Ziga Gosar

The dataset contains anonymous and aggregated data related to the surveys for the initial assessment of application performance originated in the framework of REMODEL project, and presented in the deliverable "D2.3 – Initial assessments of application performance".

The handling of flexible materials is complicated task in robotics and automation. Due to deformability and fragility of flexible materials, robots are equipped with the state-of-the-art sensors and grippers to perform such tasks. Nonetheless, industry still lacks for approaches and techniques for handling these materials. Therefore, several industries and mass production systems require hiring human to perform the deformable materials-related task. These tasks might include usage of toxic martials (e.g. carbon fiber sheets) or dangerous tools (e.g. sharp cutting knives). In this regard, this paper presents an approach for selecting grasping configuration of objects based on the product’s properties such as rigidity, surface roughness and shape, and the required task. Briefly, this research is based on several published taxonomies for modeling the hand of the human while grasping different objects. After refining the taxonomy, an ontology model is populated which will be queried for...

In order to survive in today’s highly competitive global market, small and medium-sized enterprises (SMEs) have had to transition from sequential to concurrent product development, which significantly shortens development cycles, reduces costs, and ensures high product quality. Despite its many benefits, concurrent product development is still based on detailed upfront planning and cannot address the challenges related to today’s ever-growing uncertainty, constantly changing environment, and unstable requirements. A potential solution to this problem could be in more flexible and value-driven agile project management (APM) approaches, typical of software development. In this paper, we propose a new product development model specifically appropriate for SMEs that combines concurrent product development principles with APM elements. It is designed as a loop of five repetitive steps (macroplan, microplan, iteration activities, review, and retrospective) that are being executed within i...

In today’s highly dynamic and unpredictable project environment, companies need to be able to manage changes quickly and effectively, otherwise, the final product will not be current and will only go to waste. Traditional project management approaches that focus on planning are no longer efficient and companies are forced to adopt new ways of working. As a result, more flexible agile project management (APM) approaches have emerged over the last decades. Originally developed for the software industry, APM is now increasingly recognized and adopted also by other industry sectors. However, due to some discipline-specific differences, the adoption of APM by non-software companies is challenging and requires many adjustments and high financial input. While the larger organizations have sufficient resources to make such a transition, small and medium-sized enterprises (SMEs) generally cannot afford to do so, and therefore need alternative strategies to increase their agility and stay com...

An extremely asymmetric low-pressure discharge was used to study the composition of thin films prepared by PECVD using HMDSO as a precursor. The metallic chamber was grounded, while the powered electrode was connected to an RF generator. The ratio between the surface area of the powered and grounded electrode was about 0.03. Plasma and thin films were characterised by optical spectroscopy and XPS depth profiling, respectively. Dense luminous plasma expanded about 1 cm from the powered electrode while a visually uniform diffusing plasma of low luminosity occupied the entire volume of the discharge chamber. Experiments were performed at HMDSO partial pressure of 10 Pa and various oxygen partial pressures. At low discharge power and small oxygen concentration, a rather uniform film was deposited at different treatment times up to a minute. In these conditions, the film composition depended on both parameters. At high powers and oxygen partial pressures, the films exhibited rather unusu...

The research results of signal recognition using neural networks are presented. A multilayer perceptron with back-propagation error is implemented on Java. The optimal number of neurons in the hidden layer is selected for building an effective architecture of the neural network. Training network on different sets of signals with noise allowed teaching her to work with distorted information, which is typical for non-destructive testing in real conditions. Experiments were performed to analyze MSE values and accuracy.

An industrial size plasma reactor of 5 m3 volume was used to study the deposition of silica-like coatings by the plasma-enhanced chemical vapor deposition (PECVD) method. The plasma was sustained by an asymmetrical capacitively coupled radio-frequency discharge at a frequency of 40 kHz and power up to 7 kW. Hexamethyldisilioxane (HMDSO) was introduced continuously at different flows of up to 200 sccm upon pumping with a combination of roots and rotary pumps at an effective pumping speed between 25 and 70 L/s to enable suitable gas residence time in the plasma reactor. The deposition rate and ion density were measured continuously during the plasma process. Both parameters were almost perfectly constant with time, and the deposition rate increased linearly in the range of HMDSO flows from 25 to 160 sccm. The plasma density was of the order of 1014 m−3, indicating an extremely low ionization fraction which decreased with increasing flow from approximately 2 × 10−7 to 6 × 10−8. The cor...

