A room from OBJ files¶
A room and a table read from OBJ files, one acoustic object per OBJ group, the table as a free-standing obstacle, simulated with image sources and ray tracing and analysed.
"""A room from OBJ files.
A room and a table read from OBJ files, one acoustic object per OBJ group, the table as a free-standing
obstacle, simulated with image sources and ray tracing and analysed.
"""
import os
import compas_acoustics as ca
########### create a source and receivers
source = ca.Source(x=1.5, y=3.0, z=1.5, name="source_1")
receiver_1 = ca.Receiver(x=2.0, y=2.0, z=1.0, name="receiver_1")
# receiver_2 = ca.Receiver(x=6.0, y=4.0, z=1.0, name="receiver_2")
########### create a scene
scene = ca.Scene(name="Demo Scene", description="This is a demo scene.")
########### add the source and receiver to the scene
scene.add_source(source)
scene.add_receiver(receiver_1)
# scene.add_receiver(receiver_2)
########### what are the scene's surface groups?
# scene.print_scene_materials()
########### create acoustic materials
concrete = ca.AcousticMaterial(name='concrete', absorption_coefficients=[0.01, 0.01, 0.02, 0.02, 0.02, 0.05, 0.05], scattering_coefficients=[0.01, 0.01, 0.03, 0.05, 0.1, 0.1, 0.1])
plasterboard = ca.AcousticMaterial(name='plasterboard', absorption_coefficients=[0.15, 0.1, 0.06, 0.04, 0.04, 0.05, 0.05], scattering_coefficients=[0.01, 0.01, 0.03, 0.05, 0.2, 0.1, 0.1])
acoustic_plaster = ca.AcousticMaterial(name='acoustic_plaster', absorption_coefficients=[0.17, 0.36, 0.66, 0.65, 0.62, 0.68, 0.80], scattering_coefficients=0.2)
glass = ca.AcousticMaterial(name='glass', absorption_coefficients=[0.1, 0.07, 0.05, 0.03, 0.02, 0.02, 0.02], scattering_coefficients=0.05)
plywood = ca.AcousticMaterial(name='plywood', absorption_coefficients=[0.18, 0.12, 0.1, 0.09, 0.08, 0.07, 0.07], scattering_coefficients=[0.05, 0.3, 0.03, 0.5, 0.6, 0.7, 0.7])
########### read the room and the table from OBJ files, one acoustic object per OBJ group (Rhino layer)
room_obj_path = os.path.join(os.path.dirname(__file__), 'sample_room.obj')
room = ca.AcousticObject.from_obj(room_obj_path, materials={
'floor': concrete,
'plasterboard': plasterboard,
'glass': glass,
'ceiling': concrete,
}, name="sample_room")
# The table stands free in the room: an obstacle, reflecting from both sides
table_obj_path = os.path.join(os.path.dirname(__file__), 'sample_table.obj')
table = ca.AcousticObject.from_obj(table_obj_path, materials=plywood, name="sample_table")
ca.AcousticObject.assign_roles_by_group(table, {"wood": "obstacle"})
scene.add_acoustic_objects(room)
scene.add_acoustic_objects(table)
########### run a ray tracing simulation
rirs = scene.simulate(ca.Mono(ray_tracing=True, n_rays=10000, air_absorption=True))
########### analyze the RIR
analyser = ca.Analyser(next(iter(rirs.values())))
results = analyser.analyse()
########### print the results
analyser.print_table()
########## plot results
# analyser.plot_rir()
# analyser.plot_frequency_response(smooth=3)
analyser.plot('T30')
Output¶
125 250 500 1000 2000 4000 8000
----------------------------------------------------------------------
EDT 3.80 4.50 4.06 3.64 3.35 1.81 0.93
T20 4.53 5.73 4.10 4.22 3.72 2.06 1.11
T30 4.98 5.79 4.25 4.34 3.84 2.28 1.16
C50 -3.35 -4.66 -3.25 -3.92 -4.00 -0.15 3.66
C80 -2.72 -2.12 -2.03 -1.92 -2.10 2.33 6.07
D50 31.64 25.48 32.11 28.87 28.46 49.12 69.91
DRR -10.25 -9.09 -9.64 -11.26 -10.73 -8.03 -5.73
Ts 0.22 0.27 0.23 0.23 0.22 0.10 0.05
STI 0.40 0.36 0.40 0.39 0.39 0.53 0.67
G 27.09 28.28 29.03 30.32 29.62 27.19 25.30
SPL 127.09 128.28 129.03 130.32 129.62 127.19 125.30
LF nan nan nan nan nan nan nan
LFC nan nan nan nan nan nan nan