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Tracking Sensors (tracking + sensor)

Distribution by Scientific Domains

Medical Sciences	75%

Selected Abstracts

Visual Tracking and LIDAR Relative Positioning for Automated Launch and Recovery of an Unmanned Rotorcraft from Ships at Sea

NAVAL ENGINEERS JOURNAL, Issue 2 2009
MATT GARRATT
Sensors and systems for a fully autonomous unmanned helicopter have been developed with the aim of completely automating the landing and launch of a small-unmanned helicopter from the deck of a ship. For our scheme, we have combined a laser rangefinder (LRF) system with a visual tracking sensor to construct a low-cost guidance system. Our novel LRF system determines both the distance to and the orientation of the deck in one cycle. We have constructed an optical sensor to complement the laser system, comprising a digital camera interfaced to a Field Programmable Gate Array (FPGA), which enables the entire target tracking computation to be achieved in a very small self-contained form factor. A narrowband light source on the deck is detected by the digital camera and tracked by an algorithm implemented on the FPGA to provide a relative bearing to the deck from the helicopter. By combining the optical sensor bearing with the information from the laser system, an accurate estimate of the helicopter position relative to the deck can be found. [source]

Skeleton-based active catheter navigation

THE INTERNATIONAL JOURNAL OF MEDICAL ROBOTICS AND COMPUTER ASSISTED SURGERY, Issue 2 2009
Yili Fu
Abstract Background The emergence of the active catheter has prompted the development of catheterization in minimally invasive surgery. However, it is still operated using only the physician's vision; information supplied by the guiding image and tracking sensors has not been fully utilized. Methods In order to supply the active catheter with more useful information for automatic navigation, we extract the skeleton of blood vessels by means of an improved distance transform method, and then present the crucial geometric information determining navigation. With the help of tracking sensors' position and pose information, two operations, advancement in the proximal end and direction selection in the distal end, are alternately implemented to insert the active catheter into a target blood vessel. Results The skeleton of the aortic arch reconstructed from slice images is extracted fast and automatically. A navigation path is generated on the skeleton by manually selecting the start and target points, and smoothed with the cubic cardinal spline curve. Crucial geometric information determining navigation is presented, as well as requirements for the catheter entering the target blood vessel. Using a shape memory alloy active catheter integrated with magnetic sensors, an experiment is carried out in a vascular model, in which the catheter is successfully inserted from the ascending aorta, via the aortic arch, into the brachiocephalic trunk. Conclusions The navigation strategy proposed in this paper is feasible and has the advantage of increasing the automation of catheterization, enhancing the manoeuvrability of the active catheter and providing the guiding image with desirable interactivity. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Teaching Mass Casualty Triage Skills Using Immersive Three-dimensional Virtual Reality

ACADEMIC EMERGENCY MEDICINE, Issue 11 2008
Dale S. Vincent MD
Abstract Objectives:, Virtual reality (VR) environments offer potential advantages over traditional paper methods, manikin simulation, and live drills for mass casualty training and assessment. The authors measured the acquisition of triage skills by novice learners after exposing them to three sequential scenarios (A, B, and C) of five simulated patients each in a fully immersed three-dimensional VR environment. The hypothesis was that learners would improve in speed, accuracy, and self-efficacy. Methods:, Twenty-four medical students were taught principles of mass casualty triage using three short podcasts, followed by an immersive VR exercise in which learners donned a head-mounted display (HMD) and three motion tracking sensors, one for their head and one for each hand. They used a gesture-based command system to interact with multiple VR casualties. For triage score, one point was awarded for each correctly identified main problem, required intervention, and triage category. For intervention score, one point was awarded for each correct VR intervention. Scores were analyzed using one-way analysis of variance (ANOVA) for each student. Before and after surveys were used to measure self-efficacy and reaction to the training. Results:, Four students were excluded from analysis due to participation in a recent triage research program. Results from 20 students were analyzed. Triage scores and intervention scores improved significantly during Scenario B (p < 0.001). Time to complete each scenario decreased significantly from A (8:10 minutes) to B (5:14 minutes; p < 0.001) and from B to C (3:58 minutes; p < 0.001). Self-efficacy improved significantly in the areas of prioritizing treatment, prioritizing resources, identifying high-risk patients, and beliefs about learning to be an effective first responder. Conclusions:, Novice learners demonstrated improved triage and intervention scores, speed, and self-efficacy during an iterative, fully immersed VR triage experience. [source]