<p>In the heating, ventilation, air conditioning and refrigeration (HVAC&R) industry, bonding and joining play an important role in the manufacturing and assembly process, which is critical to the cost, safety, reliability, and design freedom of systems. The goal of this thesis is to understand and evaluate the usage of adhesive bonds in the manufacture of HVAC&R systems, specifically in regards to leakage/reliability characterization and stress analysis under loading.</p> <p>The bonding performance under static loading is first studied using a commercial epoxy adhesive product. In addition to the traditional surface preparation methods of mechanical and chemical etching, a novel laser-interference surface structuring preparation technique was utilized to improve bonding performance. Laser interference structuring uses a ND:YAG laser beam that is split into two beams that are re-directed to overlap on the same area of a copper alloy. A structuring pattern near the interference structuring limits is achieved due to the phase shift between the beams that is imparted as they are re-directed. Two different laser structuring methods were tested: spot-by-spot and laser raster. Different structuring parameters were varied including the laser spot size and pulses per spot (2, 4, 6, 8, 10, 12 pulses/spot) for the spot-by-spot method, and raster speed (2, 4, 6, 8, 10, 12 mm/s) for laser raster method. The microstructure morphology and surface profile after processing were characterized using the scanning electron microscopy (SEM) and profilometry for all surfaces. It was found that the laser-interference structuring removed the surface contaminants efficiently and formed dot- or net-shaped structures on the surface. This indicates that melting, vaporization, and solidification of the metal happened differently. Due to the much higher speed of the laser raster method, considering practical industrial applications, it is selected for additional investigation for shear strength improvement. The shear strength is measured by a single lap shear test which pulls apart adhesively bonded single lap joint specimen under shear loading using a mechanical tester.</p> <p>Based on the surface profiles, three different laser raster speeds of 2 mm/s, 6 mm/s and 12 mm/s were selected for the manufacture of single lap joint specimens for comparison with the traditional surface preparation methods. The shear lap strength and displacement at maximum load were obtained for the specimens. The laser raster at 6 mm/s increased these values by approximately 11.0% and 25.1%, respectively, while the 12 mm/s condition had an increase of 16.8% and 43.8%, compared with the baseline traditional surface preparation method. It is concluded that laser structuring can enhance the single lap shear joint bonding performance. Within the tested laser processing parameters, a higher laser raster speed results in a larger enhancement. </p> <p>In addition to the static loading test with epoxy adhesive, different adhesive formulations are investigated and developed by the collaborating adhesive manufacturer to determine their suitability for use under the temperature and pressure conditions in HVAC&R systems. Reliability, especially fatigue failure, is another major concern because the strength of the adhesive joints is sufficient for HVAC&R applications. Two primary types of fatigue may happen in practical applications: thermal fatigue and vibration fatigue. Two test facilities were designed and built to test the adhesive performance and understand the failure mechanisms. For the thermal fatigue testing, a novel pressure and temperature cyclic (PTC) test stand was designed to simulate the pressure and temperature changes that may occur in HVAC&R systems. The test stand was designed to switch between hot high-pressure gas and cold low-pressure gas by using a compressor with hot gas bypass setup. For the vibration testing, a standard industrial shaker was used to provide the required vibration at a given displacement and frequency with a specially designed fixture for the tested joints. In both tests, adhesive joints were tested in parallel with brazed joints, undergoing extreme thermal and vibration loading conditions. All the samples were leak-checked before and after the testing, which were found to be leak-free after the testing, indicating that they pass the required qualification test according to available standards. It is confirmed that adhesive joints can be a potential alternative when dealing with thermal and vibration fatigue in the common working conditions of HVAC&R systems.</p> <p>The qualification testing is specific to the required loading conditions, such as pressure and temperature variations, and limited to certain tube sizes. An analytical model is developed to allow for design and evaluation across various operating conditions. The model aims to predict the adhesive stress and strain fields of in tube-to-tube joints based on the geometric parameters, material properties, and the loading conditions. In particular, the model uniquely considers the influence of thermal expansion and contraction in the joint, which is necessary for the periodically changing temperatures in HVAC&R systems. It is numerically solved using Mathematica and validated against the published data in the literature. The exact same solutions are achieved using the reported data in the literature, under simplified conditions without any temperature change involved. The validated model is then used in parametric studies to investigate the influence of geometric sizes and temperature change. Several conclusions are made about the trend of stress changes as well as the maximum stress, which provide insight from a perspective of general design guidance. Adhesive bonding length should be selected such that the maximum stress is smaller than the allowed material strength for both normal and shear stress. Adhesive thickness has less impact in the parametric range considered and is nevertheless usually dictated by the manufacture recommendation in view of other practical considerations. In regard to the thermal stresses, it is found that in practical HVAC&R working environment, the temperature-induced thermal stress dominates the stress fields and leads to significant change in the stress distribution across the adhesive layer. If a temperature change is present, the combination of all possible loading and temperature change should be analyzed to find the most extreme loading condition. This work demonstrates the first stress and strain analysis of tube-to-tube adhesive joints considering the working conditions of HVAC&R applications involving temperature cycling. All of these results provide a detailed guidance for use of adhesive joints across different application or locations in HVAC&R systems. The model can be also used as a framework to evaluate and compare the performance of different adhesives, as long as the adhesive properties are available.</p> <p>Lastly, it is also essential to demonstrate the application of these joints in real HVAC&R systems. A proof-of-concept test was done to demonstrate that the use of adhesive joints in a real system would cause no change in operation or leakage. A commercial heat pump dryer system was used to perform the testing at the Ray W. Herrick Laboratories. Two adhesive joints were installed to replace the brazing joints at the compressor inlet and outlet, where the most extreme temperature and pressure conditions are present. Results show that the system operates without any change in performance and experience no obvious leakage after more than 50 hours of testing over 6 months. </p> <p>This work explores the feasibility and reliability of adhesive bonding of copper for HVAC&R applications. The bonding strength of adhesive was studied and tested with both traditional surface preparation and advanced laser-interference structuring technique. The results show that for the tested structural epoxy adhesive, the bonding strength is large enough considering the internal pressure in the tube and the laser structure technique can increase the shear strength. </p> <p>The long-term reliability with respect to thermal, stress and vibration fatigue are then experimentally investigated and the adhesive joints pass the qualifications tests required by the standard. Further modeling work for predicting the stress distribution in adhesively bonded joints is developed to understand the influence on geometric parameters and temperature change. The adhesive length can influence the stress distribution significantly and temperature-induced stress dominates the stress distribution under the HVAC&R loading conditions. Further material characterization is needed for crack propagation or detailed fatigue analysis, which is highly dependent on the adhesive formula, working environment and loading conditions, which can be performed with a more specific targeted application. The experimental and modeling work in this thesis provides a foundation for adhesives to be applied in HVAC&R applications and a framework to further develop, optimize, and utilize adhesive joining in HVAC&R applications. </p>

