Port Alignment Research Articles

Three-axis flexible tube sensor with LSTM-based force prediction for alignment of electric vehicle charging ports

This paper introduces a novel three-axis flexible tube sensor designed for force measurement in electric vehicle (EV) charging port alignment, utilizing long short-term memory (LSTM) networks. The research aims to develop and validate a flexible and accurate sensor system capable of predicting multi-axis forces during alignment. The sensor integrates a magnetic sensor at the center of a flexible tube to capture three-dimensional (3-D) magnetic field variations corresponding to force changes. Fabricated using thermoplastic polyurethane (TPU) via 3-D printing technology, the sensor leverages machine learning to predict force values along the , , and axes ( , , ). Finite element method (FEM) analysis was conducted to assess the deflection characteristics of the flexible tube under various force conditions. Experimental results demonstrate that integrating LSTM significantly enhances the accuracy of force prediction, achieving an R² score exceeding 97 % for all axes, with mean squared error (MSE) values of 0.2819 for the -axis, 0.3567 for the -axis, and 2.8086 for the -axis. The sensor is capable of measuring forces up to 30 N without exceeding its elastic limits. These findings highlight the sensor’s potential for improving alignment accuracy and reliability in automated EV charging systems.

Selected Papers from 4th National Aerospace Propulsion Conference NAPC 2022

The National Aerospace Propulsion Conference (NAPC) is a national conference dedicated to aerospace propulsion technologies. Two erstwhile popular conference series, the National Propulsion Conference (NPC) and the National Conference on Air-Breathing Engines (NCABE) were merged to result in NAPC. This biennial conference is intended to bring together the entire propulsion community spanning the industry, academia and the research labs nationwide. The aerospace propulsion-centred conference is considered an ideal opportunity to showcase one’s research activities with peers and foster future collaborations through networking. The 4th edition of the conference, NAPC-2022, comprised a keynote lecture, several topical invited lectures and presentations of contributed papers in parallel sessions. This special issue contains eight manuscripts selected based on peer-reviews of selected papers presented during the conference. The manuscripts broadly cover several aspects pertaining to aerospace propulsion that includes airbreathing engine components such as intakes, compressors, combustors and nozzles. From the rocket propulsion (non-airbreathing), there are papers that investigate the rocket motor grain port alignment and another paper on the heat transfer characteristics of a supersonic rocket nozzle.

Multiphysics Simulations of Microwave Induced Damage Applied to Rock Samples of Varying Strength and Absorptivity

AbstractIn this work, we show the development of a numerical model to investigate the 3D interactions between microwave radiation and basalt, granite, and sandstone rock samples. In particular, we assign sample heterogeneity based on the Weibull statistical distribution, and invoke a damage model for elemental tensile and compressive stresses based on the maximum tensile stress and the Mohr–Coulomb theories, respectively. Model implementation is facilitated by the use of comsol for use in coupling the electromagnetic, thermal, and solid displacement relations. Various parametric studies are conducted related to variable input power and waveguide port alignment, with model validation conducted with respect to damage resulting from a uniaxial compression test. The results indicate that relatively high induced temperatures will promote damage potential, but its impact must be placed within the context of the sample strength to quantify the true potential damage evolution of a given rock mass. As observed herein, a mechanically weaker rock may be prone to mechanical damage; however, it may also possess a relatively large relative permittivity, enabling it to absorb the least amount of microwave radiation thus yielding comparatively low overall damage profiles compared to a more mechanically competent rock mass.

A 3-disjoint path design of non-blocking shuffle exchange network by extra port alignment

A 3-disjoint path design of non-blocking shuffle exchange network by extra port alignment

Ergonomic port placement in robotic colorectal surgery

AbstractAimThe aim of the study was to determine how spacing between ports and alignment of ports (oblique or vertical) influences manipulation angles in robotic colorectal surgery.MethodAbdominal CT scans of 10 consecutive robotic right hemicolectomy and 10 consecutive robotic high anterior resection patients were analysed. The manipulation angles were calculated using fixed points on the preoperative abdominal coronal CT scan. Port placements were marked on the CT scan. The fixed points used to measure the manipulation angles were from the most lateral part of the caecum, hepatic flexure, splenic flexure, the descending colon/sigmoid colon junction and the sigmoid colon/rectum junction.ResultsFor right hemicolectomy and high anterior resection surgery, a port spacing of 8 cm compared with 6 cm resulted in greater manipulation angles. With 6‐cm port spacing, wider manipulation angles were not achieved with vertical port alignment compared with oblique alignment except for dissection at the splenic flexure.ConclusionsThe greatest manipulation angles were achieved with the oblique 8‐cm port spacing, which should be used in most cases.

