Optimized Acoustic Phantom Design for Characterizing Body Sound Sensors

Area of Science:

• Biomedical Engineering
• Acoustics
• Medical Device Characterization

Background:

• Devices for capturing body sounds (e.g., lung, heart) are vital for health monitoring.
• Acoustic phantoms are used for repeatable device testing, mimicking skin coupling.
• Lack of standardized phantom designs hinders device comparison and characterization.

Purpose of the Study:

• To investigate how acoustic phantom design elements impact acoustical characteristics.
• To compare frequency responses of various phantom constructions.
• To identify an optimal acoustic phantom design for consistent device measurements.

Main Methods:

• Employed a design of experiments approach to compare phantom constructions.
• Evaluated phantoms with different driver types (loudspeaker vs. sound exciter) and support structures (gelatin/grid vs. plate).
• Assessed device measurement consistency on optimal versus non-optimal phantoms under varying conditions (weight, position).

Main Results:

• An acoustic phantom using a loudspeaker and a gelatin layer on a grid exhibited a flatter, more uniform frequency response.
• This optimal phantom design outperformed other constructions, including those with sound exciters and plate supports.
• Devices measured on the optimal phantom showed more consistent results across different weights and positions compared to a non-optimal phantom.

Conclusions:

• Acoustic phantom design significantly influences the acoustical characteristics and device measurement reliability.
• A loudspeaker-driven gelatin phantom offers a superior design for accurate characterization of body sound devices.
• Statistical models provide insights for optimizing phantom design, leading to improved medical device characterization.