Vorträge und Posterpräsentationen (mit Tagungsband-Eintrag):
G. Kaniak, J. Mitaroff, H. Schweinzer:
"Combining Two Independent Methods for Ultrasonic Echo Direction Estimation";
Vortrag: EAA - EuroRegio,
Ljubljana, Slovenia;
15.09.2010
- 18.09.2010; in: "1stEAA - EuroRegio 2010, Congress on Sound and Vibration",
(2010),
ISBN: 978-961-269-283-4.
Kurzfassung englisch:
Activities of our group are directed to high precision ultrasonic distance measurement in air using broadband transducers and correlative signal processing. The goal is 3D scene analysis in air for robotic applications by ultrasound echolocation. To measure the direction of the reflected signal in 3D, a compact sensor is set up with four microphones arranged as a cross, each of them in 40mm distance to the centred transducer. Transmitting chirp signals, this transducer enables to measure the time-of-flights of the received echoes with high resolution and allows calculating the direction of the reflected signal with good accuracy. The compact design ensures a determination of the refleciton point independent of the geometry of the object. The angle- and frequency-dependent radiation pattern of the transducer results in characteristic phase shifts within the chirp signal, which can be used to determine the angel of transmission. An angle dtermination algorithm based on correlation was developed that deals with the lack of ratational symmetry in the radiation pattern of commercial available transducers. The combination of the direction information delivered by these two methods allows detecting multipath propagation to avoid erroneous results.
Erstellt aus der Publikationsdatenbank der Technischen Universität Wien.