An Evaluation of the Aurora System as a Flesh-Point Tracking Tool for Speech Production Research Purpose Northern Digital Instruments (NDI; Waterloo, Ontario, Canada) manufactures a commercially available magnetometer device called Aurora that features real-time display of sensor position tracked in 3 dimensions. To test its potential for speech production research, data were collected to assess the measurement accuracy and reliability of the system. ... Research Note
Research Note  |   August 01, 2008
An Evaluation of the Aurora System as a Flesh-Point Tracking Tool for Speech Production Research
 
Author Affiliations & Notes
  • Bernd J. Kröger
    University Hospital Aachen, Germany, and Aachen University, Germany
  • Marianne Pouplier
    Institute of Phonetics and Speech Processing, Ludwig-Maximilians-University of Munich, Germany
  • Mark K. Tiede
    Haskins Laboratories, New Haven, CT, and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge
  • Contact author: Bernd J. Kröger, Department of Phoniatrics, Pedaudiology, and Communication Disorders, University Hospital Aachen and Aachen University, Pauwelsstraβe 30, 52074 Aachen, Germany. E-mail: bkroeger@ukaachen.de.
Article Information
Speech, Voice & Prosody / Speech / Research Note
Research Note   |   August 01, 2008
An Evaluation of the Aurora System as a Flesh-Point Tracking Tool for Speech Production Research
Journal of Speech, Language, and Hearing Research, August 2008, Vol. 51, 914-921. doi:10.1044/1092-4388(2008/067)
History: Received May 25, 2007 , Accepted November 29, 2007
 
Journal of Speech, Language, and Hearing Research, August 2008, Vol. 51, 914-921. doi:10.1044/1092-4388(2008/067)
History: Received May 25, 2007; Accepted November 29, 2007

Purpose Northern Digital Instruments (NDI; Waterloo, Ontario, Canada) manufactures a commercially available magnetometer device called Aurora that features real-time display of sensor position tracked in 3 dimensions. To test its potential for speech production research, data were collected to assess the measurement accuracy and reliability of the system.

Method First, sensors affixed at a known distance on a rigid ruler were moved systematically through the measurement space. Second, sensors attached to the speech articulators of a human participant were tracked during various speech tasks.

Results In the ruler task, results showed mean distance errors of less than 1 mm, with some sensitivity to location within the measurement field. In the speech tasks, Euclidean distance between jaw-mounted sensors showed comparable accuracy; however, a high incidence of missing samples was observed, positively correlated with sensor velocity.

Conclusions The real-time positional feedback provided by the system makes it potentially useful in speech therapy applications. The overall missing data rate observed during speech tasks makes use of the system in its current form problematic for the quantitative measurement of speech articulator movements; however, NDI is actively working to improve the Aurora system for use in this context.

Acknowledgments
Work in part was supported by the 6th European Framework Programme. Northern Digital Instruments (Waterloo, Ontario, Canada) kindly let us borrow their Aurora system for this evaluation and provided technical support.
Order a Subscription
Pay Per View
Entire Journal of Speech, Language, and Hearing Research content & archive
24-hour access
This Article
24-hour access