Proposal of methods of end of life vehicles processing

Práce vysvětluje definice základních pojmů z oblasti ekologické likvidace autovraků, popisuje strukturu a stáří současného vozového parku, zmiňuje legislativu ekologické likvidace autovraků a způsoby nakládání s autovraky v zemích EU. Dále je v práci uvedeno materiálové složení automobilu a možné způsoby zpracování autovraků. V závěru práce je navrhnuta metoda zpracování autovraků.The work explains definition of basic concepts from ecological liquidation end of life vehicles areas, describes structure and age of present rolling-stock, mentions legislation on ecological liquidation of end of life vehicles and means dispose of end of life vehicles in EU countries. Next it is in work mentioned the material composition of vehicle and possible modes of end of life vehicles processing. At the close work it is drafted method of end of life vehicles processing.Katedra dopravních prostředků a diagnostikyDokončená práce s úspěšnou obhajobo

Texture evolution in biocompatible Mg-Y-Re alloy after friction stir processing

The presented study deals with the investigation of biocompatible WE 43 Mg-based alloy processed via the combination of rotary swaging (RS) and friction stir processing (FSP) at three different rotational speeds of 400 RPM, 800 RPM, and 1200 RPM. The structure observations primarily focused on texture development and characterizations of grain sizes and grain boundaries. The results showed that swaging plus processing at 400 RPM and 1200 RPM lead to substantial recrystallization and grain refinement. The fractions of low angle grain boundaries within the 400 RPM and 1200 RPM samples were approximately 11%, while for the 800 RPM sample exhibiting secondary recrystallization it was about 22%. The grains were also the finest in the 1200 RPM sample (average grain diameter of 1.8 mu m). The processed structures exhibited a slight tendency to form the {10-10} preferential fiber texture (especially the 800 RPM sample). Tensile testing showed the FSP to have positive influence on the ultimate tensile stress, as well as ductility of all the samples; the mechanical properties improved with increasing FSP rate.Web of Science911art. no. 118

Efficiency increasing of assembly cell

Tato diplomová práce se zabývá zvýšením efektivity montážního pracoviště (výrobní linky). Postupně pojednává o štíhlé výrobě, jejich základních metodách a emisní normě EURO VI, která úzce souvisí s produkovaným výrobkem. V hlavní části je poté proveden rozbor současného stavu za pomoci výše uvedených metod a návrh řešení pro zajištění kýžené efektivity. Na základně těchto poznatků je následně navržena automatizace testovací stanice, a to včetně 3D modelu, výkresové dokumentace, etap realizace i reálné cenové kalkulace se závěrečným posouzením efektivity, návratnosti i analýzy rizik. Druhá zpracovaná doplňující varianta se posléze zabývá úpravou ergonomie výrobní linky a obsahuje 3D model nově navržených stolů, reálnou kalkulaci i závěrečné ekonomické zhodnocení.This diploma thesis deals with increasing the efficiency of the assembly workplace (production line). Thesis gradually discusses with lean production, their basic methods and the EURO VI emission standard, which is closely related to the produced product. In the main part, an analysis of the current state is performed with the help of the above-mentioned methods and a proposal of solutions to ensure efficiency. On the base of these findings, the automation of the test station is proposed, including a 3D model, drawing documentation, phases of implementation and real cost calculations with a final assessment of efficiency, return of investments and risk analysis. The second elaborated complementary variant deals with the ergonomics of the production line and includes a 3D model of newly designed tables, real calculations and final economic evaluation.

Dynamic Changes in the Terrain

Tato práce se zabývá návrhem, realizací a analýzou modelu pro dynamickou deformaci terénu. Je popsán současný stav problematiky dynamických změn terénu v prostředí OpenSceneGraph a je uveden dostupný relevantní software TDS, který umožňuje adaptovat terén podle nově přidaných objektů. Zvláštní důraz je kladen na návrh modelu pro fyzikální deformace terénu, které jsou způsobeny pohybujícím se tělesem nebo explozí výbušniny. Výsledky simulačních testů jsou prezentovány a na základě analýzy modelu jsou navrženy a realizovány optimalizace, které mnohonásobně zefektivňují výsledný algoritmus.This thesis deals with design, implementation and analysis of the model for dynamic changes in the terrain. Present state of terrain deformation in OpenSceneGraph environment is described and available relevant software called TDS, which allows terrain adaptation to new inserted objects is presented. Special emphasis is placed on design of model for physically based terrain deformations that are caused by moving object or by bomb explosion. The results of simulation tests are presented and on the base of model analysis, the optimizations, which significantly improve final algorithm, are designed and realized.

