Design a Heart Valve

Design a Heart Valve Model Part 1: Research heart structure, blood flow, heart valve mechanics, valve tissue autonomy

The challenge for this project, directly from Mr. Tronconi's website is: "You are a team of engineers for a bio-materials company that has a cardiovascular systems client who wants you to develop a model that can be used to test the properties of heart valves without using real specimens." 

This end goal was broken down into individual parts. In this part, we brainstormed ideas and took stock of any basic knowledge about the heart our group already had. We then learned a lot about the function of the heart and its components. This included reading information about the heart along with drawing sketches of the human heart.

Shown below along with the sketch of a human heart are the Young's Modulus practice problems. These equations are used to determine the elasticity of a material which we used to determine which materials to use in our heart valve.

Design a Heart Valve Model Part 3: Material Testing, Design and Prototype Building/Testing/Re-design/Re-building

This was final part of the project; and the most difficult.  First, we chose materials we thought we might want to use for the model, and designed and ran an experiment to test find the Young's Modulus of our chosen materials. We wanted to use the most elastic materials that could bend but not break under the pressure we would be putting it under.

Next, we had to build the model of the heart. We connected tubes to a glove by cutting off a finger of the glove and where the hand enters. This glove was our heart, and we could squeeze it to apply pressure and force the water (blood) through the tube. To make the valve, we first pushed an elastic material through the tube and it would take a good amount of pressure for the water to get past it. This was supposed to stop water from pushing backward after getting through and causing a leak. Then, we superglued 2 fast food drink cups and a gatorade cap to the end of the tube. The water would have enough pressure to break through the lids and cap when the "heart" was "pumping", but it wasn't strong enough to push through when the heart was idle. This was successful in preventing backflow and allowing water through the valve.

Located on our lab write up is pictures and a more in depth analysis of our valve.

Reflection:

One thing I think I did well was communication since lab reports are entirely about communication and synthesis of information. I think my group also collaborated well on this project. We used a strategy of divide and conquer, as one person did the Young's Modulus, another tested materials, and other brainstormed which worked well within our limited time frame.

One thing I think I need to improve on is critical thinking. The Young's Modulus was very hard to do and I got frusturated when I didn't understand the concepts. Also designing the heart valve was very tedious and there were points were I wanted to give up.