Tomas Jilek

Color and Thermal Image Fusion for Augmented Reality in Rescue Robotics

At the beginning of this article, the authors address the main problems of todays remotely-operated reconnaissance robots. The reconnaissance robots Orpheus-AC, Orpheus-AC2 and Orpheus-Explorer, made in the Department of Control and Instrumentation (DCI), are then shortly described. Since all the described robotic systems use visual telepresence as the main control technique, visual information from the robots surroundings is essential for the operator. For this reason, the authors make a fusion of data from a Charge-Coupled Device (CCD) color camera, and a thermovision camera to provide the operator with data in all visibility conditions, such as complete darkness, fog, smoke, etc.

Cooperation between an unmanned aerial vehicle and an unmanned ground vehicle in highly accurate localization of gamma radiation hotspots

This article discusses the highly autonomous robotic search and localization of radiation sources in outdoor environments. The cooperation between a human operator, an unmanned aerial vehicle, and an unmanned ground vehicle is used to render the given mission highly effective, in accordance with the idea that the search for potential radiation sources should be fast, precise, and reliable. Each of the components assumes its own role in the mission; the unmanned aerial vehicle (in our case, a multirotor) is responsible for fast data acquisition to create an accurate orthophoto and terrain map of the zone of interest. Aerial imagery is georeferenced directly, using an onboard sensor system, and no ground markers are required. The unmanned aerial vehicle can also perform rough radiation measurement, if necessary. Since the map contains three-dimensional information about the environment, algorithms to compute the spatial gradient, which represents the rideability, can be designed. Based on the primary aerial map, the human operator defines the area of interest to be examined by the applied unmanned ground vehicle carrying highly sensitive gamma-radiation probe/probes. As the actual survey typically embodies the most time-consuming problem within the mission, major emphasis is put on optimizing the unmanned ground vehicle trajectory planning; however, the dual-probe (differential) approach to facilitate directional sensitivity also finds use in the given context. The unmanned ground vehicle path planning from the pre-mission position to the center of the area of interest is carried out in the automated mode, similarly to the previously mentioned steps. Although the human operator remains indispensable, most of the tasks are performed autonomously, thus substantially reducing the load on the operator to enable them to focus on other actions during the search mission. Although gamma radiation is used as the demonstrator, most of the proposed algorithms and tasks are applicable on a markedly wider basis, including, for example, chemical, biological, radiological, and nuclear missions and environmental measurement tasks.

Multispectral data fusion for robotic reconnaissance and mapping

The aim of the paper is to describe the data-fusion from optical sensors for mobile robotics reconnaissance and mapping. Data are acquired by stereo pair of CCD cameras, stereo pair of thermal imagers, and TOF (time-of-flight) camera. The fusion is realized by means of spatial data from a TOF camera to ensure “natural” representation of a robots environment; thus, the thermal and CCD camera data are comprised in one stereo image presented to a binocular, head-mounted display. The data acquisition is performed using a sensor head, which is placed on an Orpheus-X3 robot; both the head and the robot were developed by our working group. After the geometrical calibration of each sensor, the positions of the sensors in 6DOFs are computed. The corresponding data from the CCD camera and the thermal imager are subsequently determined via homogeneous and perspective transformations. The result consists in an image containing aligned data from the CCD camera and the thermal imager for each eye. TOF camera calibration and its impact to the precision of fusion is described. Although the fusion is used for two different tasks - automatic environment mapping and visual telepresence, the utilised calibration and fusion algorithms are, in principle, the same.

Multi-robot system for disaster area exploration

CASSANDRA robotic system developed at LTR s.r.o. company and Brno University of Technology is described. The system contains an operator’s station controlled with one operator and a couple of robots – small and big ground robots, flying robots (quadrocopters), and mapping robot. The robots are primarily controlled by the operator with an advanced user interface with visual telepresence and augmented reality. Nevertheless, the robots include the possibility of semiautonomous operation based on self-localisation. The user interface consists of a computer, joypad, head-mounted display with inertial head-tracker, communication device, and Cassandra software developed by our team in Microsoft .NET. Orpheus class robots are described in the text. The robots are made to be reliable and to be able to work in extreme conditions, they are tested by a series of MIL-STD military tests for environmental parameters, EMC, vibrations and shocks, contamination/decontamination, etc. Orpheus-X3 is a general US&R robot with enhanced victim search capabilities, Orpheus-HOPE is made for water contamination measurements, Orpheus-AC2 is a ruggedized version for environmental parameter measurement. Two flying drones developed completely by our team are described, as well as EnvMap mapping robot for realtime construction of spatial digital maps with texture mapping. All the robots can be controlled with the help of visual telepresence and augmented reality – that makes robot control much more intuitive, and lets the rescuer concentrate on the mission itself. The control station may be used as a self-containing wearable system. The fusion system with multispectral measurement containing tricolor cameras, thermal imagers and TOF camera is described.

Multi-robotic Area Exploration for Environmental Protection

Area guarding, exploration, and environmental measurement constitute both major necessities and open challenges for current robotics.

Radiation intensity mapping in outdoor environments using a mobile robot with RTK GNSS

Two gamma-radiation distribution field measurement experiments are described in the paper. Because of principally dangerous nature of gamma-radiation, the idea was to extensively use robotic systems and automation to minimize human exposure to radiation. The experiment setup as well as Orpheus robotic system are described. Algorithm to autonomously navigate the robot based on RTK GNSS in predefined area is presented. The algorithm was exclusively developed for Orpheus robot, considering its tank-like drive configuration.

Fast total least squares vectorization

This paper proposes a novel algorithm for the vectorization of ordered sets of points, named Fast Total Least Squares (FTLS) vectorization. The emphasis was put on low computational complexity, which allows it to be run online on a mobile device at a speed comparable to the fastest algorithms, such as the Douglas–Peucker (DP) algorithm, while maintaining a much higher quality of the approximation. Our approach is based on the total least squares method, therefore all the points from the cloud contribute to its approximation. This leads to better utilization of the information contained in the point cloud, compared to those algorithms based on point elimination, such as DP. Several experiments and performance comparisons are presented to demonstrate the most important attributes of the FTLS algorithm.

Security of remote management of embedded systems running MikroTik RouterOS operating system using proprietary protocols

This paper deals with proprietary communication protocols that are implemented in the MikroTik RouterOS operating system. These communication protocols are specially designed for remote management of embedded systems that run with this operating system. These protocols are closed and thus they have not a publicly accessible documentation. In this paper the principles of their functions that are identified on the basis of realized communication analyses are described. Security risks that are associated with the use of these communication protocols are also analyzed in the paper. Attack that uses conceptual bug in the design one of these communication protocols is demonstrated on a real example. Full and unlimited access to embedded system that runs with this operating system can be obtained with this attack.

Unified Storage for Laser Scanner Data

The main goal of this paper is to show a way to resolve interoperability of more different laser proximity scanners into a mapping engine. The idea is to make a software layer with unified data approach to be able to access laser scanner data from different 2D or 3D proximity scanners in unified way. Presented work is a part of project with the aim to make widely accessible data for self-localization algorithms assessment in mobile robotics. All the described algorithms, source code and scanner data will be accessible on project web-page http://www.mapping.uamt.feec.vutbr.cz .