Tribological properties of Al2O3 layers after thermo-chemical treatment

The article presents the influence of the thermo-chemical treatment of Al2O3 layers on their tribological properties. The Al2O3 layers were produced on the EN AW-5251 aluminium alloy by means of direct current anodizing in a three-component electrolyte. For the sake of comparison, some of the samples were thermochemically treated in three liquids (sodium sulphate solution, sodium dichromate solution, distilled water). The parameters of the production and thermo-chemical treatment were selected on the basis of two Hartley's plans. The tribological properties were determined on the basis of a tribological test carried out for a pin-on-disc friction pair on a T-17 tester in reciprocating motion. The tests were carried out in conditions of technically dry friction. Thanks to the tests, coefficient of friction µ and the mass wear, together with the intensity of the material wear were determined. The use of thermo-chemical treatment in the sodium dichromate solution contributed to an increase in coefficient of friction μ and a reduction in the wear intensity of the polymer from 36 μg/km (layer without thermo-chemical treatment) to 21.33 μg/km (layer after thermo-chemical treatment in the sodium dichromate solution).The conducted stereometric tests before and after the tribological test for selected samples allow the authors to state that the thermo-chemical treatment in the sodium dichromate solution increases the amplitude parameters of surface roughness. The study of the surface morphology of the layer with the lowest mass wear showed the formation of an additional sub-layer as a result of thermo-chemical treatment carried out in the sodium dichromate solution

Modelovanie mechanizmu s paralelnou kinematickou štruktúrou v softvéri Matlab/Simulink

The article deals with the preparation of simulation model of mechanism with parallel kinematic structure called hexapod as an electro-mechanical system in software MATLAB/Simulink. The simulation model is composed from functional blocks represented each part of mechanism’s kinematic structure with certain properties. The results should be used for further simulation of its behaviour as well as for generating of control algorithms for real functional prototype.Článok sa zaoberá modelovaním mechanizmu s paralelnou kinematickou štruktúrou nazývaného hexapod ako elektromechanického systému v prostredí softvéru MATLAB/Simulink. Simulačný model je zložený z funkčných blokov, ktoré predstavujú jednotlivé časti kinematickej štruktúry mechanizmu s určitými vlastnosťami. Výsledky môžu byť použité pre budúcu simuláciu jeho správanie, ako aj pre generovanie riadiacich algoritmov pre reálny funkčný prototyp

Methods of pre-identification of TITO systems

The content of this article is the presentation of methods used to identify systems before actual control, namely decentralized control of systems with Two Inputs, Two Outputs (TITO) and with two interactions. First, theoretical assumptions and reasons for using these methods are given. Subsequently, two methods for systems identification are described. At the end of this article, these specific methods are presented as the pre-identification of the chosen example. The Introduction part of the paper deals with the description of decentralized control, adaptive control, decentralized control in robotics and problem formulation (fixing the identification time at the existing decentralized self-tuning controller at the beginning of control and at the beginning of any set-point change) with the goal of a new method of identification. The Materials and methods section describes the used decentralized control method, recursive identification using approximation polynomials and least-squares with directional forgetting, recursive instrumental variable, self-tuning controller and suboptimal quadratic tracking controller, so all methods described in the section are those ones that already exist. Another section, named Assumptions, newly formulates the necessary background information, such as decentralized controllability and the system model, for the new identification method formulated in Pre-identification section. This section is followed by a section showing the results obtained by simulations and in real-time on a Coupled Drives model in the laboratory. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.European Regional Development Fund under the project CEBIA-Tech [CZ.1.05/2.1.00/03.0089]; Ministry of Education, Science, research and Sport of the Slovak Republic [1247/2018]Ministerstvo školstva, vedy, výskumu a športu Slovenskej republiky; European Regional Development Fund, ERDF: CZ.1.05/2.1.00/03.008

VISION GUIDED PARALLEL ROBOT AND ITS APPLICATION FOR AUTOMATED ASSEMBLY TASK

The article deals with the application of vision guided parallel robot FANUC M-1iA for automated assembly process. Vision system is used for object identification and filtering the data about its position and orientation. Control system based on iR Vision system can process data collected from camera Sony XC-56 fixed to the frame and navigate the end-effector to grasp and move selected objects. Integration of vision guided robot control into the high speed parallel robot can reach high productivity. The functionality of vision guided robot system is demonstrated at automated assembly process of USB memory stick with variable positioning of its components

Conceptual Design and Simulation of Cable-driven Parallel Robot for Inspection and Monitoring Tasks

