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In this paper, the concept, fabrication, activation and testing of a novel synchronous micropump based on microfabricated copper coils and polymer magnets are presented. The pump works by the synchronized rotation of two polymer magnets in an annular SU-8 microfluidic channel. Magnet rotation is achieved by sequentially activating a set of planar coils to repel or attract the first magnet (traveling magnet) through the channel, while the second one is anchored between the inlet and the outlet ports. At the end of each pumping cycle, the magnets exchange their anchored and traveling functions. The synchronization of magnet rotation has been achieved through programming two activation schemes that proved the high dependence of the pump operation and performance on employed activation scheme parameters. The magnetic forces exerted from electroplated coils on the polymer magnet were tested experimentally using a three-dimensional force sensor. Different coil dimensions have been investigated. A maximum force of 658 μN at an applied current of 138 mA was achieved. The micropump has successfully pumped water with rotational speeds up to 83.33 rpm. Water flow rates in the range of 17.3 μL min −1 at 31.25 rpm to 158.7 μL min −1 at 83.33 rpm were achieved.

Function logic methods have been successfully used in Value Analysis (VA) and Value Engineering (VE) for several decades. This functional approach attempts to provide a common language for specialists in multiple domains. This paper describes an extension of function logic that assists in systematic identification of design functions, allocations, and their interrelations. Our approach identifies a three-level function/allocation/component information structure to represent the state of the design. We illustrate new types of links that exist between functions and the effect of these on the representation of the interrelated functions. These linkages provide new pathways for design information and function evaluation through allocation arithmetic and supported functions. A computational model of the conceptual design process is proposed based on the extended function logic design representation. An outline of the inputs, outputs and operations on form and function variables is given as a step prior to the synthesis process. We illustrate, by example, the process of translating functional representations across specialist domains. Finally, a computer-based aid to developing functional models is described.

A new viscous spiral micropump which uses the surface micromachining technology is introduced. The paper outlines the design of a spiral pump fabricated in five levels of polysilicon using Sandia’s Ultraplanar Multilevel MEMS Technology (SUMMiT), and presents an analytical solution of the flow field in its spiral channel. The pump characteristics are obtained experimentally for a scaled-up prototype and are found to be in good agreement with the results obtained using the analytical model.