Autor: Zhou, L. - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Precision acoustic navigation for remotely operated vehicles (ROV)
Autorzy:: Zieliński, A.
Zhou, L.
Powiązania:: https://bibliotekanauki.pl/articles/985799.pdf
Data publikacji:: 2005
Wydawca:: Polskie Towarzystwo Akustyczne
Opis:: The ability to navigate a ROV to exact bottom locations or along a precise path is essential to many scientific and engineering tasks. Bottom and water column surveys along a precise and repeatable trajectory allow the monitoring of chemical and physical variables, and the study of sedimentation processes and biological phenomena. Precise navigation is also required for high-resolution synthetic sonar observations and for placement and retrieval of various devices on the bottom. This paper reviews principles behind acoustic navigation and provides a survey of commercially available Ultra-Short Baseline (USBL) navigation systems. A novel high precision navigation system is proposed that offers several advantages over the surveyed systems. Specifically, the precise position and trajectory of a ROV tethered by a cable to a bottom node is obtained using sensitive phase measurement of an acoustic signal. Proof of this concept through shallow-water and deep-water prototypes will be carried out shortly at the University of Victoria.
Źródło:: Hydroacoustics; 2005, 8; 255-264
1642-1817
Pojawia się w:: Hydroacoustics
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 2.

Tytuł:: Ocean average current measurement using acoustic phase monitoring
Autorzy:: Zieliński, A.
Zhou, L.
Butowski, M.
Powiązania:: https://bibliotekanauki.pl/articles/331688.pdf
Data publikacji:: 2008
Wydawca:: Polskie Towarzystwo Akustyczne
Tematy:: ocean-related activities
acoustic phase monitoring
hydroacoustic
Opis:: Knowledge of water currents is important in several ocean-related activities. Typically, current speed and direction are measured at a certain fixed location and depth (or depth profile) by a suitable current meter. In this paper, we propose a novel method for average current speed measurement along a path, based on acoustic phase monitoring. In this method, a transmitter and a receiver are installed at the ends of a designated path. A transmitted sinusoidal signal propagates along the path to the receiver. Intervening currents will introduce Doppler frequency shifts that can be measured as a rate of phase change in the received signal. The phase is recovered by means of a phase detector and unwrapping techniques. The desirable feature of the proposed method is that average current speed is monitored along the entire path. Moreover, the estimated frequency shift via the phase measurement achieves a higher accuracy in current measurement than does a measure of frequency directly by an FM demodulator.
Źródło:: Hydroacoustics; 2008, 11; 459-467
1642-1817
Pojawia się w:: Hydroacoustics
Dostawca treści:: Biblioteka Nauki

Artykuł

Informacja