A New Position Feedback Method for Manufacturing Equipment

2008 ◽  
Author(s):  
Chan Wong ◽  
Carlos Montes ◽  
Laine Mears ◽  
John Ziegert
Keyword(s):  
Digital Images ◽  
Liquid Crystal Display ◽  
Digital Camera ◽  
Position Sensing ◽  
Test Platform ◽  
Position Feedback ◽  
Feedback Method ◽  
Future Work ◽  
Pixel Matrix ◽  
Noise Reduction Algorithm

This paper presents an innovative real time 2-dimensional position feedback method, which processes visual input data from a target image on an actively-controlled planar pixel matrix. The objective is to demonstrate the ability to position an X-Y stage with high resolution, using direct position sensing of a dynamically controlled image. In order to achieve high spatial resolution using a pixel array as a target, an algorithm that processes both the geometric shape and the grayscale intensities of the image is implemented. The test platform consists of an X-Y stage carrying a Liquid Crystal Display (LCD) screen that is imaged by a stationary digital camera. The pixel intensities on the LCD screen are modified dynamically to provide 2-dimensional position command inputs that translate to the desired stage motion. The digital images acquired by the camera are used to provide position error feedback to the controller. Experimental results show that direct position sensing is possible to a certain degree of accuracy. However, in order to match today’s CNC machines’ accuracy levels further processing of the digital images is required. A noise reduction algorithm to filter the fluctuations of the measurements in the digital images is proposed as future work, as well as other considerations.

ACCURACY ANALYSIS OF DIFFERENT SURFACE RECONSTRUCTION MODELLING METHODS FOR HERITAGE OBJECTS DIGITIZED CONSIDERING PHOTOGRAMMETRIC DATA / SKIRTINGŲ RELJEFO MODELIAVIMO METODŲ, SUDARYTŲ PAGAL PAVELDO OBJEKTO FOTOGRAMETRINIUS DUOMENIS, TIKSLUMO ANALIZĖ / АНАЛИЗ ТОЧНОСТИ РАЗНЫХ МЕТОДОВ МОДЕЛИРОВАНИЯ ПОВЕРХНОСТИ, СОСТАВЛЕННЫХ В СООТВЕТСТВИИ С ФОТОГРАММЕТРИЧЕСКИМИ ДАННЫМИ ОБЪЕКТА АРХИТЕКТУРНОГО НАСЛЕДИЯ

2011 ◽  
Vol 37 (2) ◽  
pp. 56-62
Author(s):  
Jūratė Sužiedelytė-Visockienė ◽  
Aušra Kumetaitienė ◽  
Renata Bagdžiūnaitė
Keyword(s):  
Initial Data ◽  
Surface Reconstruction ◽  
Digital Images ◽  
Digital Camera ◽  
Accuracy Analysis ◽  
Triangulated Irregular Network ◽  
Modelling Analysis ◽  
The University ◽  
Modelling Methods ◽  
Made In

