Note
Click here to download the full example code
Piston in an infinite baffle example
# sphinx_gallery_thumbnail_path = '_static//PIB.png'
the beamshapes of mouth-emitting bat species [1,2] (among other animals eg. [3]). It’s easily to compute, but however can only describe the beamshape upto \(\pm90^{\circ}\) off-axis. One major issue with piston in an infinite baffle is that it is front-back symmetric, which is unrealistic for most animal vocalisations. Let’s see an example of what the piston model outputs:
from beamshapes import piston_in_infinite_baffle_directivity
import matplotlib.pyplot as plt
import numpy as np
The piston in an infinite baffle has two parameters k and a (for more on these parameters see here).
dB = lambda X: 20*np.log10(abs(X))
angles = np.linspace(0,np.pi,100)
k = 10.0
ka_values = np.array([1,3,5,10])
a_values = ka_values/k
parameters = {'k':k}
plt.figure()
a0 = plt.subplot(111, projection='polar')
a0.set_theta_zero_location('N')
for ka_v, a_v in zip(ka_values, a_values):
parameters['a'] = a_v
_, dirn = piston_in_infinite_baffle_directivity(angles, parameters)
plt.plot(angles, np.array(dirn), label=str(ka_v))
angles *= -1 # switch between L & R of
plt.legend(title='ka')
#plt.savefig('../docs/source/_static/PIB.png')
References
Mogensen, F., & Møhl, B. (1979). Sound radiation patterns in the frequency domain of cries from a Vespertilionid bat. Journal of comparative physiology, 134(2), 165-171.
Jakobsen, L., Ratcliffe, J. M., & Surlykke, A. (2013). Convergent acoustic field of view in echolocating bats. Nature, 493(7430), 93-96.
Macaulay, J. D., Malinka, C. E., Gillespie, D., & Madsen, P. T. (2020). High resolution three-dimensional beam radiation pattern of harbour porpoise clicks with implications for passive acoustic monitoring. The Journal of the Acoustical Society of America, 147(6), 4175-4188.
Total running time of the script: ( 0 minutes 0.000 seconds)