889 research outputs found
Autonomous robotic system for thermographic detection of defects in upper layers of carbon fiber reinforced polymers
Carbon Fiber Reinforced Polymers (CFRPs) are composites whose interesting properties, like high strength-to-weight ratio and rigidity, are of interest in many industrial fields. Many defects affecting their production process are due to the wrong distribution of the thermosetting polymer in the upper layers. In this work, they are effectively and efficiently detected by automatically analyzing the thermographic images obtained by Pulsed Phase Thermography (PPT) and comparing them with a defect-free reference. The flash lamp and infrared camera needed by PPT are mounted on an industrial robot so that surfaces of CFRP automotive components, car side blades in our case, can be inspected in a series of static tests. The thermographic image analysis is based on local contrast adjustment via UnSharp Masking (USM) and takes also advantage of the high level of knowledge of the entire system provided by the calibration procedures. This system could replace manual inspection leading to a substantial increase in efficiency
Fast and Robust Detection of Fallen People from a Mobile Robot
This paper deals with the problem of detecting fallen people lying on the
floor by means of a mobile robot equipped with a 3D depth sensor. In the
proposed algorithm, inspired by semantic segmentation techniques, the 3D scene
is over-segmented into small patches. Fallen people are then detected by means
of two SVM classifiers: the first one labels each patch, while the second one
captures the spatial relations between them. This novel approach showed to be
robust and fast. Indeed, thanks to the use of small patches, fallen people in
real cluttered scenes with objects side by side are correctly detected.
Moreover, the algorithm can be executed on a mobile robot fitted with a
standard laptop making it possible to exploit the 2D environmental map built by
the robot and the multiple points of view obtained during the robot navigation.
Additionally, this algorithm is robust to illumination changes since it does
not rely on RGB data but on depth data. All the methods have been thoroughly
validated on the IASLAB-RGBD Fallen Person Dataset, which is published online
as a further contribution. It consists of several static and dynamic sequences
with 15 different people and 2 different environments
Brain-Computer Interface meets ROS: A robotic approach to mentally drive telepresence robots
This paper shows and evaluates a novel approach to integrate a non-invasive
Brain-Computer Interface (BCI) with the Robot Operating System (ROS) to
mentally drive a telepresence robot. Controlling a mobile device by using human
brain signals might improve the quality of life of people suffering from severe
physical disabilities or elderly people who cannot move anymore. Thus, the BCI
user is able to actively interact with relatives and friends located in
different rooms thanks to a video streaming connection to the robot. To
facilitate the control of the robot via BCI, we explore new ROS-based
algorithms for navigation and obstacle avoidance, making the system safer and
more reliable. In this regard, the robot can exploit two maps of the
environment, one for localization and one for navigation, and both can be used
also by the BCI user to watch the position of the robot while it is moving. As
demonstrated by the experimental results, the user's cognitive workload is
reduced, decreasing the number of commands necessary to complete the task and
helping him/her to keep attention for longer periods of time.Comment: Accepted in the Proceedings of the 2018 IEEE International Conference
on Robotics and Automatio
On the comparison of regulatory sequences with multiple resolution Entropic Profiles
Enhancers are stretches of DNA (100-1000 bp) that play a major role in development gene expression, evolution and disease. It has been recently shown that in high-level eukaryotes enhancers rarely work alone, instead they collaborate by forming clusters of cis-regulatory modules (CRMs). Although the binding of transcription factors is sequence-specific, the identification of functionally similar enhancers is very difficult and it cannot be carried out with traditional alignment-based techniques
Semantic models of scenes and objects for service and industrial robotics
What may seem straightforward for the human perception system is still challenging for robots. Automatically segmenting the elements with highest relevance or salience, i.e. the semantics, is non-trivial given the high level of variability in the world and the limits of vision sensors. This stands up when multiple ambiguous sources of information are available, which is the case when dealing with moving robots. This thesis leverages on the availability of contextual cues and multiple points of view to make the segmentation task easier. Four robotic applications will be presented, two designed for service robotics and two for an industrial context. Semantic models of indoor environments will be built enriching geometric reconstructions with semantic information about objects, structural elements and humans. Our approach leverages on the importance of context, the availability of multiple source of information, as well as multiple view points showing with extensive experiments on several datasets that these are all crucial elements to boost state-of-the-art performances.
Furthermore, moving to applications with robots analyzing object surfaces instead of their surroundings, semantic models of Carbon Fiber Reinforced Polymers will be built augmenting geometric models with accurate measurements of superficial fiber orientations, and inner defects invisible to the human-eye. We succeeded in reaching an industrial grade accuracy making these models useful for autonomous quality inspection and process optimization. In all applications, special attention will be paid towards fast methods suitable for real robots like the two prototypes presented in this thesis
RUR53: an Unmanned Ground Vehicle for Navigation, Recognition and Manipulation
This paper proposes RUR53: an Unmanned Ground Vehicle able to autonomously
navigate through, identify, and reach areas of interest; and there recognize,
localize, and manipulate work tools to perform complex manipulation tasks. The
proposed contribution includes a modular software architecture where each
module solves specific sub-tasks and that can be easily enlarged to satisfy new
requirements. Included indoor and outdoor tests demonstrate the capability of
the proposed system to autonomously detect a target object (a panel) and
precisely dock in front of it while avoiding obstacles. They show it can
autonomously recognize and manipulate target work tools (i.e., wrenches and
valve stems) to accomplish complex tasks (i.e., use a wrench to rotate a valve
stem). A specific case study is described where the proposed modular
architecture lets easy switch to a semi-teleoperated mode. The paper
exhaustively describes description of both the hardware and software setup of
RUR53, its performance when tests at the 2017 Mohamed Bin Zayed International
Robotics Challenge, and the lessons we learned when participating at this
competition, where we ranked third in the Gran Challenge in collaboration with
the Czech Technical University in Prague, the University of Pennsylvania, and
the University of Lincoln (UK).Comment: This article has been accepted for publication in Advanced Robotics,
published by Taylor & Franci
Flash: Fast and Light Motion Prediction for Autonomous Driving with Bayesian Inverse Planning and Learned Motion Profiles
Motion prediction of road users in traffic scenes is critical for autonomous
driving systems that must take safe and robust decisions in complex dynamic
environments. We present a novel motion prediction system for autonomous
driving. Our system is based on the Bayesian inverse planning framework, which
efficiently orchestrates map-based goal extraction, a classical control-based
trajectory generator and an ensemble of light-weight neural networks
specialised in motion profile prediction. In contrast to many alternative
methods, this modularity helps isolate performance factors and better interpret
results, without compromising performance. This system addresses multiple
aspects of interest, namely multi-modality, motion profile uncertainty and
trajectory physical feasibility. We report on several experiments with the
popular highway dataset NGSIM, demonstrating state-of-the-art performance in
terms of trajectory error. We also perform a detailed analysis of our system's
components, along with experiments that stratify the data based on behaviours,
such as change lane versus follow lane, to provide insights into the challenges
in this domain. Finally, we present a qualitative analysis to show other
benefits of our approach, such as the ability to interpret the outputs
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