Optical emission spectroscopy and mass spectrometry was used to characterize gaseous plasma in an industrial reactor of volume 5 m3 during deposition of protective coatings. Plasma was created in mixtures of hexamethyldisiloxane (HMDSO) and oxygen at the powers between 1 and 8 kW. The plasma density was somehow below 1014 m−3. The flows of both gases were varied up to 200 sccm while the effective pumping speed was adjusted by changing the roots pump rotation speed between 250 and 4000 rpm. At such conditions the HMDSO was only partially dissociated to fragments. The behaviour of optical emission lines and mass ion currents was well correlated indicating that even one single technique was sufficient to monitor the behaviour of plasma at various discharge conditions. The optical emission spectroscopy as a simple and economic method is therefore suitable for controlling key processing parameters in such a plasma reactor.

The deposition of protective coatings on aluminised polymer substrates by a plasma enhanced chemical vapour deposition PECVD technique in a plasma reactor with a volume of 5 m3 was studied. HMDSO was used as a precursor. Plasma was sustained in a capacitively coupled radiofrequency (RF) discharge powered by an RF generator operating at 40 kHz and having an adjustable output power up to 8 kW. Gaseous plasma was characterised by residual gas mass spectrometry and optical emission spectroscopy. Polymer samples with an average roughness of approximately 5 nm were mounted into the plasma reactor and subjected to a protocol for activation, metallisation and deposition of the protective coating. After depositing the protective coating, the samples were characterised by secondary ion mass spectrometry (SIMS) and X-ray photoelectron spectroscopy (XPS). The combination of various techniques for plasma and coating characterisation provided insight into the complex gas-phase and surface reactio...

Cellulose is a promising biomass material suitable for high volume applications. Its potential lies in sustainability, which is becoming one of the leading trends in industry. However, there are certain drawbacks of cellulose materials which limit their use, especially their high wettability and low barrier properties, which can be overcome by applying thin coatings. Plasma technologies present a high potential for deposition of thin environmentally friendly and recyclable coatings. In this paper, two different plasma reactors were used for coating two types of cellulose-based substrates with hexamethyldisiloxane (HMDSO). The changes in surface characteristics were measured by atomic force microscopy (AFM), scanning electron microscopy (SEM), surface free energy and contact angles measurements, X-ray photoelectron spectroscopy (XPS), and secondary ion mass spectrometry (SIMS). Successful oleofobization was observed for an industrial scale reactor where pure HMDSO was used in the abs...

Cellulose is a promising biomass material suitable for high volume applications. Its potential lies in sustainability, which is becoming one of the leading trends in industry. However, there are certain drawbacks of cellulose materials which limit their use, especially their high wettability and low barrier properties, which can be overcome by applying thin coatings. Plasma technologies present a high potential for deposition of thin environmentally friendly and recyclable coatings. In this paper, two different plasma reactors were used for coating two types of cellulose-based substrates with hexamethyldisiloxane (HMDSO). The changes in surface characteristics were measured by atomic force microscopy (AFM), scanning electron microscopy (SEM), surface free energy and contact angles measurements, X-ray photoelectron spectroscopy (XPS), and secondary ion mass spectrometry (SIMS). Successful oleofobization was observed for an industrial scale reactor where pure HMDSO was used in the absence of oxygen.

An extremely asymmetric low-pressure discharge was used to study the composition of thin films prepared by PECVD using HMDSO as a precursor. The metallic chamber was grounded, while the powered electrode was connected to an RF generator. The ratio between the surface area of the powered and grounded electrode was about 0.03. Plasma and thin films were characterised by optical spectroscopy and XPS depth profiling, respectively. Dense luminous plasma expanded about 1 cm from the powered electrode while a visually uniform diusing plasma of low luminosity occupied the entire volume of the discharge chamber. Experiments were performed at HMDSO partial pressure of 10 Pa and various oxygen partial pressures. At low discharge power and small oxygen concentration, a rather uniform film was deposited at dierent treatment times up to a minute. In these conditions, the film composition depended on both parameters. At high powers and oxygen partial pressures, the films exhibited rather unusual behaviour since the depletion of carbon was observed at prolonged deposition times. The results were explained by spontaneous changing of plasma parameters, which was in turn explained by the formation of dust in the gas phase and corresponding interaction of plasma radicals with dust particles.

