title: Navigation within buildings: novel movement detection algorithms supporting people with visual impairments.
abstract: This study aimed at finding simple algorithms to identify three different movements registered by accelerometer and to detect differences in the acceleration signals of people with and without visual impairments. The Tactile Acoustical Navigation and Information Assistant (TANIA) is construed to provide persons suffering from visual impairments support for an independent navigation indoors and outdoors. Attaining this goal, TANIA uses vertical acceleration signal extrema to assess its user's walking distance. This study investigated first the sit-to-stand movement, stumbling and walking up- and down stairs of 25 subjects with visual impairments using TANIA sensor system. The objective was to improve the user's movement detection using sensors to get valid and reliable data. In a second step of the study it was investigated if there is a difference between the above-mentioned movements in people with or without visual impairments (n=10). The acceleration signals of the subjects were compared. Three simple algorithms were found, which are able to separate the movement signals based on accelerometers of the respective daily movements. The second step analysis revealed a detectable difference in the second phase of stumbling (p=.034), where the subjects had to get back into walking forward. No differences in the other acceleration signals were found.
authors.affiliation: Institute of Sportsciences, Goethe-University, Ginnheimer Landstraße 39, D-60487 Frankfurt am Main, Germany. Electronic address: Sina.David01@gmail.com.
authors.forename: Sina
authors.initials: S
authors.lastname: David
authors.affiliation: Juni-Prof. Institute of Sport- and Exercise Science, Allmandring 28, University of Stuttgart, D-70569 Stuttgart, Germany. Electronic address: Schmitt@inspo.uni-stuttgart.de.
authors.forename: Syn
authors.initials: S
authors.lastname: Schmitt
authors.affiliation: Julianne Utz, Holzhauserstr. 13, D-70563 Stuttgart, Germany. Electronic address: Julianne.utz@googl.com.
authors.forename: Julianne
authors.initials: J
authors.lastname: Utz
authors.affiliation: BNI Blindnavigation International, Ayestraße 2, D-88441 Mittelbiberach, Germany. Electronic address: andreas.hub@blindnavigation.org.
authors.forename: Andreas
authors.initials: A
authors.lastname: Hub
authors.affiliation: Prof., Institute of Sport and Exercise Science, Chair Exercise and Health Sciences, University of Stuttgart, Nobelstraße 15, D-70569 Stuttgart, Germany. Electronic address: wolfgang.schlicht@inspo.uni-stuttgart.de.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schlicht
mesh_terms: D061725:Accelerometry / Q000295:instrumentation / Q000379:methods*; D000328:Adult; D000368:Aged; D000465:Algorithms; D001766:Blindness / Q000534:rehabilitation*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012656:Self-Help Devices; D065854:Spatial Navigation; D055815:Young Adult
keywords: Accelerometer; Movement detection; Navigation; Visual impairment