The article explains the possibilities of reconstructing heritage objects. Measurements were made using photogrammetric data received from digital images taken by the Canon EOS 1D Mark III digital camera calibrated in the Institute of Photogrammetry at the University of Bonn (Germany). The images were received applying the PhotoMod photogrammetric software produced in Russia. TIN (Triangulated Irregular Network) and an orthophoto map were made in the investigated objects. The modelling analysis of TIN data was made using ArcGIS software. The purpose of the article is to reconstruct the surface of heritage objects referring to photogrammetric data, to investigate accuracy dependence of heritage object reflection on the methods of preparing the initial data and to evaluate the influence of modelling methods on to the accuracy of reconstructing heritage objects when modelling photogrammetric data and selecting the most appropriate method of modelling parameters to restore the most accurate surface of the heritage object. Santrauka Straipsnyje aprašomos paveldo – architektūrinio objekto paviršiaus modeliavimo galimybės. Modeliavimas atliktas pagal fotogrametrinius objekto duomenis–skaitmenines nuotraukas, darytas kalibruota fotokamera Canon EOS 1D Mark III. Kamera kalibruota Bonos universiteto Fotogrametrijos institute (Vokietija). Objekto nuotraukos apdorotos fotogrametrine kompiuterine programa PhotoMod (Rusija). Sudaryta objekto ortofotografinė nuotrauka ir, parenkant skirtingus duomenų šaltinius, paviršiaus TIN (triangulated irregular network). Skirtingais metodais, naudojantis ArcGIS programa, atliktas fotogrametrinių TIN duomenų modeliavimas ir gauti objekto paviršiaus vaizdai. Įvertintas rezultatų tikslumas ir kokybė. Резюме Описываются возможности моделирования поверхности объекта архитектурного наследия. Моделирование осуществляется с использованием фотограмметрических данных объекта – цифровых снимков, снятых калибрированной цифровой камерой Canon EOS 1D Mark III. Камера калибрирована в Институте фотограмметрии Боннского университета (Германия). Снимки объекта обработаны по фотограмметрической компьютерной программе PhotoMod (Россия). Cделан ортофотографический снимок объекта и с помощью разных источников данных TIN (Triangulated Irregular Network) поверхности. Используя программу ArcGIS, разными методами проведено моделирование фотограмметрических TIN данных и получены изображения поверхности объекта. Осуществлена оценка точности и качества результатов.

The Future of Telepathology for the Developing World

2011 ◽  
Vol 135 (2) ◽  
pp. 211-214 ◽  
Author(s):  
Charles L Hitchcock
Keyword(s):  
Health Care ◽  
Patient Care ◽  
Digital Images ◽  
Virtual Slide ◽  
Digital Camera ◽  
Improve Patient Care ◽  
Limited Resources ◽  
Software Application ◽  
Open Platform ◽  
Delays In Diagnosis

Abstract Physician shortages are acute in developing countries, where disease burden is the greatest and resources for health care are very limited. A lack of pathologists in these countries has lead to delays in diagnosis and misdiagnoses that adversely affect patient care and survival. The introduction of telepathology into countries with limited resources for health care is but one of multiple approaches that can be used to alleviate the problem. Telepathology is the electronic transmission of digital images that can be used for education and diagnostic consultation. A basic system consists of a microscope with a mounted digital camera linked to a computer. The ability to produce histologic slides, to repair and maintain equipment, and to provide training are also needed for the successful use of this technology. iPath is a Web-based, open platform, software application which was developed at the University of Basel, Switzerland, for telepathology and which brings together pathologists from around the world to provide telepathology support for diagnostic consultation and provides education to centers with limited resources. The use of virtual-slide technology to provide a digital image of an entire glass slide is another technology for diagnostic consultation and pathology education. This technology requires more costly resources to support it, which may limit its utility in many areas. Telepathology can generate collections of digital images and virtual slides needed for training indigenous pathologists in their countries to become self-sufficient. Thus, the long-term goal of this technology is to improve patient care and survival.

Digital Images + Interactive Software = Enjoyable, Real Mathematics Modeling

2008 ◽  
Vol 101 (8) ◽  
pp. 568-572
Author(s):  
Andy Ventress
Keyword(s):  
Mathematical Modeling ◽  
Real World ◽  
Digital Images ◽  
Digital Camera ◽  
Mathematical Activity ◽  
Motivation To Learn ◽  
Interactive Software ◽  
Student Records

Mathematical modeling begins with a phenomenon, and what better way to represent a real-world phenomenon than with a digital camera? When a student records an image with a digital camera rather than doing an exercise from a textbook, that student becomes the owner of his own mathematical activity. Because the problem is now the student's, he or she has considerably more motivation to learn the mathematics.

