The capability to easily and inexpensively fabricate microfluidic devices with negligible dependence on specialized laboratory equipment continues to be one of the primary forces driving the widespread use of plastic-based devices. These devices are typically produced as replicas of a rigid mold or master incorporating a negative image of the desired structures. The negative image is typically constructed from either thick photoresists or etched silicon substrates using conventional photolithographic fabrication processes. While these micromachining techniques are effective in constructing masters with micron-sized features, the need to produce masters rapidly in order to design, fabricate, and test microfluidic devices, is a major challenge in microfluidic technology. In this research, we use inexpensive photosensitized copper clad circuit board substrates to produce master molds using conventional printed circuit technology. The techniques provide the benefits of parallel fabrication associated with photolithography without the need for cleanroom facilities, thereby offering a degree of speed and simplicity that allows microfluidic master molds to be constructed in approximately 30 minutes in any laboratory. These techniques are used to produce a variety of microfluidic channel networks using PDMS (polydimethylsiloxane) and melt-processable plastic materials.

Detta arbete har varit ett examensarbete för högskoleingenjörsprogrammet i innovationsteknik och design vid Karlstads universitet.　Examensarbetet omfattade 22,5 högskolepoäng och har utförts av Andreas Holmén.　Handledare från Karlstads universitet var industridesigner och universitetsadjunkt Lennart Wihk och examinator var proffessor Fredrik Thuvander. Examensarbetet var en del av ett större projekt som involverade ytterligare fem studenter. Projektet var ett industrisamarbete mellan Karlstads universitet, Glava energy center och företaget Värmestugan AB. Projektet är uppbyggt kring en idé om att kunna energieffektivisera uppvärmningen av tappvatten genom att kombinera solvärme- och värmepumpsteknik. Första fasen av projektet genomförde projektgruppen gemensamt, när gruppen enades om ett huvudkoncept fokuserades det på de enskilda problemformuleringarna för respektive examensarbete. Den del av projektet detta specifika arbete avsåg att lösa var vilka krav som var lämpliga för en funktionsprototyp med syftet att tilltala en investerare eller samarbetspartner. Men även hur man på bästa sätt kunde uppnå dessa krav inom tidsramen för projektet och med de resurser　som fanns tillgängliga. Uppgiften löstes genom att genomföra en research som sammanställdes med hjälp av en funktionsanalys och en semantisk analys till en kravspecifikation. Det som framkom i researchfasen användes sedan för att ta fram idéer och konstruktionsunderlag för projektets funktionsprototyp. Konstruktionen av funktionsprototypen tog upp den största delen av detta projekt eftersom det var gruppens främsta mål att tillverka en fungerande prototyp inom projektets tidsram.　 Det slutliga resultatet av detta examensarbete var en funktionsprototyp av en sol- och luft-värmepump, men även den kunskap som samlats under researchfasen och under skapandet av prototypen. / This project has been a degree project for the Bachelor of Science programme in Innovation and Design at Karlstad University. The degree project extends 22, 5 ECTS credits and has been carried out by Andreas Holmén. The academic supervisor from Karlstad University was industrial designer and lecturer Lennart Wihk and the examiner was Professor Fredrik Thuvander. The degree project was part of a bigger project involving five other students. The project was an industrial cooperation between Karlstad University, Glava energy center and Värmestugan AB. The project is built around an idea about being able to improve the energy efficiency of the heating of domestic water by combining solar heating and heat pump technology. The initial phase of the project was carried out with the whole project group together, when the group agreed on a main concept each member of the group focused on his/her specific task. This specific degree project set out to find out the requirements suitable for a functional prototype meant to accost an investor or a partner company. But also in what way these requirements could be reached within the project’s timeframe. The task was solved by making a research that was compiled by using a functional analysis and a semantic analysis resulting in a requirement specification. Later the information that emerged through the research was used to come up with ideas and design documents for the prototype. The construction of the prototype took up the largest part of this project, since it was the group’s main objective to produce a functional prototype within the projects timeframe. The final result of this project was the functional prototype of a air-air heat pump aided by the sun, but also the knowledge that was accumulated during the research phase and the making of the prototype.

The capability to easily and inexpensively fabricate microfluidic devices with negligible dependence on specialized laboratory equipment continues to be one of the primary forces driving the widespread use of plastic-based devices. These devices are typically produced as replicas of a rigid mold or master incorporating a negative image of the desired structures. The negative image is typically constructed from either thick photoresists or etched silicon substrates using conventional photolithographic fabrication processes. While these micromachining techniques are effective in constructing masters with micron-sized features, the need to produce masters rapidly in order to design, fabricate, and test microfluidic devices, is a major challenge in microfluidic technology. In this research, we use inexpensive photosensitized copper clad circuit board substrates to produce master molds using conventional printed circuit technology. The techniques provide the benefits of parallel fabrication associated with photolithography without the need for cleanroom facilities, thereby offering a degree of speed and simplicity that allows microfluidic master molds to be constructed in approximately 30 minutes in any laboratory. These techniques are used to produce a variety of microfluidic channel networks using PDMS (polydimethylsiloxane) and melt-processable plastic materials.

