Web based education tool for neural network robot controlJure Čas
, Darko Hercog
, Riko Šafarič
, izvirni znanstveni članek
Opis: This paper describes the application for teleoperations of the SCARA robot via the internet. The SCARA robot is used by students of mehatronics at the University of Maribor as a remote educational tool. The developed software consists of two parts i.e. the continuous neural network sliding mode controller (CNNSMC) and the graphical user interface (GUI). Application is based on two well-known commercially available software packages i.e. MATLAB/Simulink and LabVIEW. Matlab/Simulink and the DSP2 Library for Simulink are used for control algorithm development, simulation and executable code generation. While this code is executing on the DSP-2 Roby controller and through the analog and digital I/O lines drives the real process, LabVIEW virtual instrument (VI), running on the PC, is used as a user front end. LabVIEW VI provides the ability for on-line parameter tuning, signal monitoring, on-line analysis and via Remote Panels technology also teleoperation. The main advantage of a CNNSMC is the exploitation of its self-learning capability. When friction or an unexpected impediment occurs for example, the user of a remote application has no information about any changed robot dynamic and thus is unable to dispatch it manually. This is not a control problem anymore because, when a CNNSMC is used, any approximation of changed robot dynamic is estimated independently of the remote's user.
Ključne besede: LabVIEW, Matlab/Simulink, neural network control, remote educational tool
Objavljeno: 19.07.2017; Ogledov: 86; Prenosov: 4
Celotno besedilo (792,88 KB)
Interface between macro and nano worldsGregor Škorc
, Riko Šafarič
, David Lukman
, Sirhiy Ivanovich Protsenko
, Simon Zapusek
, 2010, izvirni znanstveni članek
Opis: This paper describes the design of a nanorobotic application which includes: nanorobotic arm, Akiyama sensor system, a vacuum chamber, and an interface tools for the nanorobotic hardware developed using C++ and VRML languages in order to create a desktop virtual-reality environment which improves visualisation and prevents collision of the nanomanipulator hardware with the associated workspace. The presented experiment shows how the used man-machine interface could be used for communication between macro and micro/nano worlds.
Ključne besede: nanorobotics, virtual-reality, sensors system
Objavljeno: 19.07.2017; Ogledov: 88; Prenosov: 4
Celotno besedilo (1,70 MB)
Control and robotics remote laboratory for engineering educationRiko Šafarič
, Mitja Truntič
, Darko Hercog
, Gregor Pačnik
, 2005, izvirni znanstveni članek
Opis: The new tools for education of engineering emerged and one of the most promising is a remote rapid control prototyping (RRCP), which is very useful also for control and robotics development in industry and in education. Examples of introductory remote control and simple robotic. courses with integrated hand, on experiments are presented in the paper. The aim o/: integration of remote hand on experiments into control and/or robotics course is to minimize the gap between the theory and practice to teach students the use of RRCP and to decrease the education costs. Developed RRCP experiments are based on MATLAB/Simulink, xPC target, custom developed embedded target for DSP-2 controller and LabVIEW virtual instrument.
Ključne besede: education of control and robotics, rapid prototyping, remote engineering
Objavljeno: 19.07.2017; Ogledov: 88; Prenosov: 6
Celotno besedilo (1,80 MB)
Growth dynamics and reproductive activity of annual shoots in the walnut cultivar 'Elit'Anita Solar
, Mitja Solar
, Franci Štampar
, 2005, izvirni znanstveni članek
Opis: An architectural analysis of a fruiting branch in the Slovenian variety 'Elit' was conducted during three successive years. The fruit bearing branch was constructed of a three-year-old parent shoot plus all corresponding two-year-old shoots and annual shoots (1Y). The construction of the bearing branch during the time caused a statistically significant increase in the number of annual shoots. The basal diameter and the length of 1Y significantly depended on a year whereas their angles did not. In spite of decreasing length of 1Y, the number of vegetative buds per shoot increased from the first to the third year of observations. The number of nodes was closely correlated with the length of the shoots. Activity points on the 1Y were most often on the apical two or three nodes, what was expressed by a marked acrotony. The number of active points varied as the tree matured. The ratio fruit bearing 1Y ž total 1Y was 0.47 in year 1; 0.18 in year 2; 0.74 in year 3. It points to the slightly alternance. As the tree grew the number of flowering buds per 1Y as well as the number of female flowers per 1Y increased. The results of the three-year-long research show some growth and development rules in the walnut cultivar 'Elit', however, they do not allow a reliable prediction of the following activities. We assume that this will be possible after another three-year-long analysis, with the help of the Hidden Mark Model.
Ključne besede: Juglans regia L., tree architecture, fruiting branch, vegetative growth, bearing potentials, shoots, statistical modelling, Hidden Mark Model
Objavljeno: 13.07.2017; Ogledov: 91; Prenosov: 6
Celotno besedilo (284,30 KB)
Citation context and impact of 'sleeping beauties' in paediatric researchJernej Završnik
, Peter Kokol
, Stefano Del Torso
, Helena Blažun
, 2016, pregledni znanstveni članek
Opis: Objectives: ‘Sleeping beauties’, i.e. publications that are not cited for a long while, present interesting findings in science. This study analysed the citation trends of sleeping beauties in paediatric research.
