Unbreak My Heart

Unbreak My Heart

Student Design Packet

Create Design
often for a device / Try to make a design based on your prior knowledge or experiences For example, use clay to stop a pipe from leaking.
Evaluate Design
How well does it work? / Determine how well your design will work, and then test it. How much water comes out of the pipe when you use your design? How long will it last?
Generate Reasons
Brainstorm possibilities / Think about reasons why your design did or did not work. Brainstorm all the possible reasons for why you thought your design did or did not work. Perhaps it doesn’t stick well to the pipe, or it is too porous to create a good seal.
Generalize Results
What does your data tell you?? / Determine whether the patterns that you noticed from the data you collected can be summarized to make a general statement about your ideas. What do the numbers “say”? How do your measurements describe the success of your project?

Notes Page

Answer questions from the PowerPoint presentation

1. Think of three words that begin with the prefix “bio.”

______

2. What do you think “bio” means?

______

3. What do you think the words “engineer” and “engineering” mean?

______

______

4. Based on your answers, what do you think an “engineered biomaterial” is?

5. Brainstorm a list of possible problems and solutions you think engineers may have to design products for.

Problems / Solutions

Case Study:

A Pencil in His Heart

What happened to Nathan King on his 12th birthday could be classified as a parent's worst nightmare. Bursting with energy, Nathan bounced a football off the wall of his room, dove onto his bed to retrieve it and somehow drove a No. 2 pencil through his chest and right into his heart. "I kind of felt it go in," he says, "but it didn't hurt, so I looked down. Then I started yelling, 'Mom! Mom! Mom, I'm gonna die!'"

Without his level-headed mom, he might have died. Many parents would have instinctively tried to pull the wooden pencil from Nathan's chest. But Lorri Earley, a trained nurse, saw the pencil throbbing rhythmically in her son's chest and knew where it had probably lodged. She knew that pulling it out could unleash a torrent of red that would bleed the boy dry in a matter of minutes. "There was no way we'd touch it," she told TIME.

So while Lorri dialed 911, she kept one hand cupped over the pink rubber eraser to prevent the panicky Nathan from yanking it. "There was nothing you could do," recalls Nathan's stepfather. "Adrenaline all the way up to your eyeballs, and all you can do is hold his hand, let him know you're there."

A CAT scan at a local hospital confirmed Lorri's battlefield diagnosis. Not only had the pencil pierced Nathan's heart, but it had penetrated a valve. ______

Discuss in class

§  What is the damage that needs to be repaired in this case study?

·  What is a possible solution that could help to resolve the medical problem you identified?

Create Design: Brainstorm

As a team or pair, examine the case study and brainstorm a list of possible solutions in solving Nathan’s problem. Encourage everyone to share their ideas freely. Do not criticize others’ suggestions. By the end of the class, you will need to determine the solution you would like to design.

NEEDS: In solving your problem, what are possible situations that your solution will need to solve? (Example Responses)
Immediate Problems: 1. It needs to be safely removed without causing excessive bleeding. 2. We need to calm the patient
Short Term Problems: 1. Infection caused by pencil 2. Broken pieces of pencil in the body 3. Blood could be leaking into the pericardium 3. Pericardium could fill with blood and stop the heart from beating.
Long Term Problems: 1. Compromised (weakened) wall of the heart 2. scar tissue build-up that would stop blood flow
NEW IDEAS: Create a list of possible solutions that might meet your needs. Explore as many ideas as you can. These ideas can include existing or new products.
Immediate: 1. Need something to stop the bleeding, like a large band-aid: something that soaks and stops the flow of blood 2. Drugs can calm the patient
Short Term: 1. Antibiotics to stop infection 2. a camera to view inside for pieces of pencil, a tool to go inside the heart without disturbing the pericardium 3. A tool or clamp that can block any fluid flow into the pericardium.
Long Term: 1. Follow up MRIs to view any damage to tissue 2. a way to periodically remove scar tissue in the heart
OUR DECISION: Explain the need your team will meet and the new idea you have for a system that will meet that need. Explain why this is the best option.
To safely remove the pencil without causing excessive bleeding, we will design an instrument that blocks the flow of blood into the pericardium.

