Processing range data for reverse engineering and virtual reality

Author(s):  
S. Karbacher ◽  
X. Laboureux ◽  
N. Schon ◽  
G. Hausler
2001 ◽  
Vol 1 (4) ◽  
pp. 282-290 ◽  
Author(s):  
F. C. Langbein ◽  
B. I. Mills ◽  
A. D. Marshall ◽  
R. R. Martin

Current reverse engineering systems can generate boundary representation (B-rep) models from 3D range data. Such models suffer from inaccuracies caused by noise in the input data and algorithms. The quality of reverse engineered geometric models can be improved by finding candidate shape regularities in such a model, and constraining the model to meet a suitable subset of them, in a post-processing step called beautification. This paper discusses algorithms to detect such approximate regularities in terms of similarities between feature objects describing properties of faces, edges and vertices, and small groups of these elements in a B-rep model with only planar, spherical, cylindrical, conical and toroidal faces. For each group of similar feature objects they also seek special feature objects which may represent the group, e.g. an integer value which approximates the radius of similar cylinders. Experiments show that the regularities found by the algorithms include the desired regularities as well as spurious regularities, which can be limited by an appropriate choice of tolerances.


Computer ◽  
2014 ◽  
Vol 47 (7) ◽  
pp. 38-45 ◽  
Author(s):  
John R. Stowers ◽  
Anton Fuhrmann ◽  
Maximilian Hofbauer ◽  
Martin Streinzer ◽  
Axel Schmid ◽  
...  

Author(s):  
Mingshao Zhang ◽  
Zhou Zhang ◽  
Yizhe Chang ◽  
El-Sayed Aziz ◽  
Sven Esche ◽  
...  

Virtual Reality (VR) is a well-known concept and has been proven to be beneficial in various areas. However, several disadvantages inherent in VR prevent its broad deployment in the educational arena. These limitations include non-realistic representation, lack of customizability and flexibility, financial feasibility, physical and psychological discomforts of the users, simulator sickness, etc. In this paper, an innovative method that uses the Microsoft Kinect as an essential component for developing game-based VR educational laboratories is presented. This technique addresses three different aspects. First, it represents an efficient method for creating the VE using the Kinect as a measuring tool. Second, the Kinect is employed as a substitute DAQ system for acquiring range data and tracking the motion of objects of interest. At last, the Kinect serves as a novel human-computer interface for tracking the users’ entire body motion and recognizing their voices. Using the method described here, three major aspects of educational VR development can be accomplished with an inexpensive and commercially available Kinect.


2008 ◽  
Vol 45 ◽  
pp. 161-176 ◽  
Author(s):  
Eduardo D. Sontag

This paper discusses a theoretical method for the “reverse engineering” of networks based solely on steady-state (and quasi-steady-state) data.


2004 ◽  
Vol 63 (3) ◽  
pp. 143-149 ◽  
Author(s):  
Fred W. Mast ◽  
Charles M. Oman

The role of top-down processing on the horizontal-vertical line length illusion was examined by means of an ambiguous room with dual visual verticals. In one of the test conditions, the subjects were cued to one of the two verticals and were instructed to cognitively reassign the apparent vertical to the cued orientation. When they have mentally adjusted their perception, two lines in a plus sign configuration appeared and the subjects had to evaluate which line was longer. The results showed that the line length appeared longer when it was aligned with the direction of the vertical currently perceived by the subject. This study provides a demonstration that top-down processing influences lower level visual processing mechanisms. In another test condition, the subjects had all perceptual cues available and the influence was even stronger.


Swiss Surgery ◽  
2002 ◽  
Vol 8 (6) ◽  
pp. 250-254
Author(s):  
Vogelbach ◽  
Bogdan ◽  
Rosenthal ◽  
Pfefferkorn ◽  
Triponez

Fragestellung: Die dieser Untersuchung zugrunde liegende Frage war, ob das angewandte Ausbildungskonzept geeignet war, um am Beispiel der Einführung der laparoskopischen Cholezystektomie eine neue Operationsmethode in einer universitären Ausbildungsklinik mit einer grossen Anzahl Chirurgen zu etablieren. Patienten und Methodik: Seit Einführung der ersten laparoskopischen Cholezystektomie wurden alle Cholezystektomien während zwei Jahren (Mai 1990 bis Mai 1992) prospektiv erfasst. Ein Ausbildungskonzept wurde gewählt, bei dem jeweils ein Operateur durch einen Tutor geschult wurde und so 15 konsekutive Eingriffe durchführte, um dann die Technik einem weiteren auszubildenden Chirurgen zu instruieren. Resultate: In zwei Jahren wurden 355 Patienten cholezystektomiert. 60% der Operationen wurden laparoskopisch durchgeführt oder begonnen. 40% der Operationen wurden offen durchgeführt. In den ersten zwei Jahren konnten 13 Operateure (durchschnittlich 16 Operationen / Operateur , range 1 - 60) in die neue Technik eingeführt werden. Es traten keine schweren Komplikationen, insbesondere keine Gallenwegsverletzungen in dieser Einführungsphase auf. Diskussion: In der Literatur wird dieses Vorgehen bei der Einführungsphase seit 1992 wiederholt vorgestellt, diskutiert und empfohlen. Zwischenzeitlich gibt es Richtlinien von Fachgesellschaften und nationalen Institutionen, welche die Ausbildung zur Ausführung neuer chirurgischer Techniken reglementieren. In den letzten Jahren verlagern sich die ersten Ausbildungsschritte in Richtung Trainingskurse an skill-stations und virtual reality Trainer. Schlussfolgerung: Das beschriebene Ausbildungskonzept bewährte sich in der Einführungsphase der laparoskopischen Cholezystektomie zu Beginn der 90er-Jahre.


Dreaming ◽  
2018 ◽  
Vol 28 (3) ◽  
pp. 205-224 ◽  
Author(s):  
Patrick McNamara ◽  
Kendra Holt Moore ◽  
Yiannis Papelis ◽  
Saikou Diallo ◽  
Wesley J. Wildman
Keyword(s):  

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