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Robotic automation of CNC machines is becoming more popular as robot technology advances and becomes more readily available. While some CNC machines can run autonomously with part catchers, vertical milling centers require an external entity to keep the machine running. Collaborative and Industrial robots are the two main selections for automating a vertical CNC milling machine. We investigate specifically which robot type is most effective for machine tending a Haas VF2 vertical milling center. To do this a cell floor plan, risk assessment, overall equipment effectiveness evaluation, and a total cost analysis are performed to compare robots. With this results of each analysis process, it appears the industrial robot is most effective for the machine tending case.

The main goal of this thesis is to propose a strategy which can integrate the precision hydrodynamic polishing system with an ordinary CNC machine tool. This integrated CNC machine tool is capable of applying the hydrodynamic polishing process, which is a high-precision machining method, to compensate the form error on a work surface to improve its form precision. With such a compensation capability, a low-cost CNC machine tool may play the function of precision machining as well as an expensive CNC machine tool does. It is hoped that with this function equipped in a CNC machine tool the international competition of the domestic machining industry can be enhanced. The complete integrating scheme is composed of three parts. The first part is the hardware of polishing system, which is required to attach to the CNC machine tool. The second one is the software developed in this thesis. It includes the codes to generate the commands to control the CNC machine tool and the attached polishing system. The final one is coordinating system that is to synchronize the actions of the CNC machine tool and polishing system. It is done by requiring the polishing system to match the actions of machine tool through measuring the configuration of machine tool consistently. Because of the first and third parts, no modification to the machine tool is needed and the requirement to read the internal information of CNC controller is waved. This will significantly reduce the complexity in implementing the integrating job. When properly integrated with the required sensors, the software developed in this thesis can harmonize the actions of the polishing system and machine tool to execute the form error compensation task. The software will automatically generate the commands for the polishing system and machine tool based on the geometric and material data of work. It does not require the user to fully comprehend the function of the CAM software and the details of polishing process. This will obviously reduce the skill requirement of operator and facilitate the use of the integrated system. Since the CNC machine tool only plays the function of offering the three translational motions (in X, Y, and Z directions), the application of this strategy to an ordinary CNC machine tool is straightforward.

The goal of this thesis is to develop a novel polishing tool system. This system can be attached to a CNC machine and execute a precision polishing job mainly for an axially symmetric free surface. The precision polishing job is to remove the error surface profile on the work to improve its form precision, which was left by the previous machining process. An inferential rule, which was based on a top-down planning strategy, was utilized to gradually decompose the design goals of the tool system to facilitate the process for generating all of the possible design proposals. The major design goal is to render all the rotational axes of the tool system to exactly intersect at the tool center. To analyze the effects of the structure and interface stiffness of tool system on the major goal, the finite element method was adopted. Further, the homogeneous transformation scheme is applied to establish the forward kinematic error of the designed system and to analyze the effect of different manufacturing and assembly errors on the major goal.Accordingly, two novel polishing tool systems were developed. The simulation study indicated that the total errors after assembly at the tool center and the two rotation axes were dominated by the stiffness at the interfaces of the tool system, in addition to the influence of structure stiffness. An assembly strategy was then proposed in the study to reduce the total error.

This master's thesis is aimed on the analysis during of the contractin company, followed by focusing on weakness and administration proposal to improve them. The aim is to optimize the course of the contract the company, with the consequent creation of added value for the producer and for the customer.

Today’s   market   is   subjected   to   numerous   changes   due   to   the   need   of   continuous improvement  of  different  commercial  brands  in  order  to  survive  against  competitors.  This competition  drives  the  evolution  of  industrial  processes,  to  satisfy  the  high  customers’ requirements. It means that factors such as flexibility, adaptability and agility are crucial for the  successful  development  of  industries,  which  experience  some  degrees  of  uncertainty due  to  machine  breakdowns,  delays  and  market  fluctuations  among  others.  The  current trend  in  manufacturing  industries  consists  in  the  implementation  of  distributed  control systems (DCS), substituting the earlier programmable logic controllers (PLC) systems where a main  processor  operated  as  the  central  unit  of  the  system.  To  this  end,  the  application  of function  blocks  (FB)  compliant  with  the  IEC  61499  standard  represents  an  innovative technique  for  dealing  with  the  design  and  programming  of  DCSs.  These  FBs  enable  the creation  of  event-driven  networks  governed  by  embedded  algorithms  that  can  be  used  to enhance  the  flexibility  and  portability  of  industrial  job-shops  based  on  a  distributed architecture.  Job-shop  floors  represent  a  principal  concept  in  manufacturing  industries.  This  project  is focused on the integration of a computer numerically controlled (CNC) machine and a gantry robot  which  must  be  coordinated  and  cooperate  for  the  achievement  of  an  industrial machining  and  assembly  process.  It  implies  the  design  of  a  PLC-managed  distributed  cell using  nxtControl  software.  This  software  facilitates  the  construction  of  FBs-networks  to control both machines and enables the communication process via service interface function blocks (SI-FB). Likewise, the whole process will be monitored using an interface also created within nxtControl which will allow the operator to decide the batch and characteristics of the production.  This project is also intended to set the basis for the understanding of the FB concept defined in  IEC  61499  which  moves  away  from  earlier  scan-based  systems  to  event-driven  models, aiming to contribute to the development of future research in the function blocks area.