Magnitude and dosimetric impact of inter-fractional positional variations of the metal port of tissue expanders in postmastectomy patients treated with radiation.

Postmastectomy breast reconstruction involves the insertion of a temporary tissue expander, which contains a metal injection port. The purpose of this study was to determine the magnitude and dosimetric impact of the inter-fractional positional variations of the port for patients treated with radiation. For nine breast cases treated on Tomotherapy, the deviation of the port in the daily MVCT from its reference position was measured in the three cardinal directions. The dosimetric effects of the measured errors were evaluated for two classes of error: Internal Port Error (IPE) and Patient Registration Error (PRE). For each class, dose accumulation was done for daily measured errors and a systematic error. Inter-fractional positional errors of the port were small, with 87% of the deviations below 5mm, but errors larger than 1.5cm were observed. The cumulative effect of the daily measured and systematic IPE decreased target coverage by as much as 2.8% and 3.5%, respectively. The cumulative effect of the daily measured PRE decreased target coverage by an average of 3.5%. The cumulative effect of a systematic PRE significantly decreased target coverage by an average of 16%. The presence of IPE over the course of treatment had minimal clinical impact while PRE had a greater impact on clinically-relevant regions. The robustness of treatment delivery can be improved by assigning the port its appropriate density during planning despite contouring uncertainties due to metal artefacts, and by prioritizing anatomical alignment over port alignment during daily registration.

Endovascular Repair of a Symptomatic Chronic Type A Aortic Dissection Using an Arch Branched Device

Management of ascending aortic dissections (type A) in octogenarians presents a unique surgical challenge. We present the endovascular repair of a symptomatic chronic type A aortic dissection using an arch branched device in a patient at high risk for open surgical repair. The patient is an 85-year-old man with a symptomatic, chronic type A aortic dissection and history of uncontrolled hypertension, dyslipidemia, chronic atrial fibrillation, and pulmonary hypertension. The patient originally presented 3 years earlier with an acute type B aortic dissection-penetrating aortic ulcer (PAU) and an intramural hematoma (IMH) that were initially managed medically. Follow-up computed tomographic angiography (CTA) performed for refractory pain during the same hospitalization showed enlargement of the PAU, IMH, and new pleural effusion. The patient subsequently underwent thoracic endovascular aortic repair (TEVAR) with left subclavian artery preservation. He was discharged home without complication. Surveillance CTAs at 1, 6, and 12 months were unremarkable. Follow-up CTA at 2 years demonstrated new type A dissection with focal saccular aneurysm of the ascending aorta. Primary entry tear was at the ostium of the left common carotid artery proximal to the existing TEVAR. Conservative management was initiated for prohibitive risk of open repair. The patient subsequently presented with occasional chest pain. He was considered to be a suitable candidate for endovascular repair using an arch branched device (Thoracic Branched Endosystems [TBE], W. L. Gore, Flagstaff, Ariz). Compassionate use of this investigational device was approved outside of existing protocols by the U.S. Food and Drug Administration as well as the local Institutional Review Board. Before beginning the endovascular interventions, aortic arch debranching was accomplished. Right common carotid-to-left common carotid-to-left subclavian artery bypass was performed using a 8-mm retropharyngeal tunneled Dacron graft. The proximal left common carotid artery was ligated and end-to-side anastomosis created with the distal left common carotid artery and Dacron bypass graft. An end-to-side anastomosis was then created between the Dacron graft and left subclavian artery. Next, through a percutaneous right femoral approach (26F), the innominate artery was cannulated and a buddy wire inserted. The TBE device (53 mm × 15 cm) was advanced over a stiff wire and placed into the aortic arch. To assist innominate artery branch port alignment, the buddy wire was retrieved from the right neck incision. Once adequate alignment was confirmed, the zone 0 TBE was deployed. The innominate artery branch component (20 mm × 12 mm × 6 cm) was delivered and deployed in standard fashion. Completion angiography demonstrated no evidence of endoleak. He was subsequently discharged in good condition. Treatment of high-risk patients with type A aortic dissection presents a surgical challenge. Endovascular treatment with branched devices may provide a suitable alternative to open repair in this patient population.Fig 2View Large Image Figure ViewerDownload Hi-res image Download (PPT)