Programming of KUKA industrial robots

Tato bakalářská práce pojednává o analýze aktuálních možností programování průmyslových robotů. Postupně se zabývá průmyslovými roboty používanými k manipulaci, jednotlivými druhy programování, jejich vlastnostmi, porovnáním a seznamuje s novými trendy v oblasti on-line, off-line a CAD/CAM programování. V závěrečné části této práce je řešena demonstrační aplikace pomocí podtlakové úchopné hlavice, jejímž výsledkem je obecný algoritmus a manipulační program pro robot KUKA.This bachelor’s thesis discusses with analysis of current options of industrial robots programming. It deals with manipulating industrial robots, their different programming types, properties, comparison and introduces with new trends in the field of on-line, off-line and CAD/CAM programming. Demonstration gripping task with vacuum gripper, whose resulting in a general algorithm and manipulation program for KUKA robot, is solved in final part of this thesis.

NUMERICAL MODELLING OF WAVE SHAPES DURING SHPB MEASUREMENT

The paper aims at the numerical simulation of the wave propagation in compressive Split Hopkinson Pressure Bar (SHPB) experiment. The paper deals with principles of SHPB measurement, optimisation of a numerical model and techniques of pulse shaping. The parametric model of the typical SHPB configuration developed for LS-DYNA environment is introduced and optimised (in terms of element size and distribution) using the sensitivity study. Then, a parametric analysis of a geometric properties of the pulse shaper is carried out to reveal their influence on a shape of the incident pulse. The analysis is algorithmized including the pre- and post-processing routines to enable automated processing of numerical results and comparison with the experimental data. Results of the parametric analysis and the influence of geometric properties of the pulse shaper (diameter, length) on the incident wave are demonstrated

Asynchronous time integration while achieving zero interface energy

This contribution deals with an asynchronous direct time integration of the finite-element model. The proposed method is applied to the phenomenon of wave propagation through an elastic linear continuum. The numerical model is partitioned into individual subdomains using the domain decomposition method by means of localized Lagrange multipliers. For each subdomain, different time discretizations are used. No restrictions for relation between subdomain’s time steps are imposed. The coupling of the subdomains is forced by an acceleration continuity condition. Additionally, we use the a posteriori technique to also provide the displacement and velocity continuity at the interfaces, and hence we obtain exact continuity of all three kinematic fields. The proposed method is experimentally validated using the modified SHPB (split Hopkinson pressure bar) setup

Double Bark Thickness Estimation Models of Common European Broadleaved Species for Harvester Timber Volume Estimation in Czechia

The share of the annual volume of harvester-produced timber in Czech forest bioeconomy has increased in the last decades. To estimate under-bark timber volume, harvester systems allow choosing between two different bark deduction models – diameter band (DBM) and linear model. However, linear models were not calibrated for the conditions of Czech forestry. Therefore, the objective of this research was to develop, for local conditions in Czechia, linear functions for estimating the double bark thickness of two groups of broadleaved species (beech and oak) and to test their viability based on real harvest data. To create the linear functions, official Czech cubing tables were used. Data from real harvests were gathered from fifteen harvesters. A sample containing 4995 logs belonging to the beech group was analyzed using descriptive statistics and the Paired Wilcoxon tests. The mean double bark thickness for beech group was 15.1 mm (polynomial and linear model). For oak group, it was 15.48 mm (polynomial) or 15.49 mm (linear). The results of real harvests for beech group revealed that the mean double bark thickness estimated by the polynomial function was 7.08 mm. The linear function estimates were closer to the value estimated by the polynomial (6.84 mm) than DBM estimates (6.68 mm). Therefore, we can state that the newly developed linear models can be used in fully mechanized harvesting instead of manual bark deduction methods in Czechia