FPGA-Based Relative Distance Estimation for Indoor Robot Control Using Monocular Digital Camera

2010 ◽  
Vol 14 (6) ◽  
pp. 714-721 ◽  
Author(s):  
Ying-Hao Yu ◽  
◽  
Chau Vo-Ky ◽  
Sarath Kodagoda ◽  
Quang Phuc Ha ◽  
...  
Keyword(s):  
Embedded System ◽  
Liquid Crystal Display ◽  
Thin Film Transistor ◽  
Digital Camera ◽  
Distance Estimation ◽  
Active Vision ◽  
Relative Distance ◽  
Camera System ◽  
Require Time ◽  
Field Programmable

Distance measurement methodologies based on the digital camera usually require time-consuming calibration procedures, some are even derived from complicated image processing algorithms resulting in low picture frame rates. In a dynamic camera system, due to the unpredictability of intrinsic and extrinsic parameters, odometric results are highly dependent on the quality of extra sensors. In this paper, a simple and efficient algorithm is proposed for relative distance estimation in robotic active vision by using a monocular digital camera. Accuracy of the estimation is achieved by judging the 2D perspective projection image ratio of the robot labels obtained on a TFT-LCD (Thin Film Transistor – Liquid Crystal Display) monitor without the need of any additional sensory cost and complicated calibration effort. Further, the proposed algorithm does not contain any trigonometric functions so that it can be easily implemented on an embedded system using the Field Programmable Gate Array (FPGA) technology. Experimental results are included to demonstrate the effectiveness of the technique.

Dead Time Compensation for a Novel Positioning System via Predictive Controls and Virtual Intermittent Setpoints

2009 ◽  
Author(s):  
Chan Wong ◽  
Laine Mears ◽  
John Ziegert
Keyword(s):  
Predictive Control ◽  
Dead Time ◽  
Vision System ◽  
Liquid Crystal Display ◽  
Digital Camera ◽  
Motion Controller ◽  
New Class ◽  
System A ◽  
Time Problem ◽  
Dead Time Compensation

Predictive control and intermittent setpoints are proposed to overcome the dead time that problem occurs in a new class of high precision position sensor for manufacturing equipment. In place of a rotary encoder or linear glass scale, a combination of a digital camera and a Liquid Crystal Display (LCD) screen is used to actively monitor two dimensional position changes on an XY table. In order to achieve precise spatial resolution, an actively-controlled planar pixel matrix is used as the tracking target for the system. A digital camera senses the location of the moving image displayed on the LCD screen and provides 2 dimensional position feedback. Thus, the timing and the quality of the visual feedback to the controller are the significant factors to determine the accuracy of the system. Due to the long image processing time, the vision feedback of the actual position of the stage is delayed. At the same time, with the slow frame capturing rates of the camera, dead time occurs between consecutive acquisitions of feedback signals from the vision system to the motion controller, which is detrimental to the performance of the system. Hence, studies and detailed analysis on different dead time compensation strategies and path planning algorithms have been performed to select the optimal strategy to address these challenges. Based on simulation results, a proposed method for integrating predictive control with virtual intermittent setpoints algorithm to mitigate dead time problem is presented in the final section of the paper.

scholarly journals Using Interactive Multimedia to Enhance Student Access to Information on Plant Anatomy and Cell Biology

HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 432B-432
Author(s):  
Robert L. Geneve
Keyword(s):  
Cell Biology ◽  
Growth And Development ◽  
Interactive Multimedia ◽  
Digital Images ◽  
Digital Camera ◽  
Cell Types ◽  
Plant Anatomy ◽  
Easy Access ◽  
Horticultural Crops ◽  
Student Access