An industrial size plasma reactor of 5 m^3 volume was used to study the deposition of silica-like coatings by the plasma-enhanced chemical  vapor deposition (PECVD) method. The plasma was sustained by an asymmetrical capacitively coupled radio-frequency discharge at a frequency of 40 kHz and power up to 7 kW. Hexamethyldisilioxane (HMDSO) was introduced continuously at different flows of up to 200 sccm upon pumping with a combination of roots and rotary pumps at an effective pumping speed between 25 and 70 L/s to enable suitable gas residence time in the plasma reactor. The deposition rate and ion density were measured continuously during the plasma process. Both parameters were almost perfectly constant with time, and the deposition rate increased linearly in the range of HMDSO flows from 25 to 160 sccm. The plasma density was of the order of 10^14 m^(−3) , indicating an extremely low ionization fraction which decreased with increasing flow from approximately 2 × 10^(−7) to 6 × 10^(−8). The correlations between the processing parameters and the properties of deposited films are drawn and discussed.

Optical emission spectroscopy and mass spectrometry was used to characterize gaseous plasma in an industrial reactor of volume 5 m^3 during deposition of protective coatings. Plasma was created in mixtures of hexamethyldisiloxane (HMDSO) and oxygen at the powers between 1 and 8 kW. The plasma density was somehow below 10^14 m^(−3). The flows of both gases were varied up to 200 sccm while the effective pumping speed was adjusted by changing the roots pump rotation speed between 250 and 4000 rpm. At such conditions the HMDSO was only partially dissociated to fragments. The behaviour of optical emission lines and mass ion currents was well correlated indicating that even one single technique was sufficient to monitor the behaviour of plasma at various discharge conditions. The optical emission spectroscopy as a simple and economic method is therefore suitable for controlling key processing parameters in such a plasma reactor.

The provision of a particle and power exhaust solution which is compatible with first-wall components and edge-plasma conditions is a key area of present-day fusion research and mandatory for a successful operation of ITER and DEMO. The work package plasma-facing components (WP PFC) within the European fusion programme complements with laboratory experiments, i.e. in linear plasma devices, electron and ion beam loading facilities, the studies performed in toroidally confined magnetic devices, such as JET, ASDEX Upgrade, WEST etc. The connection of both groups is done via common physics and engineering studies, including the qualification and specification of plasma-facing components, and by modelling codes that simulate edge-plasma conditions and the plasma–material interaction as well as the study of fundamental processes. WP PFC addresses these critical points in order to ensure reliable and efficient use of conventional, solid PFCs in ITER (Be and W) and DEMO (W and steel) lifetime estimates (erosion, material mixing and surface morphology), and safety aspects (fuel retention, fuel removal, material migration and dust formation) particularly for quasi-steadystate conditions. Alternative scenarios and concepts (liquid Sn or Li as PFCs) for DEMO are developed and tested in the event that the conventional solution turns out to not be functional. Here, we present an overview of the activities with an emphasis on a few key results: (i) the observed synergistic effects in particle and heat loading of ITER-grade W with the available set of exposition devices on material properties such as roughness, ductility and microstructure; (ii) the progress in understanding of fuel retention, diffusion and outgassing in different W-based materials, including the impact of damage and impurities like N; and (iii), the preferential sputtering of Fe in EUROFER steel providing an in situ W surface and a potential first-wall solution for DEMO.

This work experimentally and numerically studies large deflection of slender cantilever beam of linear elastic material, subjected to a combined loading which consists of internal vertical uniformly distributed continuous load and external vertical concentrated load and a horizontal concentrated load at the free end of the beam. We got equations with the help of large deflection theory, and present the differential equation governing the behaviour of this system and show that that this equation, although straightforward in appearance, is in fact rather difficult to solve due to the presence of a non-linear term. A numerical evaluation is used to evaluate the system and calculate Young`s modulus of the beam material. With simple experiment we show, how a Young`s modulus can be obtained and then the phenomenon of the large elastic sideways deflection of a column under compressive loading is investigated and elastica of buckled column is calculated.

Bimetallic shallow shells are thermal sensors. The paper presents relevant technical information on bimetallic shallow shells and describes some interesting physical experiments. It is shown how, through simple measurements and calculations, it is possible to determine the initial speed (~3.5 m/s), the acceleration (~30000 m/s²) and the lower and upper snap temperature (~22 °C; ~32 °C) of the bimetal. The results from calculations are comparable to those obtained by a high speed camera. The videos give an even deeper insight into the phenomenon of the snap-through.

