Objectives
Constraints
Protect the user from physiological and psychological damage produced by MRI noise
Mufflers attenuate MRI noise from ~110dB to at least 50dB.
Capture heartbeat sound to produce psychological comfort for patients to relieve stress
The deviation between heartbeats captured by the device under MRI (110dB) condition and real heartbeats should be less than 10 beats/min.
Does not interfere with MRI imaging
Device being 0% conductive material; 100% mechanical
Tolerate tiny movements of patient while maintaining the functionality.
Tolerate tiny movements of the patient while maintaining the functionality.
The chest piece should be able to collect the heartbeat within 6 cm from the sound source.
Minimize patient discomfort while ensuring the device’s functionality.
The muffler rim should be compressible with compressibility above 0.005 mm/g, less than 0.03 mm/g
Adaptable to children of varying ages, between 5-8 years of age
Chest piece position is adjustable within at least a 60 cm range.