Multi-baseline interferometer broadband real-time phase calibration method

Author(s):  
Yue-tao Han ◽  
Pan Wei-ping ◽  
Wei Cui ◽  
Wang Jun
2011 ◽  
Vol 25 (8) ◽  
pp. 682-687
Author(s):  
Yuetao Han ◽  
Siliang Wu ◽  
Weiping Pan ◽  
Fan Yang

Author(s):  
Zachary Baum

Purpose: Augmented reality overlay systems can be used to project a CT image directly onto a patient during procedures. They have been actively trialed for computer-guided procedures, however they have not become commonplace in practice due to restrictions of previous systems. Previous systems have not been handheld, and have had complicated calibration procedures. We put forward a handheld tablet-based system for assisting with needle interventions. Methods: The system consists of a tablet display and a 3-D printed reusable and customizable frame. A simple and accurate calibration method was designed to align the patient to the projected image. The entire system is tracked via camera, with respect to the patient, and the projected image is updated in real time as the system is moved around the region of interest. Results: The resulting system allowed for 0.99mm mean position error in the plane of the image, and a mean position error of 0.61mm out of the plane of the image. This accuracy was thought to be clinically acceptable for tool using computer-guidance in several procedures that involve musculoskeletal needle placements. Conclusion: Our calibration method was developed and tested using the designed handheld system. Our results illustrate the potential for the use of augmented reality handheld systems in computer-guided needle procedures. 


2010 ◽  
Author(s):  
Pierre Tremblay ◽  
Louis Belhumeur ◽  
Martin Chamberland ◽  
André Villemaire ◽  
Patrick Dubois ◽  
...  

2018 ◽  
Vol 81 (2) ◽  
pp. 839-851 ◽  
Author(s):  
Shuyu Tang ◽  
Eugene Milshteyn ◽  
Galen Reed ◽  
Jeremy Gordon ◽  
Robert Bok ◽  
...  

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Helio Koiti Kuga ◽  
Valdemir Carrara

Attitude control of artificial satellites is dependent on information provided by its attitude determination process. This paper presents the implementation and tests of a fully self-contained algorithm for the attitude determination using magnetometers and accelerometers, for application on a satellite simulator based on frictionless air bearing tables. However, it is known that magnetometers and accelerometers need to be calibrated so as to allow that measurements are used to their ultimate accuracy. A calibration method is implemented which proves to be essential for improving attitude determination accuracy. For the stepwise real-time attitude determination, it was used the well-known QUEST algorithm which yields quick response with reduced computer resources. The algorithms are tested and qualified with actual data collected on the streets under controlled situations. For such street runaways, the experiment employs a solid-state magnetoresistive magnetometer and an IMU navigation block consisting of triads of accelerometers and gyros, with MEMS technology. A GPS receiver is used to record positional information. The collected measurements are processed through the developed algorithms, and comparisons are made for attitude determination using calibrated and noncalibrated data. The results show that the attitude accuracy reaches the requirements for real-time operation for satellite simulator platforms.


2022 ◽  
pp. 1-1
Author(s):  
Chuanlong Guan ◽  
Ran Zhang ◽  
Jinkui Chu ◽  
Ze Liu ◽  
Yuanyi Fan ◽  
...  

2019 ◽  
Vol 90 (1) ◽  
pp. 015118 ◽  
Author(s):  
Hao Zeng ◽  
Peng Ye ◽  
Wentao Wei ◽  
Lianping Guo ◽  
Huiqing Pan ◽  
...  

Optik ◽  
2021 ◽  
Vol 225 ◽  
pp. 165731
Author(s):  
Zhongguang Yang ◽  
Xiaocheng Zhu ◽  
Zhiming Cai ◽  
Wen Chen ◽  
Jinpei Yu

2017 ◽  
Vol 10 (5) ◽  
pp. 1755-1768 ◽  
Author(s):  
Ellis Shipley Robinson ◽  
Ru-Shan Gao ◽  
Joshua P. Schwarz ◽  
David W. Fahey ◽  
Anne E. Perring

Abstract. Real-time, single-particle fluorescence instruments used to detect atmospheric bioaerosol particles are increasingly common, yet no standard fluorescence calibration method exists for this technique. This gap limits the utility of these instruments as quantitative tools and complicates comparisons between different measurement campaigns. To address this need, we have developed a method to produce size-selected particles with a known mass of fluorophore, which we use to calibrate the fluorescence detection of a Wideband Integrated Bioaerosol Sensor (WIBS-4A). We use mixed tryptophan–ammonium sulfate particles to calibrate one detector (FL1; excitation  =  280 nm, emission  =  310–400 nm) and pure quinine particles to calibrate the other (FL2; excitation  =  280 nm, emission  =  420–650 nm). The relationship between fluorescence and mass for the mixed tryptophan–ammonium sulfate particles is linear, while that for the pure quinine particles is nonlinear, likely indicating that not all of the quinine mass contributes to the observed fluorescence. Nonetheless, both materials produce a repeatable response between observed fluorescence and particle mass. This procedure allows users to set the detector gains to achieve a known absolute response, calculate the limits of detection for a given instrument, improve the repeatability of the instrumental setup, and facilitate intercomparisons between different instruments. We recommend calibration of single-particle fluorescence instruments using these methods.


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