The purpose of the work is to determine the mechanical and thermal properties of composite polymeric materials. The group of samples consisting of a sample of polypropylene, three samples of polypropylene with quartz sand of different granulations and a sample of polypropylene with calcium carbonate. Shares of impurities in base material were identical. The dependence and durability of the material was determined by measuring shear strength, structural analysis of the material (degree of crystallinity) and measurements of differential scanning calorimetry (DSC analysis). The result of a DSC experiment is a curve of heat flux versus temperature or versus time. There are two different conventions: exothermic reactions in the sample shown with a positive or negative peak, depending on the kind of technology used in the experiment. The results show that the added inorganic particles to the primary polymer material change the initial kinetics of the formation process of the structure. This consequently leads to changes in the behavior of the final product. It should be particularly noted that all additives affect the reduction of the compliancy of the shear creep as a function of temperature. Additives similarly affect the dependence of the compliancy of the shear creep as a function of time.

The quality of the polymer product is defined by its functionality and durability. Functionality and durability of this system depend on the structure of the material in the product. Changes in the structure of materials at the macro scale will cause a change of material characteristics, which are taken as an advantage of polymers in solving a given problem. Material properties of a given polymer material depend on the boundary conditions that result in modification of the structure. Research work presents how temperature influences on change of material properties in such a way that the material due to the impact absorbs more energy. Such a material could be used to protect a variety of objects due to the impact. The objective is to present the dependence of the damping properties of the product in the impulse loading in dependence on the temperature and the material. Determination of physical characteristics, which we have identified, can be dissipated at a certain temperature. In the experiment, we confirm the assertion that it is possible to change the damping properties of the polymeric material with temperature. It was confirmed that rapid increase in impact resistance corresponds to transition from brittle to ductile type of failure.

Povzetek. V delu je obravnavan preskok sistema dvakrat povezane plitke rotacijsko ne osnosimetrične dvoslojne lupine v homogenem temperaturnem polju. Obravnava problema zahteva obravnavo ravnovesje sil in momentov na deformiranem sistemu ob sočasnem upoštevanju teorije velikih premikov. Na osnovi izbrane nelinearne teorije je bil izdelal fizikalno matematični model, s katerim je popisana geometrija sistema, premično in napetostno termo-mehansko stanje. Model lupine je izdelan z metodo končnih elementov (MKE). Dvoslojna plitka lupina mora v svoji življenjski dobi zdržati 10^7 preklopov. Zaradi velikega števila preskokov sistema morajo biti lupine dimenzionirane na trajno dinamično trdnost. Predstavljeni so rezultati napetosti, ki se pojavijo v času preskoka sistema plitke lupine. Napetosti, ki se pojavijo v geometrijskih stanjih lupine so v elastičnem območju in ne presegajo 85% maksimalne elastične vrednosti napetosti.

In this work were made out absolute measurements of the electron density in the ECR discharge plasma at moderate pressures by optical emission spectroscopy (OES). The range of plasma parameters suitable for nanostructuring, functionalization and optimal wettability of polymer material in a reasonable treatment time was evaluated. The flux of positively charged oxygen ions was varied between discharge parameters. The flux of neutral atoms was varied independently from discharge parameters (and thus the ion flux) using a movable recombinator. The corresponding fluences was achieved by variation of treatment time. Plasma parameters were measured by electrical and catalytic probes, optical spectroscopy and mass spectrometry, while surface finish by atomic force and scanning electron microscopies. The optimal range of plasma parameters was determined in a big industrial reactor of volume 6000 liters. The coupling of discharges suitable for achieving the optimal range of plasma parameters as determined with high performance computer was studied for large reactors first theoretically and then experimentally using alternative electrode configurations. Once optimal plasma parameters were achieved in the large size reactor the production of components for automotive industry went on. Variations in the discharge parameters and the electron temperature of HMDSO plasma have been investigated in the pressure range of 1 × 10-2 to 7 × 10-2 mbar at MF plasma of power up to 9 kW. The plasma electron temperature in the above ranges of gas pressures and input powers has been measured and determined using optical emission spectroscopy (OES) from the intensity ratios of spectral lines. The OES results agree qualitatively and quantitatively with the data obtained using the double probe. The results of the research activity were optimized production parameters of process in automotive industry.

Small and medium size enterprises (SMEs) often have small batch production. It leads to decreasing product lifetimes and also to more frequent product launches. In order to assist such production, a highly reconfigurable robot workcell is being developed. In this work, a visual inspection system designed for the robot workcell is presented and discussed in the context of the automotive light assembly example. The proposed framework is implemented using ROS and OpenCV libraries. We describe the hardware and software components of the framework and explain the system's benefits when compared to other commercial packages.

