Medical Scanner Noise Dampening

2022-PLET, 22-V-HM

The objective of this project is to research and test a material which will be used in an MRI and CT scanning machine to reduce and dampen noise caused by high frequency vibrations. On top of this, another objective was to develop an alternate testing method for SKF to test for damping characteristics of polymeric materials.

 

Team Members

Scott Borman | Justin McClafferty | | |

Project Poster

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Project Summary

 

Overview

MRI and CT scanning machines have become a vital part of the medical industry. However, these machines often emit high frequencies vibrations which cause large levels of noise which can make patients feel uncomfortable and increase anxiety. SKF is looking for a way to reduce this noise level by incorporating a method of damping into the bearings of these machines.

Objectives

  • Research and test a polymeric material to be used as a high vibrational frequency isolation mount within the MRI and CT scanning machines
  • Perform testing with the dynamic mechanical analyzer with time-temperature superposition to prove a tan δ value greater than 0.12 for frequencies up to 3,000 Hz
  • Design and develop a vibro-acoustic testing methodology to prove damping capabilities of polymeric material through decibel transmission loss, amplitude changes, phase shifts, and acoustic attenuation
  • Develop a method for tan δ comparison between the two testing methods for validation

Approach

  • Background theory and research of material damping characteristics and testing allowed for the choosing of a neoprene elastomer as the candidate material
  • Research proved that DMA with applied TTSP would allow for tan δ analysis for a frequency range well beyond the require 3,000 Hz
  • CAD models and drawings developed for the vibro-acoustic testing fixture and was machined in house at Penn State Behrend
  • Materials testing and results analysis performed in the PLET laboratory

Outcomes

• Results indicate a 60A durometer neoprene will be sufficient to provide the damping properties needed by SKF to reduce noise levels within the MRI and CT scanning machines
• The vibro-acoustic testing method is a new way to test for damping capabilities of materials; allows for decibel transmission loss, acoustic attenuation, phase shifts, amplitude changes, and tan δ to be measured
• After further optimization and improvements to the vibro-acoustic method, SKF will have a more cost effective and efficient way to measure damping and sound energy dissipation properties other than DMA