An echolocation visualization and interface system for dolphin research

• Published in: The Journal of the Acoustical Society of America Vol. 123; no. 2; pp. 1188 - 1194
• Main Authors: Amundin, Mats, Starkhammar, Josefin, Evander, Mikael, Almqvist, Monica, Lindström, Kjell, Persson, Hans W.
• Format: Journal Article
• Language: English
• Published: Woodbury, NY Acoustical Society of America 01.02.2008; American Institute of Physics
• Subjects: Acoustic signal processing; Acoustics; Animal Communication; Animals; Audiovisual Aids; Computer Terminals; Data Display; Dolphins - physiology; Dolphins - psychology; Echolocation - physiology; Engineering and Technology; Ethology - instrumentation; Ethology - methods; Exact sciences and technology; Feedback, Psychological; Fundamental areas of phenomenology (including applications); Image Processing, Computer-Assisted - instrumentation; Medical Engineering; Medicinteknik; NATURAL SCIENCES; NATURVETENSKAP; Physics; Software; Symbolism; Teknik; Underwater sound; User-Computer Interface; Marine animal; Visualization; Vertebrata; Mammalia; Cetacea; Underwater acoustics; Echolocation
• ISSN: 0001-4966; 1520-8524; 1520-8524
• DOI: 10.1121/1.2828213

The present study describes the development and testing of a tool for dolphin research. This tool was able to visualize the dolphin echolocation signals as well as function as an acoustically operated "touch screen." The system consisted of a matrix of hydrophones attached to a semitransparent screen, which was lowered in front of an underwater acrylic panel in a dolphin pool. When a dolphin aimed its sonar beam at the screen, the hydrophones measured the received sound pressure levels. These hydrophone signals were then transferred to a computer where they were translated into a video image that corresponds to the dynamic sound pressure variations in the sonar beam and the location of the beam axis. There was a continuous projection of the image back onto the hydrophone matrix screen, giving the dolphin an immediate visual feedback to its sonar output. The system offers a whole new experimental methodology in dolphin research and since it is software-based, many different kinds of scientific questions can be addressed. The results were promising and motivate further development of the system and studies of sonar and cognitive abilities of dolphins.