NIF Target Assembly Metrology Methodology and Results

Inertial confinement fusion (ICF) experiments at the National Ignition Facility (NIF) require cryogenic targets at the 1-cm scale to be fabricated, assembled, and metrologized to micron-level tolerances. During assembly of these ICF targets, there are physical dimension metrology steps to be made of the components, subassemblies, and completed targets. Metrology is primarily completed using optical coordinate measurement machines that provide repeatable measurements with micron precision, while also allowing in-process data collection for absolute accuracy in assembly. To date, 51 targets have been assembled and metrologized, and 34 targets have been successfully fielded on NIF relying on these metrology data. In the near future, ignition experiments on NIF will require tighter tolerances and more demanding target assembly and metrology capability.Metrology methods, calculations, and uncertainty estimates will be discussed. Target diagnostic port alignment, target position, and capsule location results will be reviewed for the 2009 Energetics Campaign. The information is presented via control charts showing the effect of process improvements that were made during target production. Certain parameters, including capsule position, met the 2009 campaign specifications but will have much tighter requirements in the future. To meet these new requirements assembly process changes and metrology capability upgrades will be necessary.

The HeartSaver left ventricular assist device: an update

Ventricular assist devices have been shown to be effective as bridges to transplantation and recovery for patients with end-stage heart failure. Current technology has been limited because of the need for percutaneous connections with controllers. The HeartSaver ventricular assist device (VAD) (World Heart Corporation, Ottawa, Ontario, Canada) was developed with the intention of having a completely implantable, portable VAD system. The system consists of an electrohydraulic blood pump, internal and external battery power, and a transcutaneous energy transfer and telemetry unit that allows for power transmission through the skin. Control of the device may be achieved locally or remotely through a variety of communication systems. The device has been modified with the Series II preclinical version being available for in vitro (mock loop) and in vivo (bovine model) testing. Seventeen Series II devices have been functional on mock loops or other testing trials for an accumulated 900 days of operation. There have been eight acute experiments using a bovine model to test various components as they have become available from manufacturing. Mean pump output was 10.4 +/- 1.1 L/min in full-fill/full-eject mode. Changes in the last 24 months include (1) cannula redesign for better port alignment and integration of tissue valves; (2) battery redesign to convert to new lithium-ion cells; (3) optimized infrared information and electromagnetic inductance energy transmission through various skin thicknesses and pigmentation; and (4) improved reliability of internal and external controller hardware and software. Modifications have been required to optimize the HeartSaver VAD's performance. The final HeartSaver VAD design will be produced in the near future to allow for formal in vitro and in vivo testing before clinical implantation.

Low-cost molded packaging for optical data links

In order to lower the cost of optical data link packaging, a new technology has been developed which integrates optical and electrical components in a single, sealed, transfer molded package. This technology utilizes leadframes for low cost and mass handling. Overmolding is used for package sealing and optical port alignment. A unique process, two-step transfer molding, allows for internal shielding, intermediate IC testing, ease of assembly, and IC package sealing. An injection-molded outer housing is used for connector insertion and external shielding (through the use of conductive plastics). The first application of this technology is a high performance optical transceiver package for the growing FDDI market (125 Mb/s). With a duplex MIC connector, this package conforms to an industry standard outline and pinout. The optical transceiver easily meets full FDDI specifications. The design integrates an LED, PIN, transmitter IC, receiver IC, and two capacitors in a single, overmolded package. The final assembly sequence was conceived using the latest Design For Simplicity (DFS) principles. This paper describes the design concept and prototype model performance results. >

Expedient set-up of tangential breast fields with a simple gantry attachment

A novel technique for setting up tangential fields is described. The technique uses a simple device (Breast Aligner) which attaches to the collimator of the treatment unit. The function of the Breast Aligner is similar to conventional front and back pointers except that the beam edge rather than central ray is defined. By delineating beam entrance and exit points at the posterior field edge, the device greatly simplifies and expedites set-up, and enhances precision of port alignment. Additional advantageous features include: (a) the ability to compensate for small inadvertent variations from the initial set-up position or for patient movement between the set-up of opposing ports, (b) the ability to visually check port alignment in the treatment position immediately before irradiation, and (c) decreased chance of human and equipment error by eliminating the need for measurements and calculations at the time of treatment. Our method can be used for SSD or SAD techniques and, with minor adjustment, is applicable for establishment of coplanar cephalad field borders as required at the junction of a supraclavicular field.