Sonar beam Animations for

“Sonar beam pattern of a flying bat as it tracks tethered insects”
K.Ghose and C.F. Moss, J. Acoust. Soc. Am., V 144, No 2, August 2003



Note: All animation files are less than 4 MB.
They are in wmv format, Window Media Player will play them.




Animation

Description

2001.09.18.2.01 5.8 MB
(top view animation)

2001.09.18.2.01_split 12.8 MB
(animation with camera view)

2001.09.18.2.01_split_polar 12.8 MB
(animation of polar shape beam pattern, with camera view)

The bat flies in from the far end of the array. The worm is dropped into the flight space at frame 78. The bat directs its beam initially to the left of its flight path upto frame 132, then starts to ping in the direction of the target (ahead of it) from frame 143 onwards. It increases its repetition rate noticably from frame 169 onwards. The 2001.09.18.2.01_split animation shows the view from one of the infra-red cameras. The 2001.09.18.2.01_split_polar animation shows polar plots of the beam pattern

2001.10.02.1.01 12.7 MB
(top view animation)

2001.10.02.1.01_split 28 MB

The bat takes a sharp turn to its right, flying towards the room center. The target is dropped from the trap door in frame 100. The bat first directs its beam towards the target at frame 199, and makes a sharp turn left to try and intercept it. The bat hits the target but fails to capture it. The target remains swinging on the tether. The bat flies past, then makes a sharp $180^{o}$ turn starting at frame 406 and directs its beam in the direction of the target. It picks up pursuit of the target at frame 535, noticably increasing its repetition rate at frame 545. This attempt ends in a successful capture.

2002.08.20.3.02 5.4 MB
(top view animation)

The bat flies towards the center of the room. The black square represents an inedible block of foam. The bat vocalizes ahead of its flight path. The target is dropped at frame 25. The bat initially ``inspects'' the inedible foam block (frames 119 to 181) then directs its beam to the target from frame 184 onwards.

2001.06.12.1.03 9 MB
(top view animation)

The bat attempts to capture a tethered meal worm being moved in a circle about .5 m in diameter. The bat keeps its beam centered on the target throughout, even though it gives up pursuit after making a complete circuit. Beam pattern data is not available for part of the pursuit (during which the beam was directed where there were no microphones).



© Batlab 2003
http://www.batlab.umd.edu/jasa03/