Freehand 3D ultrasound imaging system using electromagnetic tracking
Ultrasound imaging is a non-invasive, real-time, low-cost, effective imaging modality for diagnosing and managing a variety of diseases. Most ultrasound-based clinical procedures are performed using conventional two-dimensional (2D) ultrasound images. However, accurate visualization and analysis of the three-dimensional (3D) anatomy using a sequence of 2D ultrasound images is often challenging. To overcome this challenge, several approaches have been proposed for 3D ultrasound imaging. This study contributes to these ongoing efforts by describing a freehand 3D ultrasound imaging system based on a conventional 2D ultrasound machine and a 3D electromagnetic tracking system. The synthesized 3D ultrasound volumes are visualized using the Visualization Toolkit (VTK) open-source library and the ParaView open-source application. The feasibility of our freehand 3D ultrasound imaging system is demonstrated by imaging a double cross-wire phantom.
Dependence on the prior magnetic map become one of the key problems which restrict the development of the geomagnetic navigation. This paper inspired from the animal navigation behavior which dispense with the priori geomagnetic map. First, we generalize the bio-inspired navigation process as a multi-objective problems. Then, present a stress evolution search AUV navigation model for the particularity of geomagnetic navigation, which make multi-objective problem solving search combine with navigation movement to achieve the purpose of navigation. Finally, compared the present model with a gradient descent model with part priori geomagnetic map. The simulation results show that the proposed algorithm allows the AUV to navigate efficiently using geomagnetic information without prior map. The proposed algorithm offers insights into the research and application of the biologically inspired geomagnetic navigation.