3D integrated microfluid devices are a group of engineered microelectromechanical systems (MEMS) whereby the feature size and operating range of the components are on a microscale. These devices or systems have the ability to detect, control, activate, and create macroscale effects. On this basis, microfluidic chips are systems that enable microliters and smaller volumes of fluids to be controlled and moved within microscale-sized (one-millionth of a meter) channels. While this small scale can be compared to microfluid chips of larger applications, such as pipes or plumbing practices, their small size is commonly useful in controlling and monitoring the flow of fluid. Through such applications, microfluidic chip technology has become a popular tool for analysis in biochemistry and bioengineering with their most recent uses for artificial organ production. For this purpose, microfluidic chips can be instantly controlled by the human body, such as pulse, blood flow, blood pressure, and transmitting data such as location and the programmed agents. Despite its vast uses, the production of microfluidic chips has been mostly dependent upon conventional practices that are costly and often time consuming. More recently, however, 3D printing technology has been incorporated in rapidly prototyping microfluid chips at microscale for major uses. This state-of-the-art review highlights the recent advancements in the field of 3D printing technology for the rapid fabrication, and therefore mass production, of the microfluid chips.

Sensors have become an integral part of our everyday lives by helping us converting packets of data to make important decisions. Due to this reason, researches are done constantly to improve the fabrication processes of sensors by making them more user-friendly, less time-consuming, and more cost-effective. The application of any fabrication solution that offers those advantages will have a major impact on the manufacturing of modern sensors. To address this issue, a 3D printed Surface Acoustic Wave (SAW) temperature sensor is presented in this paper. The modelling and analysis of such a sensor have been performed for both aluminium and copper electrodes using COMSOL software. In total, 4 different sensing structures, 2 each for both aluminium and copper electrodes based one-port resonators, are designed and analysed for their application in temperature sensing. The resulting responses of those sensors are approximately 2.19 MHz and 424.01 MHz frequency ranges. The novelty lies in the possibility of mass-producing such a sensor using additive manufacturing will have a direct impact in the areas where conventional electronics cannot be utilized.

Fault Diagnosis on Bevel Gearbox with Neural Networks and Feature Extraction

Continuous developments in the field of 3D printing techniques and equipment have enabled their usage in the field of electronics structures, circuits, and device fabrication in addition to many other fields. This advancement has enabled the potential fabrication of sensors using silicon-based micro or even Nanoelectronics. Currently, the manufacturing and packaging of such devices and structures are heavily reliant on lithography, which can be slow and can involve substantial processing requirements. In this paper, a temperature-sensing Interdigital Transducer (IDT) structure was designed and fabricated using Direct Laser Writing (DLW) based on Two-Photon Lithography (TPL), which is a high-resolution 3D printing technology. The TPL in a positive photoresist was combined with the physical vapor deposition method and the lift-off process to create gold IDT microstructures. The developed sensing structures were characterized using a network analyzer to determine the resonance frequency and its dependence on the temperature changes. The results showed that the IDT structures exhibit a linear response toward the changes in temperature with an average sensitivity of 0.123 MHz/°C. The most important advantage in producing the IDT structure with the additive manufacturing technique is that a very small-sized structure is produced error-free and efficiently.