Za uporabo robotov v maloserijski proizvodnji je potrebno obiti številne težave. Menjava serije izdelkov je drag časovno zamuden proces zato se robotska proizvodnja običajno uporablja v velikoserijski proizvodnji. Da bi omejitev obšli je bila v sklopu projekta ReconCell razvita robotska celica naslednje generacije, ki s pomočjo fleksibilnih in rekonfigurabilnih pristopov obvladuje proizvodnjo raznolikih izdelkov. V članku so opisani ključni mehanski in programski pristopi, ki to omogočajo. Obravnavana je tudi njihova implementacija ter rezultati njihove uporabe na področju proizvodnje avtomobilskih žarometov.

The paper deals with the buckling and mechanical conditions in the thin shallow double layered shell with star shape opening on top of the shell. According to the theory of third order, which takes into account the equilibrium state of forces and moments which are acting on the deformed system, the thesis is presenting a model with mathematical description of the geometry of the system, stresses, thermo elastic strains and displacements. As an example, the results of spherical shallow shells are analysed with finite element method. Besides simply-roller supported shells, also simply bearing-supported and clamped shells are discussed. The shells are loaded with temperature and/or with concentrated acting load at the top of it.

ReconCell aims at designing and implementing a new kind of an autonomous robot workcell, which will be attractive not only for large production lines but also for few-of-a-kind production, which often takes place in SMEs. The proposed workcell is based on novel ICT technologies for programming, monitoring and executing assembly operations in an autonomous way. It can be nearly automatically reconfigured to execute new assembly tasks efficiently, precisely, and economically with a minimum amount of human intervention. This approach is backed up by a rigorous business-case analysis, which shows that the ReconCell system is economically viable also for SMEs.

Robotizirana strega polizdelkov je v avtomobilski industriji že dobro uveljavljena. Ta je pogosto povezana z vizualno kontrolo. Tako je potrebno usklajeno delovanje vizualne kontrole in obvladovanja gibanja v majhnem delovnem območju z upoštevanjem kratkih časov ciklov izdelave za obe fazi procesa. Hitro lahko ugotovimo, da človek vsem omenjenim zahtevam težko zadosti, če pa upoštevamo še v industriji zelo zaželeno čim večjo ponovljivost v daljšem časovnem obdobju, vidimo, da res dober končni rezultat lahko dosežemo le z robotizacijo in strojnim vidom. Strojni vid in industrijski roboti zaradi svoje ponovljivosti, hitrosti, gibljivosti in fleksibilnosti predstavljajo eno izmed ustreznih rešitev Podjetje ELVEZ se je v ta namen povezalo z inštituti znanja. Skupaj smo na mednarodnem projektu COMET razvili metodo za zmanjšanje stroška izmeta na kosih, ki se metalizirajo. Cilj projekta COMET je postavitev robotske celice za pregled kosov in detekcijo napak na kosih v industrijskem okolju. Z robotsko celico in strojnim vidom preverjamo kakovost kosov po dekorativnih normah. Za zmanjšanje stroškov izmeta in hitrejši odzivni čas v primeru napake pregledujemo surove kose, ki še niso metalizirani. Z ustrezno vizualno metodo detektiramo in vrednotimo vizualne efekte, ki se pojavijo na površini zaradi odboja svetlobe. Demonstracijska robotska celica je postavljena v Leobnu. Cilj za prihodnost je postavitev robotizirane celice s strojnim vidom v industrijsko okolje, kjer se bo ločevalo dobre kose od slabih.

Odsek za avtomatiko, biokibernetiko in robotiko IZVLEČEK V delu, ki je povzetek diplomske naloge, ki je raziskovalne narave, je predstavljena robotizacija delovnega mesta pri kosih, ki imajo visoke dekorativne standarde. V avtomobilski industriji so roboti zelo razširjeni, njihove lastnosti so vse boljše in primerni so za vse bolj zahtevna dela. Namen dela je prikazati, da z robotom v proizvodnji lahko uspešno racionaliziramo najrazličnejše procese, še posebno, če uporabljamo simulacijske postopke. V ta namen je bila v okviru razvojne naloge s programom RobotStudio izdelana simulacija robotizacije delovnega mesta. Posebna pozornost je bila namenjena konstruiranju univerzalnih prstov robotske prijemalke. Z njimi smo omogočili prijemanje levih in desnih kosov, ne da bi pri tem zamenjali prijemalo. Za izvedbo eksperimenta je bil uporabljen ABB robot IRB140. Po izvedbi eksperimenta je bila izdelana tabela, kjer so vidni rezultati realizacije naložene plošče. Ugotovljeno je bilo, da tako kot delavci potrebujejo ergonomsko pripravljeno delovno mesto, tudi roboti v proizvodnji potrebujejo robotu primerno delovno okolje in opremo.