SoundMaker
Physics-Based Synthesis of Car Sounds
Kalpit V. Desai
[email protected]
Overview
• Synopsis
• Motivation
• Overall Approach
• Detailed Model
• Demo
Synopsis
• Synthesize sounds of a car
• Target application: Street-Crossing Simulator
other applications: Setting noise standards,
Games etc.
• Goal: to develop a parametric model based
entirely on principles of physics
• Use of signal processing concepts
• Why not use recorded sounds?
Motivation
• Recorded sounds
– Noise or extraneous inputs in recordings
– Inefficient for real-time control
– Limited applicability
• Parametric model
– Versatile:
change in value of parameter = a new car
– Efficient for use in real-time
Overall Approach
C/S
Area
Velocity
Wind
Engine+muffler
+
RPM
Weight
+
+
Acceleration
(throttle)
Tyres
Stereo
Doppler
Output
Detailed Model: Engine 4 strokes
Detailed Model: Engine (Cont)
RPM
Engine
One Cycle
Remove
Frequencies
>20K
Muffler
Output
Sounds
Model: Wind & Tyres
• Wind Friction
– Band Limited White Noise (negligible at very
low frequencies)
– Amplitude proportional to square of velocity
– Amplitude proportional to cross-section of
vehicle
• Tyres
– Band limited pink noise (HF prop. to velocity)
– Amplitude proportional to weight
Doppler Effect
Demo
(urr…sort of )
Future Plans (before GrandET demo)
• Solve the puzzle of muffler model
• Add Doppler effect
• Replace Matlab script with interactive GUI
Thank You!
Questions?