Key components of the stethoscope prototype. Credit: Will Kirk/homewoodphoto.jhu.edu
Even in outer space…the beat goes on!
The heart beat that is. But how best to monitor its condition on lengthy space treks, say to Mars?
An engineering team of students has designed a new stethoscope for NASA to deliver accurate heart- and body-sounds to medics who are trying to appraise astronauts’ health on long missions in the less-than-quiet environment of a spacecraft.
Consider the number of whirring fans, humming computers and buzzing instruments within a spacecraft. That ambient noise contaminates the stethoscope signal.
The new device uses both electronic and mechanical strategies to help the stethoscope’s internal microphone pick up sounds that are clear and discernible – not only within a noisy spacecraft but even when the device is not centered correctly on an astronaut’s body.
Microphone technology
A team of students at The Johns Hopkins University’s Whiting School of Engineering — under the guidance of James West, a Johns Hopkins research professor in electrical and computer engineering – came up with the new approach.
West is co-inventor of the “electrets” microphone technology developed for telephones and used today in almost 90 percent of the more than 2 billion microphones produced each year.
The stethoscope project was developed during a two-semester mechanical engineering senior design course offered by the university’s Whiting School of Engineering.
They were given a small budget to design and build a prototype requested by a sponsoring business or organization.
Performance-enhancing improvements
The device also includes many other performance-enhancing improvements, including low power consumption, rechargeable batteries, mechanical exclusion of ambient noise and a suction cup – so that it sticks firmly onto the patient’s chest.
The team that came up with the new device: Elyse Edwards, a senior from Issaquah, Wash. Along with fellow seniors, Noah Dennis of New York City, and Shin Shin Cheng of Sibu, Sarawak, Malaysia.
According to Dennis: “Considering that during long space missions, there is a pretty good chance an actual doctor won’t be on board, we thought it was important that the stethoscope did its job well…even when an amateur was the one using it.”
Earthly uses
While the stethoscope was developed for NASA’s use, this improved medical gear could also be put to use here on Earth.
Scenarios for its use could be in combat situations, where ambient noise is abundant, and also in developing countries where medical care conditions are less than ideal.
Professor West also plans to use the device to record infants’ heart and lung sounds in developing countries as part of a project that will attempt to develop a stethoscope that knows how to identify the typical wheezing and crackling breath sounds associated with common diseases. This would allow on-site medics to help make preliminary automated diagnoses.
By Leonard David via Phil Sneiderman/The Johns Hopkins University