Does My Model Valve Stack up to the Real Thing?
Building a model enables study with no need for live tissue.Copyright (left) 2004 Microsoft Corporation, One Microsoft Way, Redmond, WA 98052-6399 USA. All rights reserved. (right) 2012 Robertolyra, Wikimedia Commons
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Following the steps of the iterative engineering design process, student teams use what they learned in the previous lessons and activity in this unit to research and choose materials for their model heart valves and test those materials to compare their properties to known properties of real heart valve tissues. Once testing is complete, they choose final materials and design and construct prototype valve models, then test them and evaluate their data. Based on their evaluations, students consider how they might redesign their models for improvement and then change some aspect of their models and retest—aiming to design optimal heart valve models as solutions to the unit's overarching design challenge. They conclude by presenting for client review, in both verbal and written portfolio/report formats, summaries and descriptions of their final products with supporting data.
When engineers are presented with challenges to develop new technologies or products, they follow the steps of the cyclical engineering design process. After learning as much about a project as possible, they choose the best materials, and proceed to prototype and test the best design solution. Biomedical engineers research to find (and sometimes create new) materials that are suitable to fabricate artificial replacement heart valves. The ideal materials have similar properties and behavior to real heart valve tissues. They use these materials to develop valve designs that mimic the function of real valves.
During this activity, like biomedical engineers, students research and test potential materials that mimic the qualities of heart valve tissue. They collect quantitative evidence to determine if any of the materials are appropriate for artificial valve designs. Then they choose the best materials to design, construct, test, improve and present final aortic valve models for client review.
After this activity, students should be able to:
- Work through the steps of the engineering design process to examine a problem, research it and decide the best way to tackle it, design and create a solution, test the prototype solution and redesign as needed, and then report their findings.
- Research the materials that have been used in artificial heart valves in the past; identify possible materials for their prototype valve model designs.
- Test materials to determine their elasticities; compare those values to the elasticity of real heart valves.
- Construct prototype model heart valves, collect data from testing the model for its functionality compared to a real structure, and use the data to analyze success of the model.
- Compile, summarize and present their research and designs to the class in verbal and written formats.