a tactile sensor based on optoelectronic technology considering both the optical and mechanical interfaces, as well as their coupling. Also, it exploits both simulation and experiment results in order to discuss the best choice for the shape to use for the realization of reflective cells
Comparison of wind LIDAR measurements with predictions from airport data
No full textThe prediction of the mean and extreme wind climate at a site from airport historical data contains intrinsic errors coming from the not necessarily good quality of the original data, from the approximations adopted when defining orography and roughness at the sites of measurement and at the site of interest, from the possible presence of sheltering effects at the site of measurement and from the approximations embedded in the mathematical models used for transferring the measured data to the site of interest.
In this paper the wind velocities predicted at e site from airport measurement are compared with wind LIDAR measurements, with the purpose of quantifying inaccuracies and possibly detecting their causes
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
- …