Customers are placing ever increasing demands on automotive part manufacturers for high quality parts at low cost. Increasingly, the demand is for zero defects or defect rates in the less than one part per billion. This creates a significant challenge for manufacturers as to how to achieve these low defect levels economically while producing large volumes of parts. Importantly, the presence of infrequent process and measurement (gauge) events can adversely affect product quality. This thesis uses a statistical mixture model that allows one to assume a main production process that occurs most of the time, and secondary rogue events that occur infrequently. Often the rogue events correspond to necessary operator activity, like equipment repairs and tooling replacement. The mixture model predicts that some gauge observations will be influenced by combinations of these rogue events. Certain production applications, like those involving feedback or high-reliability gauging, are heavily influenced by rogue events and combinations of rogue events. A special runtime software profiler was created to collect information about rogue events, and statistical techniques (rogue event analysis) were used to estimate the waste generated by these rogue events. The value of these techniques was successfully demonstrated in three different industrial automotive part production applications. Two of these systems involve an automated feedback application with Computer Numerically Controlled (CNC) machining centers and Coordinate Measuring Machine (CMM) gauges. The third application involves a high-reliability inspection system that used optical, camera-based, machine-vision technology. The original system accepted reject parts at a rate of 98.7 part per million (ppm), despite multiple levels of redundancy. The final system showed no outgoing defects on a 1 million part factory data sample, and a 100 million part simulated data sample. It is expected that the final system reliability will meet the 0.001 ppm specification, which represents a huge improvement. / Doctor of Philosophy (PhD)