No description available.

With the recent advancement on robotics and CAD/CAM technologies, an articulated robot has been applied as a multi-axis CNC machine for producing complex/large prototypes. However, the single-robot machining technology can only offer limited machining capability due to its limited degrees of freedom, restricted reach and inherent singular points. To overcome the problems, a dual-robot workcell has been developed. / The development of the dual-robot workcell is presented in this thesis. It consists of four main parts, namely: kinematic modelling and postprocessor development; dual-robot programme generation and its control; robot calibration; and implementation of the system. / Kinematic models were constructed to establish the analytical description for both robots in the workcell, and therefore an accurate control of positions and orientations of each robot could be achieved in the machining process. In addition, a postprocessor was successfully developed for the dual-robot workcell to achieve the integration of three major types of five-axis machining configurations. These are the tool/workpiece-tilting type, the workpiece-tilting type and the tool-tilting type. / A robot path generation module was developed to automatically generate the programmes required for both robots to machine components. Furthermore, a PC-based distributed control architecture for the dual-robot workcell was implemented to control the robots to execute concurrent motions for machining operations. The robot controllers communicated successfully with each other via the architecture / A camera-aided method was proposed for calibrating the positioning accuracy of the dual-robot workcell. The method was implemented and provided sufficiently good results for prototyping tasks, with the calibrated accuracy approaching to the robot's repeatability. / Finally, several experiments were conducted to verify the current prototyping capability of the dual-robot workcell. From the results of prototyping spherical and sculptured surfaces, the dual-robot machining shows greater advantages over single-robot machining in terms of machining productivity and quality. / The result shows that the proposed scheme is an effective approach to complement existing CNC and single-robot machining techniques for achieving rapid and flexible prototyping. / Thesis (PhD)--University of South Australia, 2004.

Thesis (Ph.D.)--Tufts University, 2000. / Adviser: Charalabos Doumanidis. Submitted to the Dept. of Mechanical Engineering. Includes bibliographical references (leaves 118-124). Access restricted to members of the Tufts University community. Also available via the World Wide Web;

Thesis (M.S.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 14, 2008) Includes bibliographical references.

Techn. Univ., Diss--München. / Nebent.: Optimierung des SLS.

Thesis (Ph. D.)--University of Rhode Island, 2003. / Typescript. Includes bibliographical references (leaves 228-239).

Histotripsy is a nonthermal ultrasound therapy used to treat cancer noninvasively by tissue mechanical fractionation with cavitation bubble clouds. Histotripsy is conducted through focused ultrasound transducers, where the piezoceramic (PZT) plate or disc, which emits the ultrasound wave, is the fundamental unit of the transducer. For modular prototype histotripsy designs, these PZTs are housed in a 3D printed focused lens. However, 3D printing transducer components can be time consuming and expensive when scaling up manufacturing, and 3D printing is limited in material selection for transducer applications. This thesis investigates the use of a novel fabrication process for prototype focused ultrasound transducers, injection molding, with an in-house benchtop injection molding machine. Acoustic material properties for investigated injection molded materials, ABS, GPPS, 30% glass filled nylon, nylon 6/6, and nylon 101, are quantified experimentally. Single elements are constructed with injection molded lenses made from ABS, 30% glass-filled nylon, nylon 6/6, and nylon 101 on an in-house benchtop machine. Results show that injection molding is a novel feasible method for applications in focused ultrasound devices and the investigated plastics have favorable properties for developing prototype histotripsy transducers, comparable to 3D printed transducer housings. Future work aims to apply injection molding to various transducer designs and additional materials for focused ultrasound therapy devices. / Master of Science / Histotripsy is a cancer therapy that can noninvasively treat tumors without surgery. This is done through devices called focused ultrasound transducers which emit ultrasound waves to administer treatment to ablate tumors. These transducers are constructed using 3D printing methods, but this can be limiting when scaling up manufacturing or in material selection for transducer applications, therefore additional fabrication methods are needed. This thesis presents injection molding as a novel method for making transducer components with an in-house benchtop injection molding machine. Five plastic materials are investigated to determine ultrasound properties that would identify preferred transducer materials. Single element transducers are made from injection molded materials, tested, and compared with 3D printed single element transducers. Results of this thesis show that injection molding is a feasible manufacturing method capable of producing transducers for histotripsy, and researched materials have favorable properties for this application. In future research, additional injection molded materials should be investigated and multiple transducer designs created for injection molding fabrication. These injection molded transducers can be applied to histotripsy or applied to other focused ultrasound therapies.