Our team’s choice for a possible solution is:

(name of your team’s product)

Create Design: Illustration

Each person in the group or pair will sketch a design. Afterwards, share your ideas with your partner(s). Label each part of the design that you think is essential for making your design function, and list out the materials that you will need to make it all happen.

Materials: (Example Responses)
-  1 lime (to represent heart)
-  1 balloon with water (to represent pericardium)
-  1 staple gun
-  3 pH strips (1 to measure pH in pericardium before stabbing, 1 to measure pH in pericardium after stabbing, and 1 to measure pH in pericardium after staples are placed and pencil is removed)
Illustration: (Example Response)

Create Design: Systems

Engineers use diagrams and models to help them think about systems. Diagrams and models are convenient ways to describe how a system works.

In the previous task, you identified essential parts of your design. Use the system diagram below to define the parts that are necessary for your system to work. Add more boxes as needed. Be prepared to share your ideas with the class.

Name of Solution
Accept all reasonable answers
Subsystem
Something to prevent blood from flowing out of the heart when the pencil is removed

DEFINITION

Subsystem is an essential part of a system that accomplishes one goal.

Create Design: Systems and Function

With your design team, write the name of each subsystem (essential part) in your design. Write a description of the specific function for each subsystem. Make sure that each subsystem has only one function. You should think carefully about each function because the more you clarify the goal of each subsystem, the better your design will be.

Subsystem Name / Function
(Example Responses)
staples / (Example Responses)
To seal off the pericardium from blood influx
Suture / To stitch together heart muscle after the pencil is removed
Suture: pericardium / To stitch together the pericardium after the pencil is removed

Create Design: Requirements

Now that you have thought about each subsystem and its function for your bio-solution, you should figure out what features are necessary for you design to work.

Each of your subsystems has requirements. There are two types of requirements. Must-have requirements are necessary for your design to work. Nice-to-have requirements are not necessary for you design to work, but they make it more attractive.

DEFINITIONS

Must-Have Requirements are features that are necessary for a design to work.

Nice-To-Have Requirements are unnecessary features that make the design more attractive.

Record your ideas about the requirements for your design. Decide which of these requirements are must-have and which are nice-to-have.

Requirements (Example Responses) / Must-Have / Nice-to-Have
Staples that are sterilized to prevent infection / X
Tongs to hold the heart in place during stapling / X
A staple machine that staples around the pencil in one push / X
Sutures to sew together the heart immediately / X
Anti-infection drugs to prevent inflammation / X
Anti-coagulant drugs to prevent blood from clotting around staples / X
Camera to view inside the heart to find pencil pieces. / X

Create Design: Revise It

Now that you have thought about functions and requirements, sketch your revised design in the space below. Include as much detail as possible so that others can understand how your design will work.

At this point, students should make sure to include all “need-to-have” requirements.

Below are some ideas you should discuss as a team. Be prepared to address these ideas during your presentations.

Explain your need for this design and the design’s requirements.

Use your sketch to describe how the design will function.

Describe what other information you will need to understand as you construct your design.

Evaluate Design

In order to test your model, determine how you will measure its success.

For example, how will you measure:

1. How well blood is prevented from entering the pericardium?

2. How well you prevented blood flow from the heart?

3. How well you repaired the torn heart tissue?

4. How well you calmed the patient?

(Your answers will vary, depending on your design.) (Example Response)

We will measure the pH of the pericardium before the stabbing, after the
stabbing, and after the staples are put in place. This will determine how much
lime juice (blood) has seeped into the pericardium (balloon).

Build your model and test it!

Fill in a diagram. Make sure to do three trials. (Example Data Table)

pH Level in pericardium model

Trials / 1 / 2 / 3
Before Pencil Stabbing
After Pencil Stabbing
After staples are put in place
After pencil is removed

Generate Reasons

Think about reasons why your design did or did not work. Brainstorm all the possible reasons for why you thought your design did or did not work.

Generalize Results

Determine whether the patterns that you noticed from the data you collected can be summarized to make a general statement about your model. What do the numbers tell you? How do your measurements describe the success of your design?