Current survey has showed that people with disability need equal work opportunity. Meanwhile, labor shortage is becoming more and more serious in existing manufacturing industry and there is less physical work involved in CNC machine operation. Thus it is a good opportunity for people with disability to work in manufacturing industry as CNC operators. In the preliminary research, observation, interview and domain research were conducted to understand activates of FVMC (Fadal Vertical Machining Center is a type of CNC machine) operators. Researchers found the existing FVMC are very inconvenient to use, because most of them were designed for the general public. Operator's performance was restricted by the poor design of the machines and the work area. As a result, many people, especially wheel chair users have found limited employment opportunities in the manufacturing industry. To address this problem, on one hand, we presented a study on the current FVMC. A Full size FVMC was mocked up and 9 wheelchair users and 6 able-body users participated in this study. They were asked to mimic to finish the tasks relate to FVMC operation. This study also aims at collecting data for universal FVMC design. On the other hand, based on the preliminary research two concept of FVMC design scenarios are also developed and evaluated by two groups of subjects. This study addressed limitations of wheelchair users with respect to CNC operation, especially reaching issues, and collected data about the preferred FVMC settings and design from wheelchair users and able-bodied people. At the end, design guidelines were developed for machine engineers or designers in two aspects: 1) improve currently available FVMC; 2) redesign FVMC that is safer and easier to use. These guidelines will increase the potential of employing wheelchair users alongside able-bodied people in the manufacturing industry.

Stretchable Electronics is an emerging class of electronics that allow electronics to be bent, conform, ex and stretch while still retaining its full functionality. Other than bending, existing and conforming, adding stretchability to electronic systems can open up a new frontier for a myriad of applications. Especially in the medical sector, these stretchable devices can increase the scope of monitoring and ease and comfort of the patient. All kinds of wearable devices can be based on these technologies to augment our daily lives. With the kind of state of art technology available to the common man today, the bar has already been set for the performance of such devices. Hence, its imperative that these stretchable devices perform at this level and should be capable of adapting to the market to serve the mass requirement. Hence, it becomes inevitable to use metal interconnects to provide very low resistance and easy adhesion to commercial electronic components. Another aspect of such devices is an adhesion ability with which we can attach it to various kinds of surfaces. In this thesis, we propose a new multi-layered PDMS structure approach to bring stretchability in the device. For all kinds of adhesion requirements, various ratios of PDMS: Cross-linker have been used. These different ratios of PDMS: Cross-linker changes the mechanical and adhesive properties of the cured PDMS. Hence, the same material can be used as the stretchable substrate as well as to serve various adhesion requirements. A soft adhesion allows us to attach it to the human body/other surfaces. The adhesion can be tailored to be quite conformal and strong, yet its removal is quite gentle to the skin. A higher curing ratio makes the PDMS very sticky and soft. Aluminum/Copper foils can be directly stuck upon it and tracks can be then etched out to get a printed circuit. Since this adhesive layer is quite soft, it acts as a cushion and reduces the amount of stress transferred to the metal interconnects. Hence, stretchable circuits with metal interconnects can be realized. The electronic components can be then attached upon it via normal soldering techniques/using conductive ink. Various devices that can be built with the proposed techniques have been coined the term CAS (Conformal Active Sheets) to allow easy reference to such kind of devices. Since the substrate is soft, physical handling of such devices becomes an issue as one tries to transfer the circuit pattern. Hence, direct etching of the metal foil was explored via high pulsed current discharge technique. A CNC machine was also designed to try various ways of direct etching of the metal foil in an accurate and repeatable fashion.

The topic of this work is the design of a vertical lathe with a table diameter of 2,500 mm. Part of the work is the analysis of current products in order to solve their shortcomings. The result is an innovative design focused on user-friendly operation and progressive shaping. At the same time, the designed machine fulfils all technical, ergonomic and aesthetic requirements.