An interactive multimedia presentation was developed using authoring software (Authorware from Macromedia) to provide information on plant anatomy and cell biology. Our current course in growth and development of horticultural crops has limited time and lab facilities available for these subjects, yet a good foundation in this area is important to understanding growth and development. This software uses a variety of techniques, including color digital images, illustrations, cartoon animation, and video, to teach aspects of cell biology and different plant cell types. In addition, a review session allows students to interactively test their knowledge of the subject. The software was placed on a Dept. of Horticulture server that provided student access to a folder for course work. Students were able to access the software from anywhere on campus via the University network. Multiple students can use the software simultaneously. The approach of using a local server provided easy access and avoided some of the delays involved with viewing large (1 mb) images found when using the World Wide Web. It took students several weeks to complete the software's modules. Then, students completed an independent plant anatomy lab using the software for reference. Students were required to create a virtual notebook of labeled digital images captured from prepared microscope slides using a microscope attached with a digital camera and linked to a computer. Students found this approach to learning to be challenging, and initial feedback has been very positive.

scholarly journals 3D MODELING WITH PHOTOGRAMMETRY BY UAVS AND MODEL QUALITY VERIFICATION

2017 ◽  
Vol IV-4/W4 ◽  
pp. 129-134 ◽  
Author(s):  
V. Barrile ◽  
G. Bilotta ◽  
A. Nunnari
Keyword(s):  
3D Modeling ◽  
Laser Scanning ◽  
Digital Images ◽  
Digital Camera ◽  
Terrestrial Laser Scanning ◽  
3D Models ◽  
Model Quality ◽  
Department Of Agriculture ◽  
Dense Cloud ◽  
Study Case

This paper deals with a test lead by Geomatics laboratory (DICEAM, Mediterranea University of Reggio Calabria), concerning the application of UAV photogrammetry for survey, monitoring and checking. The study case relies with the surroundings of the Department of Agriculture Sciences. In the last years, such area was interested by landslides and survey activities carried out to take the phenomenon under control. For this purpose, a set of digital images were acquired through a UAV equipped with a digital camera and GPS. Successively, the processing for the production of a 3D georeferenced model was performed by using the commercial software Agisoft PhotoScan. Similarly, the use of a terrestrial laser scanning technique allowed to product dense cloud and 3D models of the same area. To assess the accuracy of the UAV-derived 3D models, a comparison between image and range-based methods was performed.

Image Compression in Morphometry Studies Requiring 21 CFR Part 11 Compliance: Procedure Is Key with TIFFs and Various JPEG Compression Strengths

2004 ◽  
Vol 32 (2) ◽  
pp. 258-263 ◽  
Author(s):  
Mark W. Tengowski
Keyword(s):  
Image Analysis ◽  
Image Compression ◽  
Digital Images ◽  
Digital Camera ◽  
Jpeg Compression ◽  
Work Flow ◽  
Analysis Software ◽  
Compressed Images ◽  
Electron Microscope Grid ◽  
Individual Data Point

This study aims to compare the integrity and reproducibility of measurements created from uncompressed and compressed digital images in order to implement compliance with 21 CFR Part 11 for image analysis studies executed using 21 CFR Part 58 compliant capture systems. Images of a 400-mesh electron microscope grid and H&E stained rat liver tissue were captured on an upright microscope with digital camera using commercially available analysis software. Digital images were stored as either uncompressed TIFFs or in one of five different levels of JPEG compression. The grid images were analyzed with automatic detection of bright objects while the liver images were segmented using color cube-based morphometry techniques, respectively, using commercially-available image analysis software? When comparing the feature-extracted measurements from the TIFF uncompressed to the JPEG compressed images, the data suggest that JPEG compression does not alter the accuracy or reliability to reproduce individual data point measurements in all but the highest compression levels. There is, however, discordance if the initial measure was obtained with a TIFF format and subsequently saved as one of the JPEG levels, suggesting that the use of compression must precede feature extraction. It is a common practice in software packages to work with TIFF uncompressed images. However, this study suggests that the use of JPEG compression as part of the analysis work flow was an acceptable practice for these images and features. Investigators applying image file compression to other organ images will need to validate the utility of image compression in their work flow. A procedure to digitally acquire and JPEG compress images prior to image analysis has the potential to reduce file archiving demands without compromising reproducibility of data.

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