The paper deals with the conceptual design of cable-driven parallel robot which will be used for inspection and monitoring tasks in production process. The reason and need of vision based control of the production process is described in the introduction. Furthermore, mechanisms with parallel kinematic structure are described, as well as their usage in industry and sports broadcasts. On that basis, there is proposed the conceptual design of the cable driven parallel robot (CDPR) for desired task of visual monitoring of production line. Finally, there is proposed a simulation of designed robotic system and workspace shape analysis

The space distribution and transfer of positioning errors from actuators to the TCP point of parallel mechanism

The article deals with the analysis of the transfer and distribution of inaccuracies from actuators to the position of the point TCP on one of these machines. The real functional model of the mechanism was developed at the authors’ workplace. The analyses of the workspace were carried out on CAD model. The results should be used for simulation of mechanism’s behaviour, structural optimization as well as for generating of control algorithms for real functional prototype

The mould for production of plastic spout cap with internal thread by injection moulding

The main aim of this article is the mould design for production of plastic spout cap with inner thread by injection moulding technology. There are described the basic steps of whole design process with respect to fulfil all technology and functionality requirements. The application of hot runner system as well as hybrid ejection system based on rotary cores and stripper plate can be considered as the main innovative features of the designed mould. The mould flow analysis was carried out for the functionality demonstration

The space distribution and transfer of positioning errors from actuators to the TCP point of parallel mechanism

The article deals with the analysis of the transfer and distribution of inaccuracies from actuators to the position of the point TCP on one of these machines. The real functional model of the mechanism was developed at the authors’ workplace. The analyses of the workspace were carried out on CAD model. The results should be used for simulation of mechanism’s behaviour, structural optimization as well as for generating of control algorithms for real functional prototype

Analysis of Laser Sensors and Camera Vision in the Shoe Position Inspection System

Inspection systems are currently an evolving field in the industry. The main goal is to provide a picture of the quality of intermediates and products in the production process. The most widespread sensory system is camera equipment. This article describes the implementation of camera devices for checking the location of the upper on the shoe last. The next part of the article deals with the analysis of the application of laser sensors in this task. The results point to the clear advantages of laser sensors in the inspection task of placing the uppers on the shoe’s last. The proposed method defined the resolution of laser scanners according to the type of scanned surface, where the resolution of point cloud ranged from 0.16 to 0.5 mm per point based on equations representing specific points approximated to polynomial regression in specific places, which are defined in this article. Next, two inspection systems were described, where one included further development in the field of automation and Industry 4.0 and with a high perspective of development into the future. The main aim of this work is to conduct analyses of sensory systems for inspection systems and their possibilities for further work mainly based on the resolution and quality of obtained data. For instance, dependency on scanning complex surfaces and the achieved resolution of scanned surfaces

Delta robots – robots for high speed manipulation

Ovaj je rad usmjeren definiranju paralelnih kinematičkih robota, opisu njihove specifične primjene, usporedbi robota raznih proizvođača i određivanju parametara brzine i ubrzanja, kinematičkoj analizi – inverznoj i unaprijednoj kinematici. Obaviještava o razvoju Delta robota na Akademiji, uključujući i Sveučilište u Žilini, te o Delta robotima na tržištu. Dva su modela Delta robota, M-1iA i M-3iA razvijena u FANUC Robotics zadnjih nekoliko godina. Ti su roboti idealni za automatiziranje poslova koji su bili previše brzi i složeni za standardne robote. Uz to, ova nova serija robota nudi fleksibilnost pokreta ljudskog zgloba, brzo vrijeme ciklusa, krajnje kompaktnu ruku i visoku preciznost. Također je moguća podrška inteligentnim funkcijama korištenjem Computer Vision sustava. U radu se opisuje razvoj mjesta za obuku s Fanuc Delta robotima FANUC M-1iA 0.5A, uz primjere o primjeni robota.This paper is oriented to parallel kinematic robots definition, description of their specific application, comparison of robots made by different producers and determination of velocity and acceleration parameters, kinematic analysis – inverse and forward kinematic. It brings information about development of Delta robots at Academia, including the University of Žilina and Delta robots in the market. Two models of Delta robots called M-1iA and M-3iA have been developed by FANUC Robotics during the last several years. These robots are ideal to automate tasks which so far were too fast and too complex for standard robots. In addition, this new family of robot series offers the motion flexibility of a human wrist, fast cycle times, ultra compact arm and high precision. It is also possible to support intelligent functions using Computer Vision System. In this paper is described the development of training workplace with Fanuc Delta robot FANUC M-1iA 0.5A with examples of robot application