The goal of this master’s thesis was design of the inspection procedure for hammer and trigger of the specific revolver model. Thesis was developed in cooperation with the manufacturer of the revolvers. The theoretical part deals with the MSA methodology, which is used to assess acceptability of measurement systems. The practical part describes the current measurement system and performs gage repeatability and reproducibility study. It was confirmed that the current measurement system requires improvement. Subsequently coordinate systems were designed, based on functional features of the hammer and trigger. Automated optical measurements, based on the coordinate systems, were performed. The results from these measurements were again assessed by the gage R&R study. The analysis confirmed improvement of acceptability of the designed measurement systems. Based on these results, it is recommended to apply suggested procedures in practice. Results and recommendations of this master’s thesis can contribute to develop metrology in the company and improve the existing measurement system.

This thesis deals with the analysis of the actuator ACOPOS and its accessories. There are described the cascaded control loop concept and the setting servomechanism from B&R Automation with the important parameters. We follow the draft a speed controller servomotor with a load with the regards to knowledge of the control system. We compare the different methods of labor control actuator at last. There are implemented laboratory tasks of Position servomechanism and speed servo controller-on-load as a demonstration of our achieved results.

The aim of this diploma thesis is the design of robotic table football with the realization of the construction and control a single axis of table football. In introduction are described previously developed solutions. Next chapters contain a selection of specific gaming table and specification of linear, rotary motor. There are presented design visions with the placement of selected component together with proposal location of sensor system for ball detection. In the end of design section is specification and solution of placement safety features. The programming part of the thesis involves the implementation of a communication interface for data processing from the control algorithm of robotic table football.

"S. Dooley: Tertiary Reader" / Approved for public release, distribution is unlimited / This study provides analysis, conclusions and recommendations to assist the Deputy Commandant (DC), Manpower and Reserve Affairs Department (M&RA) and DC, Programs and Resources Department (P&R) in structure and process decisions concerning Marine Corps Manpower budget execution. DC, M&RA is the owner of the Marine Human Resource Development Process (HRDP) and the Military Personnel Marine Corps (MPMC) appropriation sponsor, while the DC, P&R has budgetary (1517) authority for MPMC budget execution. In contrast, the Navy has both sponsorship and 1517 authority within one cell at N1. By comparing these two services' organizational factors and Planning, Programming, Budgeting, and Execution Systems (PPBES), relevant differences surface, conclusions are drawn, and recommendations offered for improvements. Recommendations include realignment of 1517 authority within MPMC execution, and the melding of the Programs and Budget Branch of Manpower Plans Division, M&RA with the Military Personnel Branch, Fiscal Division, P&R (RFM). This new office will be responsible for all facets of MPMC programming, budgeting, and execution. / Captain, United States Marine Corps

