The implementation of uncertainty evaluation model in manufacturability analysis system for miniature machine tool

The development of Manufacturability Analysis System for micro-machining domain (MicroMAS) is intended to address the need of the 4-axis Miniature Machine Tool (MMT) that require such system to assist the user in generating micro-component through manufacturability evaluation. One of the manufacturability aspects being assessed is the impacts from Uncertainty Evaluation Model (UEM) analysis that analyse the influence of the errors stemmed from the MMT construction on the geometrical accuracy of the machined micro-parts. The model has allowed a methodology for the errors in a custom-made MMT to be predicted and to further understand the origin of the errors on the machined micro-part. This paper reports on the implementation of UEM in the development of MicroMAS. Therefore, the results from uncertainty evaluation towards the MMT were integrated in the database which are interactively searched based on IF-THEN clauses in order to determine which rules satisfy the requirements expressed via inputs

The development of a manufacturability analysis system for micro-milling

Manufacturability analysis systems (MASs) have been developed to enable the evaluation of manufacturability aspects during the design stage. MASs have been shown to be useful for macro-manufacturing processes but less attention or effort has been put for their development in the scope of micro-manufacturing. This thesis describes the development of a MAS for a micro-machining domain (MicroMAS) with a custom-made 4-axis Miniature Machine Tool (MMT) being the scope of implementation. There are three important components in this study which are; MAS, Uncertainty Evaluation Model (UEM) and micro-milling experiments. The integration between the results from the UEM analysis and micro-machining experiments were being incorporated into the MicroMAS to provide the system with the real condition of the MMT. In MicroMAS, Primitive Feature Analysis (PFA) is introduced as a new technique in gathering information from a CAD model and analysing its manufacturability. The results from the manufacturability assessment in MicroMAS are successfully achieved through the manufacturability index which indicates the relative ease of machining the CAD model and list of related suggestions. UEM is developed to analyse the influence of the errors stemmed from the MMT construction on the geometrical accuracy of the machined micro-parts. The model has allowed a methodology for the errors in a custom-made machine tool to be predicted and to further understand the origin of the errors on the machined micro-part (either from the machine or the process itself). The abilities of the MMT are evaluated through various types of experiments where the surface quality and geometrical accuracy can be concluded to be at an acceptable range. From the experience gained from the research, the development of MicroMAS for micro-milling has been found to be practical in assisting a user to generate micro-parts using the MMT

The development of a manufacturability analysis system for micro-milling

Manufacturability analysis systems (MASs) have been developed to enable the evaluation of manufacturability aspects during the design stage. MASs have been shown to be useful for macro-manufacturing processes but less attention or effort has been put for their development in the scope of micro-manufacturing. This thesis describes the development of a MAS for a micro-machining domain (MicroMAS) with a custom-made 4-axis Miniature Machine Tool (MMT) being the scope of implementation. There are three important components in this study which are; MAS, Uncertainty Evaluation Model (UEM) and micro-milling experiments. The integration between the results from the UEM analysis and micro-machining experiments were being incorporated into the MicroMAS to provide the system with the real condition of the MMT. In MicroMAS, Primitive Feature Analysis (PFA) is introduced as a new technique in gathering information from a CAD model and analysing its manufacturability. The results from the manufacturability assessment in MicroMAS are successfully achieved through the manufacturability index which indicates the relative ease of machining the CAD model and list of related suggestions. UEM is developed to analyse the influence of the errors stemmed from the MMT construction on the geometrical accuracy of the machined micro-parts. The model has allowed a methodology for the errors in a custom-made machine tool to be predicted and to further understand the origin of the errors on the machined micro-part (either from the machine or the process itself). The abilities of the MMT are evaluated through various types of experiments where the surface quality and geometrical accuracy can be concluded to be at an acceptable range. From the experience gained from the research, the development of MicroMAS for micro-milling has been found to be practical in assisting a user to generate micro-parts using the MMT

An extensible manufacturing resource model for process integration

Driven by industrial needs and enabled by process technology and information technology, enterprise integration is rapidly shifting from information integration to process integration to improve overall performance of enterprises. Traditional resource models are established based on the needs of individual applications. They cannot effectively serve process integration which needs resources to be represented in a unified, comprehensive and flexible way to meet the needs of various applications for different business processes. This paper looks into this issue and presents a configurable and extensible resource model which can be rapidly reconfigured and extended to serve for different applications. To achieve generality, the presented resource model is established from macro level and micro level. A semantic representation method is developed to improve the flexibility and extensibility of the model

