Ludek Zalud

Robust detection of shady and highlighted roads for monocular camera based navigation of UGV

This paper addresses the problem of UGV navigation in various environments and lightning conditions. Previous approaches use a combination of different sensors, or work well, only in scenarios with noticeable road marking or borders. Our robot is used for chemical, nuclear and biological contamination measurement. Thus, to avoid complications with decontamination, only a monocular camera serves as a sensor since it is already equipped. In this paper, we propose a novel approach - a fusion of frequency based vanishing point estimation and probabilistically based color segmentation. Detection of a vanishing point, is based on the estimation of a texture flow, produced by a bank of Gabor wavelets and a voting function. Next, the vanishing point defines the training area, which is used for self-supervised learning of color models. Finally, road patches are selected by measuring of the roadness score. A few rules deal with dark cast shadows, overexposed highlights and adaptivity speed. In addition to the robustness of our system, it is easy-to-use since no calibration is needed.

Remote-controlled robotic platform ORPHEUS as a new tool for detection of bacteria in the environment

Remote‐controlled robotic systems are being used for analysis of various types of analytes in hostile environment including those called extraterrestrial. The aim of our study was to develop a remote‐controlled robotic platform (ORPHEUS‐HOPE) for bacterial detection. For the platform ORPHEUS‐HOPE a 3D printed flow chip was designed and created with a culture chamber with volume 600 μL. The flow rate was optimized to 500 μL/min. The chip was tested primarily for detection of 1‐naphthol by differential pulse voltammetry with detection limit (S/N = 3) as 20 nM. Further, the way how to capture bacteria was optimized. To capture bacterial cells (Staphylococcus aureus), maghemite nanoparticles (1 mg/mL) were prepared and modified with collagen, glucose, graphene, gold, hyaluronic acid, and graphene with gold or graphene with glucose (20 mg/mL). The most up to 50% of the bacteria were captured by graphene nanoparticles modified with glucose. The detection limit of the whole assay, which included capturing of bacteria and their detection under remote control operation, was estimated as 30 bacteria per μL.

Fusion of thermal imaging and CCD camera-based data for stereovision visual telepresence

The aim of this paper is to describe the fusion of data acquired from a CCD camera and a thermal imager. 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 color-related 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. The head contains five matrix sensors: a pair of CCD cameras, a pair of thermal imagers, and one TOF camera. 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.

Laser proximity scanner correlation based method for cooperative localization and map building

This article is concerned with an autonomous robot self-localization, that is the first step of robot navigation. Only if the robot knows where it is relative to a suitable coordinate frame, can it plan its trajectory, and plan the whole mission. The next important part of the autonomous mobile robotic system is a map of the environment. Many self-localization modules suppose the map of the neighbourhood is known. In this paper a method for cooperative robot map building and robot pose-estimation is presented. One SICK Laser proximity scanner is used as the only input sensor for the method. The method is based on angle, x and y histograms and cross-correlation function. As a localization quality estimation, robot evidence grids and modified evidence grids methods are used. The output from the method is a two-dimensional map of the robots environment and the actual position of the robot in this map. The method is programmed in GNU C programming language and tested on UTAR (Universal Teleprezence and Autonomous Robot) system. Results of practical experiments in a real environment are presented.

CASSANDRA - heterogeneous reconnaissance robotic system for dangerous environments

Robotic system consisting of multiple different remotely operated robots and one operators station is described. The system consists of two small robots, two bigger robots, and one flying machine, while each of them has different features to form balanced system for variety of missions. The robots, as well as the whole system and its possible mission configurations are described in the article. Great attention is paid to the communication subsystem, i.e. not only robot-to-operators station communication, but also signal retranslation.

Robotic 3D scanner as an alternative to standard modalities of medical imaging

There are special medical cases, where standard medical imaging modalities are able to offer sufficient results, but not in the optimal way. It means, that desired results are produced with unnecessarily high expenses, with redundant informations or with needless demands on patient. This paper deals with one special case, where information useful for examination is the body surface only, inner sight into the body is needless. New specialized medical imaging device is developed for this situation.In the Introduction section, analysis of presently used medical imaging modalities is presented, which declares, that no available imaging device is best fitting for mentioned purposes. In the next section, development of the new specialized medical imaging device is presented, and its principles and functions are described. Then, the parameters of new device are compared with present ones. It brings significant advantages comparing to present imaging systems.

INTEGRATION OF 3D PROXIMITY SCANNER TO ORPHEUS ROBOTIC SYSTEM

Abstract Orpheus mobile robot is a teleoperated device primarily designed for remote exploration of hazardous places and rescue missions. The robot is able to operate both indoors and outdoors, is made to be durable and reliable. The device is controlled through advanced user interface with joystick and head mounted display with inertial head movement sensor. To increase the systems operability in difficult conditions (fog, smoke, dark), 3D proximity scanner controlled by on-board processor through Ethernet connection was integrated to it. The scanner also represents a step towards semi-autonomous mode of the robot.

Orpheus Reconnissance Robots

Orpheus robotic system projects, including experimental Orpheus-X2 and Orpheus-EB, are presented. Novel member of Orpheus family named Orpheus-AC is presented. Orpheus-AC is a ruggedized teleoperated robot made for chemical and nuclear reconnaissance and was made at our department for VOP-026, Sternberk, s. p. company. It may be operated wireless or by wire, and fulfills military standards regarding EMC, environmental and special parameters.

Robot mapping with range camera, CCD cameras and thermal imagers.

This paper describes a multispectral data fusion system for real-time telepresence and digital mapping applicable in reconnaissance robotics. The system was developed by our team for CASSANDRA, a robotic group comprising several robots with different features controllable from a single operator station. Special emphasis is put on cooperative mapping and problems arising from the fact that each robot has distinct sensors and computing capabilities; at the same time, however, it is important to stress that all the robots can supply valuable data to the global map. The system is currently able to process distance data, color data, and thermal information, but it is also prepared for extension such that other parts of the electromagnetic spectrum (e.g., the near infrared region) or mission-specific (e.g., radiation) data can be easily added to the map. The fusion quality and map features were studied both theoretically and via field experiments. The data acquisition is performed using a sensor head placed on an Orpheus-X3 robot; both the head and the robot were developed by our working group. The head contains five matrix sensors: a pair of CCD cameras, a pair of thermal imagers, and one TOF camera.

ARGOS - System for Heterogeneous Mobile Robot Teleoperation

ARGOS (advanced robotic graphical operation system) for teleoperation of various mobile robots through sensory supported visual telepresence is presented. Two robots -Orpheus and Hermes - made on Department of Control and Instrumentation (DCI) are described as examples of systems with different features and capabilities that may be controlled through ARGOS. Integration of 3D scanners to the robots and their measurement to ARGOS system is presented. Data fusion of CCD color camera data, thermovision data and 3D proximity data through extended 3D robot evidence grids is described