L’objectif de ces travaux est de développer une méthode d’aide à la conception des réseaux de chaleur urbains (RCU). Cette méthode utilise un modèle de type MINLP (Mixed Integer Non Linear Programming) pour l’optimisation simultanée de la configuration et du dimensionnement d’un RCU. Aux variables continues pour l’aide au dimensionnement (température, vitesse, diamètre, aire des échangeurs), s’ajoutent des variables binaires aidant à définir la configuration du réseau (maillage et choix des technologies). La fonction objectif à minimiser est le coût total (capex et opex), qui est soumise à un ensemble de contraintes non linéaires (p. ex. pertes thermiques et de charge, bilans). La méthode développée dans ce manuscrit offre la possibilité de connecter en cascade des consommateurs n’ayant pas les mêmes besoins en température, et de réaliser des réseaux bouclés (une canalisation par tranchée). Elle permet aussi de choisir : les consommateurs à connecter au RCU, le ou les sites de production ainsi que le type de technologie utilisée. Enfin la bonne prise en compte de la physique permet de choisir le meilleur compromis entre pertes thermiques et pertes de charge, sur une large gamme de température. Cette formulation permet donc d’optimiser des réseaux de 4éme génération et de démontrer la rentabilité de l’intégration d’EnR&R sur le long terme (30 ans). Un premier travail est réalisé afin de proposer une méthodologie de résolution en plusieurs étapes permettant l’obtention de l’optimum global. Différents cas d’études académiques sont utilisés pour présenter les intérêts multiples de cette formulation. Enfin la comparaison avec un réseau existant a permis de démontrer la cohérence des résultats du modèle et a servi de base pour l’optimisation d’un cas d’étude de grande dimension. Plusieurs études de sensibilité post-optimale sont réalisées afin de démontrer l’intérêt de cet outil pour l’aide à la conception initiale ou l’extension de RCU existants. / The aim of this thesis is to develop a method that provides design assistance for District Heating Network (DHN). This tool allows simultaneously the optimization of the configuration and its sizing, thanks to an MINLP formulation (Mixed Integer Non-Linear Programming). Binary variables help to choose the optimal configuration (network layout and technologies of production), whereas continuous variables help DHN sizing (temperature, diameter, velocity, heat exchanger area, thermal generating capacity …). The objective function to minimize is the total cost (capex and opex), subjected to numerous nonlinear constraints (e.g. thermal losses, pressure drop, energy balance).This method enables to design temperature cascade between consumers, when consumer temperature requirements are different, and also looped network (only one pipe in one trench). It helps also the decision to connect (or not) consumers to the main network and also the location(s) and type(s) of the heating plant. Moreover, the arbitrage between heat losses and pressure drops is taken into account thanks to physical considerations (non-linear equations). Eventually, it is possible to design 4th generation DHN and prove their financial profitability over the long terms (30 years). First a multi-step resolution strategy is proposed to ensure finding global optimum of the complex MINLP problem. Then academic study cases are analyzed to underline the numerous assets of the formulation. Finally, the optimal design compared to an existing DHN ensures the consistency of the method and allows to build a study case at a wider scale, which can be solved thanks to the comprehensive strategy developed. The design assistance method is available for initial design as well as for extension of existing DHN.

The aim of the master's thesis is the robotic table football device modification and the design of game strategies. The thesis was extended by the design of technology for the robotic table football safety and the design of the Human Machine Interface (HMI). In the introduction so far developed solutions and presentation of the B&R Automation company are described. The following chapters describe mechanical solution modification, electrical wiring diagram design, creating simulation in the MATLAB development environment, resolving security issues and the subsequent application of a solution into the robotic table football. The conclusion of the thesis is devoted to the visualization interface design.

The aim of this master's thesis was to create a design for a prototype of a mobile robotic platform and its physical fabrication. Another goal of this master's thesis was to develop a control algorithm and its implementation into a prototype. In addition, the thesis was extended by an autonomous motion mode, an algorithm for robot path planning, and the design of the Human Machine Interface (HMI). The introduction contains a description of some already created mobile robotic platforms, a presentation of the company B&R and the theory needed to understand omnidirectional mobility. The next chapters describe the design and construction of a prototype with a selection of electronic components and their wiring, implementation of an algorithm for robot path planning, implementation of a control algorithm and design, together with the implementation of the user environment. At the end of this master's thesis, the possibilities of extending the project to future years are described.

The aim of the diploma thesis is the robotization of a conventional milling machine to a CNC milling machine using a programmable logic controller. The theoretical part of the thesis contains a description of machine tools and industry 4.0, an overview of Optimum Maschinen and B&R Automation companies, including products, and a description of the G code programming language. At the beginning of the practical part, the selected hardware, its connection and tuning of motors are described. Furthermore, the practical part explains the method of motor control and processing of CNC programs in G code. The following chapters discuss the creation of industrial visualizations for machine control and digital twin for testing purposes. The conclusion describes the evaluation of the results and indicates the possibilities for future expansion of the machine and its implementation in an automated cell in the sense of industry 4.0.