Study of orifice fabrication technologies for the liquid droplet radiator

Eleven orifice fabrication technologies potentially applicable for a liquid droplet radiator are discussed. The evaluation is focused on technologies capable of yielding 25-150 microns diameter orifices with trajectory accuracies below 5 milliradians, ultimately in arrays of up to 4000 orifices. An initial analytical screening considering factors such as trajectory accuracy, manufacturability, and hydrodynamics of orifice flow is presented. Based on this screening, four technologies were selected for experimental evaluation. A jet straightness system used to test 50-orifice arrays made by electro-discharge machining (EDM), Fotoceram, and mechanical drilling is discussed. Measurements on orifice diameter control and jet trajectory accuracy are presented and discussed. Trajectory standard deviations are in the 4.6-10.0 milliradian range. Electroforming and EDM appear to have the greatest potential for Liquid Droplet Radiator applications. The direction of a future development effort is discussed

Improving the Availability of Manufacturability Information through Decentralization of Process Planning

Process planning is part of the general product development and production process that usually follows design and precedes manufacturing. Manufacturability and process planning information in general play central role in many product development and production activities, including paradoxically, conceptual and detail design - the activities that take place before process planning. The need of conducting some of the process planning activities formally before or during design is thus rather obvious. One of the main research issues is therefore the identification of the process planning activities that can be performed before the traditional process planning phase and handling of the process planning information so as to adequately provide the designers with the manufacturability informationneeded during conceptual and detail design. Another issue is how to support collaboration during process planning and how to maintain continuity of the process planning tasks. This paper suggests the decentralization of the process planning task and proposes the execution of the process planning activities in a piecemeal fashion, starting right afterreceiving an order and specifying the requirements for a product. Process planning under the proposed procedure consists of six semi-autonomous sub-phases, some of which comprise activities that must be conducted prior to the process planning phase. This helps to overcome the problem of timely availability of manufacturability information during the execution of upstream and downstream product development and production activities. The paper alsoproposes a computer-based method of handling the manufacturability information generated in various stages of the product development and production process. A database design and structure of prototype software that manages the process planning information are presented and discussed. Furthermore, a case study conducted to explore howthe proposed process planning procedure could be put in use is presented and discussed

Leveraging manufacturing process capability in integrated product development

Thesis (S.M.)--Massachusetts Institute of Technology, Sloan School of Management; and, Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1998.Includes bibliographical references (p. 73-74).by Charles E. Hix, Eric B. Kittleson.S.M

TE10 R-TE11c input coupler for a low-THz gyro-TWA

The design of a fundamental rectangular-to-circular coaxial cavity input coupler for a low-THz gyro-traveling wave amplifier (TWA) is presented. Theoretical and numerical approaches to the design of the coaxial cavity input coupler are introduced. The design is optimized for operation between 360-384 GHz, achieving a transmission bandwidth of 7.5% (358-386 GHz). A comment on the manufacturability of sub-mm waveguide channels is included

Design of a wireless ureteropyeloscope

Ureteroscopy is a form of endoscopy that concerns itself with the urinary system. Flexible ureteropyeloscopes are instruments used to access the urinary system for diagnostic and therapeutic procedures. An average ureteropyeloscope requires a repair for every 3 to 13 hours of use, or alternatively 6 to 15 procedures. Therefore, there is a need to increase the durability of the ureteropyeloscope to lower the frequency of repairs required. In addition, the number of cables in the workspace needs to be reduced for improved handling by the clinician. The present study details the design of an ureteropyeloscope, which is modelled after currently existing instruments. Current endoscopes use fibre-optics for lighting area of interest as well as image acquisition. However, the ureteropyeloscope discussed was developed with a camera at the distal end of the insertion tube as its image acquisition system. The images captured were transmitted to a monitor for viewing via a wireless transmission module. The ureteropyeloscope discussed in the study was aimed at increasing the durability of the deflection unit of the ureteropyeloscope, with primary component made of nitinol, and reducing the number of cables around the workstation by using wireless means to transmit images from image acquisition system to monitor