title: Laser 3-D measuring system and real-time visual feedback for teaching and correcting breathing.
abstract: We present a novel method for real-time 3-D body-shape measurement during breathing based on the laser multiple-line triangulation principle. The laser projector illuminates the measured surface with a pattern of 33 equally inclined light planes. Simultaneously, the camera records the distorted light pattern from a different viewpoint. The acquired images are transferred to a personal computer, where the 3-D surface reconstruction, shape analysis, and display are performed in real time. The measured surface displacements are displayed with a color palette, which enables visual feedback to the patient while breathing is being taught. The measuring range is approximately 400×600×500 mm in width, height, and depth, respectively, and the accuracy of the calibrated apparatus is ±0.7 mm. The system was evaluated by means of its capability to distinguish between different breathing patterns. The accuracy of the measured volumes of chest-wall deformation during breathing was verified using standard methods of volume measurements. The results show that the presented 3-D measuring system with visual feedback has great potential as a diagnostic and training assistance tool when monitoring and evaluating the breathing pattern, because it offers a simple and effective method of graphical communication with the patient.
authors.affiliation: University of Ljubljana, Faculty of Mechanical Engineering, Aškerčeva 6, 1000 Ljubljana, Slovenia. klemen.povsic@fs.uni-lj.si
authors.forename: Klemen
authors.initials: K
authors.lastname: Povšič
authors.forename: Matjaž
authors.initials: M
authors.lastname: Fležar
authors.forename: Janez
authors.initials: J
authors.lastname: Možina
authors.forename: Matija
authors.initials: M
authors.lastname: Jezeršek
mesh_terms: D000328:Adult; D002138:Calibration; D056228:Feedback, Sensory; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007834:Lasers; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods*; D015203:Reproducibility of Results; D015656:Respiratory Mechanics / Q000502:physiology*; D012815:Signal Processing, Computer-Assisted; D013147:Spirometry / Q000379:methods*; D060726:Torso / Q000033:anatomy & histology / Q000502:physiology