Stereo Viewing and Virtual Reality Technologies in Mobile Robot Teleguide

“This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder." “Copyright IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.” DOI: 10.1109/TRO.2009.2028765The use of 3-D stereoscopic visualization may provide a user with higher comprehension of remote environments in teleoperation when compared with 2-D viewing, in particular, a higher perception of environment depth characteristics, spatial localization, remote ambient layout, faster system learning, and decision performance. Works in the paper have demonstrated how stereo vision contributes to the improvement of the perception of some depth cues, often for abstract tasks, while it is hard to find works addressing stereoscopic visualization in mobile robot teleguide applications. This paper intends to contribute to this aspect by investigating the stereoscopic robot teleguide under different conditions, including typical navigation scenarios and the use of synthetic and real images. This paper also investigates how user performance may vary when employing different display technologies. Results from a set of test trials run on seven virtual reality systems, from laptop to large panorama and from head-mounted display to Cave automatic virtual environment (CAVE), emphasized few aspects that represent a base for further investigations as well as a guide when designing specific systems for telepresence.Peer reviewe

A Robotic arm for optical and gamma radwaste inspection

We propose Radibot, a simple and cheap robotic arm for remote inspection, which interacts with the radwaste environment by means of a scintillation gamma detector and a video camera representing its light (< 1 kg) payload. It moves vertically thanks to a crane, while the other three degrees of freedom are obtained by means of revolute joints. A dedicated algorithm allows to automatically choose the best kinematics in order to reach a graphically selected position, while still allowing to fully drive the arm by means of a standard videogame joypad

Mobile robotic teleguide based on video images

“This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder." “Copyright IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.” DOI: 10.1109/MRA.2008.929927Peer reviewe

Elemental fragmentation cross sections for a O-16 beam of 400 MeV/u kinetic energy interacting with a graphite target using the FOOT Delta E-TOF detectors

The study of nuclear fragmentation plays a central role in many important applications: from the study of Particle Therapy (PT) up to radiation protection for space (RPS) missions and the design of shielding for nuclear reactors. The FragmentatiOn Of Target (FOOT) collaboration aims to study the nuclear reactions that describe the interactions with matter of different light ions (like H-1, He-4, C-12, O-16) of interest for such applications, performing double differential fragmentation cross section measurements in the energy range of interest for PT and RPS. In this manuscript, we present the analysis of the data collected in the interactions of an oxygen ion beam of 400 MeV/u with a graphite target using a partial FOOT setup, at the GSI Helmholtz Center for Heavy Ion Research facility in Darmstadt. During the data taking the magnets, the silicon trackers and the calorimeter foreseen in the final FOOT setup were not yet available, and hence precise measurements of the fragments kinetic energy, momentum and mass were not possible. However, using the FOOT scintillator detectors for the time of flight (TOF) and energy loss (Delta E) measurements together with a drift chamber, used as beam monitor, it was possible to measure the elemental fragmentation cross sections. The reduced detector set-up and the limited available statistics allowed anyway to obtain relevant results, providing statistically significant measurements of cross sections eagerly needed for PT and RPS applications. Whenever possible the obtained results have been compared with existing measurements helping in discriminating between conflicting results in the literature and demonstrating at the same time the proper functioning of the FOOT Delta E-TOF system. Finally, the obtained fragmentation cross sections are compared to the Monte Carlo predictions obtained with the FLUKA software

Preliminary study on the correlation between accelerated current and dose in water for an electron-based LINAC

Purpose: Intraoperative electron radiotherapy (IOeRT) is considered the first clinical translation of FLASH with electrons. A crucial aspect is represented by the precise dose monitoring and measurement; to this aim, we propose a method fully based on Monte Carlo (MC) simulation that uses as input the beam current measurement and the beam optics simulation. To validate this approach, we chose the NOVAC11 (produced by Sordina IORT Technologies SpA) accelerator, which provides a well-studied model.Methods: We used FLUKA and FRED MC software to simulate in detail the geometry of the NOVAC11 and the coupled applicator usually adopted in clinical practice to deliver the dose in the surgical bed. The simulation results of the longitudinal and off-axis profiles and dose per pulse obtained in a water phantom with different applicators are compared to the experimental data.Results: A very good agreement not only for the relative dosimetry in both the longitudinal and off-axis profiles, with a gamma index pass rate of 100% with 3%/3 mm acceptance criteria, but also for the absolute dosimetry was obtained.Conclusion: The results completely validate the MC description of the system and provide a reliable evaluation of the dose per pulse and output factor with an accuracy of the order of few % for different sets of applicator diameters and lengths

Depth-enhanced mobile robot teleguide based on laser images

Original article can be found at: http://www.sciencedirect.com/ Copyright Elsevier3D stereoscopic visualization may provide a user with higher comprehension of remote environment in teleoperation when compared to 2D viewing. Works in the literature have addressed the contribution of stereo vision to improve perception of some depth cues often for abstract tasks, and it is hard to find contributions specifically addressing mobile robot teleguide. The authors of this paper have investigated stereoscopic viewing in mobile robot teleguide based on video images in a previous work and pointed out advantages of stereo viewing in this type of application as well as shortcomings inherent to the use of visual sensor, e.g. image transmission delay. The proposed investigation aims at testing mobile robot teleguide based on a different sensor: the laser sensor. The use of laser is expected to solve some problems related to visual sensor while maintaining the advantage of having stereoscopic visualization of a remote environment. A usability evaluation is proposed to assess system performance. The evaluation runs under the same setup of the previous study so to have an experimental outcome comparable to the previous one. The evaluation involves several users and two different 3D visualization technologies. The results show a strong improvement in users’ performance when mobile robot teleguide based on laser sensor is (depth-) enhanced by stereo viewing. Some differences are detected between the use of laser and visual sensor which are discussed.Peer reviewe

Augmented reality stereoscopic visualization for intuitive robot teleguide

This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder." “Copyright IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.This paper proposes a method to simultaneously and coherently present visual and laser sensors information through an augmented reality visualization interface further enhanced by stereoscopic viewing. The use of graphical objects is proposed to represent proximity measurements which are superimposed and suitably aligned to video information through image processing. This new methodology enables an operator to quickly comprehend scene layout and dynamics, and to respond in an accurate and timely manner. Therefore the human-robot interaction is expected to be intuitive, accurate and fast. The use of graphical elements to assist teleoperation, sometime discussed in the literature, is here proposed following a systematic approach and developed based on authors' previous works on stereoscopic teleoperation. The approach is experimented on a real telerobotic system where a user operates a robot located approximately 3,000 kilometers apart. The results of a pilot test were very encouraging. They showed simplicity and effectiveness of the approach proposed and represent a base for further investigations