Methods: The study used bibliometric software to analyse the papers citing sleeping beauties in paediatric research, to understand the context in which paediatric sleeping beauties were finally cited and the impact of these sleeping beauties on paediatric research.
Results: Two paediatric sleeping beauties, addressing medical homes and the transition from paediatric to adult health care, respectively, awakened in response to organizational needs. Both presented novel concepts of paediatric service organization that became important because of an increased need for optimization of services.
Conclusion: All sleeping beauties bring new knowledge that becomes important only after several years. Paediatric sleeping beauties exhibited unique characteristics; however, their presence in paediatric research shows that knowledge acquisition in paediatrics resembles that in other disciplines.
Ključne besede: sleeping beauties, bilbliometrics, citation analysis, pediatrics, paediatrics, publications, research
Objavljeno: 13.07.2017; Ogledov: 80; Prenosov: 4
Celotno besedilo (573,45 KB)
Biomechanical characteristics of skeletal muscles and associations between running speed and contraction time in 8- to 13-year-old childrenJernej Završnik
, Rado Pišot
, Boštjan Šimunič
, Peter Kokol
, Helena Blažun
, 2017, izvirni znanstveni članek
Opis: Objective: To investigate associations between running speeds and contraction times in 8- to 13-year-old children.
Method: This longitudinal study analyzed tensiomyographic measurements of vastus lateralis and biceps femoris muscles’ contraction times and maximum running speeds in 107 children (53 boys, 54 girls). Data were evaluated using multiple correspondence analysis.
Results: A gender difference existed between the vastus lateralis contraction times and running speeds. The running speed was less dependent on vastus lateralis contraction times in boys than in girls. Analysis of biceps femoris contraction times and running speeds revealed that running speeds of boys were much more structurally associated with contraction times than those of girls, for whom the association seemed chaotic.
Conclusion: Joint category plots showed that contraction times of biceps femoris were associated much more closely with running speed than those of the vastus lateralis muscle. These results provide insight into a new dimension of children’s development.
Ključne besede: children, tensiomyography, running speed, contraction time, skelet muscle, motor development
Objavljeno: 13.07.2017; Ogledov: 81; Prenosov: 6
Celotno besedilo (454,48 KB)
Lossless geometry compression through changing 3D coordinates into 1DYongkui Liu
, Lijun He
, Peng-jie Wang
, Linghua Li
, Borut Žalik
, 2013, izvirni znanstveni članek
Opis: A method of lossless geometry compression on the coordinates of the vertexes for grid model is presented. First, the 3D coordinates are pre-processed to be transformed into a specific form. Then these 3D coordinates are changed into 1D data by making the three coordinates of a vertex represented by only a position number, which is made of a large integer. To minimize the integers, they are sorted and the differences between two adjacent vertexes are stored in a vertex table. In addition to the technique of geometry compression on coordinates, an improved method for storing the compressed topological data in a facet table is proposed to make the method more complete and efficient. The experimental results show that the proposed method has a better compression rate than the latest method of lossless geometry compression, the Isenburg-Lindstrom-Snoeyink method. The theoretical analysis and the experiment results also show that the important decompression time of the new method is short. Though the new method is explained in the case of a triangular grid, it can also be used in other forms of grid model.
Ključne besede: triangular mesh, model, lossless, compression
Objavljeno: 12.07.2017; Ogledov: 136; Prenosov: 5
Celotno besedilo (332,44 KB)
Dynamic arc fitting path follower for skid-steered mobile robotsPeter Lepej
, Johannes Maurer
, Suzana Uran
, Gerald Steinbauer
, 2015, izvirni znanstveni članek
Opis: Many applications, such as surveillance, inspection or search and rescue operations, can be performed with autonomous robots. Our aim is a control of modular autonomous systems in rescue robotics. One of the basic problems with autonomous robotics is the execution part where the control commands (translation and rotational velocities) are produced for mobile bases. Therefore we have focused on this area because there is only a small amount of available path following software for skid-steered mobile robots. Our goal was to develop a velocity controller that could be used for multiple skid-steered mobile bases. We considered differential drive mobile bases such as tracked skid-steering mobile bases. Our approach is based on an arc fitting algorithm, which takes into account the robot constraints and kinematical model. It produces a continuous trajectory where fitting to the given path is adapted based on given parameters. Moreover, we have included orientation angle compensation while the mobile robot is moving and ground inclination compensation. Our rescue robot is described, together with the simulation setup and algorithm implementation. We compared our algorithm to the Hector-based software and curvature velocity approach. The results for the proposed algorithm are shown for the simulation results and the experiment.
Ključne besede: mobile robot, arc fitting, path following, velocity control, rescue robot
Objavljeno: 12.07.2017; Ogledov: 110; Prenosov: 3
Celotno besedilo (1,43 MB)