Polo-Lopez, Lucas, Masa-Campos, Jose L., and Ruiz-Cruz, Jorge A.
International Journal of RF and Microwave Computer-Aided Engineering. Dec 2019, Vol. 29 Issue 12, n/a
Satellite communications, Antennas (Electronics) -- Design and construction, Waveguides -- Design and construction, Sintering, 3D printing, and Computer-aided design
Keywords: additive manufacturing; fused filament fabrication; phase shifter; reconfigurable; selective laser sintering; waveguide Abstract This work presents the design and manufacturing of a K-band reconfigurable phase shifter completely implemented in waveguide technology for reduced insertion loss, good matching, and large phase shifting range. The device is based on the combination of a short slot coupler and two tunable reactive loads implemented as a section of short-circuited waveguide where an adjustable metallic post is inserted. Three prototypes of this design have been manufactured using different techniques (conventional computer numerical control machining, a low-cost fused filament fabrication technique and direct metal laser sintering) in order to assess its performance for different applications. The prototypes have been characterized experimentally and the achieved results are evaluated and compared. The proposed phase shifter, since it is fully developed in waveguide technology, eliminates the need of adding transitions to planar structures in order to integrate lumped components like pin diodes or varactors. Therefore, this device has a great potential in high-power beam steering phased arrays. Biographical information: Lucas Polo-Lopez received the BSc and MSc degrees in Telecommunication Engineering from the Universidad Autonoma de Madrid, Madrid, Spain in 2014 and 2016, respectively. Since 2015 he has been with the Radiofrequency Circuits, Antennas and Systems (RFCAS) group of this same university, where he works toward the PhD degree. His current research interests include the computer-aided design of horn antennas and passive waveguide devices, as well as the application of additive manufacturing techniques to the construction of waveguide devices. Jose L. Masa-Campos received the Master degree in 1999 and the PhD Degree in 2006, from the Universidad Politecnica de Madrid, Spain. From 1999 to 2003 he developed his professional activity in the R&D department of the company RYMSA with the design of base station antennas for mobile communications and satellite antennas. From 2002 to 2003 he directed the R&D department of RYMSA. From 2003 to 2007, he worked as Researcher for Universidad Politecnica de Madrid, and in 2005 he joined to Universidad Autonoma de Madrid as Associate Professor in the Radiofrequency Circuits, Antennas and Systems (RFCAS) group. His main current research interests are in active and passive planar array antennas. Jorge A. Ruiz-Cruz received the Ingeniero de Telecomunicacion degree and the PhD degree from the Universidad Politecnica de Madrid, Madrid, Spain, in 1999 and 2005, respectively. Since 2006, he has been with the Universidad Autonoma de Madrid, Madrid, where he became an Associate Professor in 2009. His current research interests include the computer-aided design of microwave passive devices and circuits (filters, multiplexers, and orthomodes). Byline: Lucas Polo-Lopez,Jose L. Masa-Campos,Jorge A. Ruiz-Cruz
The International Journal of Medical Robotics and Computer Assisted Surgery. Feb 2020, Vol. 16 Issue 1, n/a
Image processing, Rapid prototyping, Tumors, Computer-aided design, and Osteotomy
Keywords: computer-aided design; customized implant; customized surgical osteotomy guide; rapid prototyping; virtual surgical planning Abstract Objectives The objective of this study was to provide the generalized methodology for design and development of a customized implant and customized surgical osteotomy guide (CSOG) for precise mandibular tumor resection and placement of a customized implant in ablative tumor surgery for accurate mandibular reconstruction. Methods Medical imaging technique, image processing, virtual surgical planning (VSP), biomedical computer-aided design (CAD), and rapid prototyping (RP) were used to develop CSOG and customized implant. A mock surgical test and an experimental analysis were performed on the biomodel (RP assisted diseased model) to check the effectiveness of the CSOG. Results The paired t test showed the statistically significant result with the use of CSOG as compared to the without using CSOG in ablative mandibular tumor surgery. Conclusions A mock test and an experimental analysis proved that, the precise tumor resection and customized implant placement with minimal gap between bone-implant junctions in mandibular reconstruction using CSOG. Byline: Sandeep Dahake, Abhaykumar Kuthe,Mahesh Mawale, Pranav Sapkal, Ashutosh Bagde, Subodh Daronde, Manish Kamble, Bhupesh Sarode