Ex[heal]e was my senior design project for Biomedical Engineering. I, along with 3 other BME students worked with a professor in Emory to create an assistive breathing device for Chronic Obstructive Pulmonary Disease (COPD) patients.
The goal of the project was to find a way to help improve the breathing of COPD patients since they often face dyspnea, shortness of breath. In order to do so, we conducted a tremendous amount of research to identify solutions that already exist. We then identified the user needs by talking to patients, professors, and physicians. From there, we created the design inputs to create prototypes along with ensuring that our design did not infringe on any prior art. After finalizing on a design, we created a final functional prototype complete with the engineering analysis. We presented our device at a Capstone Design Expo attended by thousands of people.
My role in all of this was of Team Captain/Communicator.
I was involved in coordinating with advisors, organizing meetings with patients, ensuring that we always remembered the problem statement, creating designs, presentations, posters, and editing reports.
The goal of the project was to find a way to help improve the breathing of COPD patients since they often face dyspnea, shortness of breath. In order to do so, we conducted a tremendous amount of research to identify solutions that already exist. We then identified the user needs by talking to patients, professors, and physicians. From there, we created the design inputs to create prototypes along with ensuring that our design did not infringe on any prior art. After finalizing on a design, we created a final functional prototype complete with the engineering analysis. We presented our device at a Capstone Design Expo attended by thousands of people.
My role in all of this was of Team Captain/Communicator.
I was involved in coordinating with advisors, organizing meetings with patients, ensuring that we always remembered the problem statement, creating designs, presentations, posters, and editing reports.
USER NEEDS
The first step in tackling this problem statement was to identify our users and talk to them to obtain as much information as possible. To do this, I set up meetings with various physicians in Emory, Grady, etc. First, we went to the Veteran's Affairs (VA) hospital to talk to a pulmonologist, Dr. Ashish Mehta. He provided us with insight into COPD and the typical treatment courses. From there he referred us to pulmonary rehabilitation facilities to talk to actual COPD patients. I organized meetings with one of the facilities and went multiple times to talk to various patients. We had a questionnaire that would allow us to gain more information about the problems that patients face. From there, we created a user experience map and a user needs table.
DESIGN INPUTS
Once we had established the design inputs, we created functional analysis flowcharts, which led to the design inputs.
Design Parameters
PROTOYPES
Once the design parameters were identified, the next step involved conducting prior art research to learn more about the devices that already exist to combat this problem. Based off of this, we brainstormed and came up with many hand drawn sketches and 3D renderings of potential ideas.
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After creating multiple sketches and ideas, we narrowed them down to end up with 4 potential designs. To identify the pros and cons of each one, we created a design matrix to help us decide on a final design. The design matrix compared all of our concepts with the most important design criteria.
As can be seen from the table, Concept 4: Visual Feedback Device scored the most points. So we ensured that our device must include some sort of visual feedback device. During this time, a conversation I had with our design professor actually spurred the creation of a completely different design than the ones we had narrowed down. The design was a way to eliminate the electrical and software component of our previous protoype and utilize just physical methods. It involved having a detachable mouth valve and resistive breathing tube that users would blow into. This would cause a small ball in an upright, open tube to move upwards. This would allow the user to see how effective their breathing is by seeing how high the ball moves.
ENGINEERING ANALYSIS
After refining our design, we had to ensure that it was physiologically sound. We performed engineering analysis to ensure that our design was effective. To do this, we hooked up the device to a ventilator and measured the resistance offered by the device. Keeping the flow rate constant, we calculated how high the ball moves with varying ball masses. We then repeated this test for different flow rates. This way we could find out the optimal ball mass and height for the standard COPD patient. Using these numbers and obtaining feedback from a physician to determine average flow rates, we were able to identify the best range for the ball to be in. Demarcating the optimal range would allow users to visually see how hard they should blow the ball in order to maximize the reduction in shortness of breath.
One of the caveats of this is that COPD affects different people in different ways. It is hard to standardize a device to everyone's needs. This device is advantageous for various COPD patients since it can be customized for different patients. The weight of the ball, the resistance of the valve, and the optimal range can all be adjusted by using each patient as their own control.
One of the caveats of this is that COPD affects different people in different ways. It is hard to standardize a device to everyone's needs. This device is advantageous for various COPD patients since it can be customized for different patients. The weight of the ball, the resistance of the valve, and the optimal range can all be adjusted by using each patient as their own control.
FINAL DESIGN
We created a fully functional, physical prototype of the device using 3D printing. We printed all of the parts separately and assembled it together to fit perfectly. The 3D printed pieces were then sanded, polished, and painted to create an aesthetically pleasing device. The ball of correct mass was ordered and put into its place. Finally, the optimal range to keep the ball was marked using green paint.
I also created a poster for our design expo that would quickly and efficiently summarize the problem and our efforts.
I also created a poster for our design expo that would quickly and efficiently summarize the problem and our efforts.