Fused Filament Fabrication (FFF) for Manufacturing of Microfluidic Micromixers: An Experimental Study on the Effect of Process Variables in Printed Microfluidic Micromixers.

The need for accessible and inexpensive microfluidic devices requires new manufacturing methods and materials as a replacement for traditional soft lithography and polydimethylsiloxane (PDMS). Recently, with the advent of modern additive manufacturing (AM) techniques, 3D printing has attracted attention for its use in the fabrication of microfluidic devices and due to its automated, assembly-free 3D fabrication, rapidly decreasing cost, and fast-improving resolution and throughput. Here, fused filament fabrication (FFF) 3D printing was used to create microfluidic micromixers and enhance the mixing process, which has been identified as a challenge in microfluidic devices. A design of experiment (DoE) was performed on the effects of studied parameters in devices that were printed by FFF. The results of the colorimetric approach showed the effects of different parameters on the mixing process and on the enhancement of the mixing performance in printed devices. The presence of the geometrical features on the microchannels can act as ridges due to the nature of the FFF process. In comparison to passive and active methods, no complexity was added in the fabrication process, and the ridges are an inherent property of the FFF process.

A Fast and Low-Cost Human Body 3D Scanner Using 100 Cameras.

The human body is one of the most complicated objects to model because of its complex features, non-rigidity, and the time required to take body measurements. Basic technologies available in this field range from small and low-cost scanners that must be moved around the body to large and high-cost scanners that can capture all sides of the body simultaneously. This paper presents an image-based scanning system which employs the structure-from-motion method. The design and development process of the scanner includes its physical structure, electronic components, and the algorithms used for extracting 3D data. In addition to the accuracy, which is one of the main parameters to consider when choosing a 3D scanner, the time and cost of the system are among the most important parameters for evaluating a scanner system in the field of human scanning. Because of the non-static nature of the human body, the scanning time is particularly important. On the other hand, a high-cost system may lead to limited use of such systems. The design developed in this paper, which utilizes 100 cameras, facilitates the acquisition of geometric data in a fraction of a second (0.001 s) and provides the capabilities of large, freestanding scanners at a price akin to that of smaller, mobile ones.

On the Impact of the Fabrication Method on the Performance of 3D Printed Mixers.

A wide variety of 3D printing technologies have been used for the fabrication of lab-on-a-chip (LOC) devices in recent years. Despite the large number of studies having examined the use of 3D printing technologies in microfluidic devices, the effect of the fabrication method on their performance has received little attention. In this paper, a comparison is shown between unibody-LOC micro-mixers, a particular type of monolithic design for 3D printed LOCs, fabricated in polyjet, stereolithography (SLA) and fused deposition modelling (FDM or FFF) platforms, paying particular attention to the inherent limitations of each fabrication platform and how these affect the performance of the manufactured devices.