The Arizona STEM Acceleration Project

BioFeedback Fusion

Engineering Smart Prosthetics with System Insight

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BioFeedback Fusion

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Engineering Smart Prosthetics with System Insight

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A 7th grade STEM lesson

Lacey Merritt

5/31/24

Notes for teachers

• The investigation and engineering project should be delivered in conjunction with learning about the different body systems or after systems have been introduced. Important to have understanding of of skeletal, muscular, nervous respiratory, and circulatory systems at minimum.
• There are 2 parts to this STEM Lesson:
• Investigating a Phenomenon: My oxygen level stays rather consistent even when I change up my activity.
• Engineering prosthetic with biofeedback
• Creating sensors to measure pressure points and flexibility is optional. It is a nice way to get a sensor to meet specific needs but Vernier and Pasco sensors can work as well.
• Lesson can be separated or done together as presented. If time is limited, engineering portion can become a long-term project that is given shorter amounts of time throughout entire unit.
• Technology: Build tools to collect digital data meaningful to the prosthetic. (optional)
• I do not, but many like to put a monetary value to engineering projects. I open up to found/recycle objects to add to prototype.

List of Materials

Part 1 - per Investigation Groups (2-4 students)

• pulse-ox reader
• Computers or tablets
• Graph paper or digital graphing tools
• Scientific notebooks

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Part 2 - per Engineering Team (2-3 students)

• Velcro strips for each team
• sponge
• 3x cardboard tubes
• 3x PVC pipes
• twine
• duct tape
• thin pool noodle

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per Engineering Team (sensor making optional)

• Velostat (or substitution)
• Conductive fabric
• Bread Kit (Raspberry pi, Arduino)
• electrical wire
• gator clips

Standards

7.L1U1.11 Construct an explanation for how organisms maintain internal stability and evaluate the effect of the external factors on organisms’ internal stability.

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U1: Scientists explain phenomena using evidence obtained from observations and or scientific investigations. Evidence may lead to developing models and or theories to make sense of phenomena. As new evidence is discovered, models and theories can be revised

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U2: The knowledge produced by science is used in engineering and technologies to solve problems and/or create products.

Standards

Mathematics:

7.RP.A.3 - Use proportional relationships to solve multistep ratio and percent problems..

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Engineering:

Standard 2.1-8 Create engineering solutions by applying a structured problem-solving/decision making process

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Standard 3 Apply mathematical laws and principles relevant to engineering technology.

3.2 Use data collection and analysis to display data and verify its accuracy

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Standard 4 Apply scientific laws and principles relevant to engineering technology. Analyze relevant properties of materials used in engineering projects.

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Standard 5 Apply technology and tools to engineering solutions. 5.2 Use measurement devices such as calipers, oscilloscopes, and digital multimeters to gather data for analysis.

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Technology:

Standard 4. Innovative Designer - Students use a variety of technologies within a design process to identify and solve problems by creating new, useful or imaginative solutions.

Objectives:

• Describe how various body systems (e.g., respiratory, circulatory) work together to maintain homeostasis.
• Explain how positive and negative feedback loops depends on many factors and status fluctuates.
• Understand how these interactions can be measured and analyzed through physiological indicators like heart rate and oxygen levels.
• Construct an explanation for how body systems operate to support the functioning of an organism.
• Model how the body responds to various internal and external stimuli to maintain homeostasis.
• Analyze data to determine the effectiveness of feedback systems and prosthetic designs.
• Utilize (develop) measurement devices (SPO monitor, digital multimeters and flex/pressure sensors) to gather data for analysis.
• Apply interdisciplinary learning to solve complex problems involving human body systems and biomedical technology.

Part 1 Investigation Agenda (90-100 minutes)

Part 2 Engineering Agenda (90-180 minutes)

Intro/Driving Question/Opening

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What conclusions can we draw about the body's ability to maintain homeostasis during and after physical activity based on our data?

How can we design an experiment to test the effects of [breathing techniques, activity level…] on oxygen levels and heart rate?

What are the implications of deviations from normal oxygen levels and heart rate during exercise on health and performance?

How can we interpret pulse oximeter data to identify potential issues with a prosthetic device, such as poor fit or restricted blood flow?

What are the broader implications of integrating pulse oximeter feedback in prosthetic engineering on improving patient outcomes and advancing the field of biomedical engineering?

Introducing the Phenomenon

• Explore freely with the device to and make observations. Notice any patterns? Is there potential cause and effect relationships?
• Narrow in on an observable phenomenon: pulse-oxygen monitor shows a change in heart rate can vary greatly but the oxygen % tends to stay virtually the same.
• Model initial thinking
• Develop testable questions
• Each group should have access to the following:
• pulse-ox device
• chromebook/

tablet

• notebook
• color pencils

Notebooking: An Assessment Tool

Notebooks are a working document. The notebook begins as a basic diagram/model of observation and grows more detailed and new understandings are uncovered.

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It is important to have students make sense of their observations and make clarifications/corrections as they deepen their understanding. It is essential to have open dialogue amongst students in whole group as much as small group.

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Make a point to come to a consensus and address/ challenges misconceptions.

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Part 1

Investigate Interacting Systems

• Use notebook to record and sketch observations throughout the investigation and project.

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• In this portion of the investigation, students will plan and conduct an experiment. Allowing student groups to select independent variable can provide interesting results/ discussions. ( examples- activity level, stress, resting position…)

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• Remind students identify what they will be measuring and what must remain constant.

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• Support systematically collecting and recording data during these investigations.

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• Students can calculate the percentage change in heart rate and oxygen saturation from one measured task to the other. Graph the data and identify trends.

Part 1

Investigate Interacting Systems

• Use notebook to record and sketch observations throughout the investigation and project.

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• In this portion of the investigation, students will plan and conduct an experiment. Allowing student groups to select independent variable can provide interesting results/ discussions. ( examples- activity level, stress, …)

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• Remind students identify what they will be measuring and what must remain constant. Support systematically collecting and recording data during these investigations.

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• Identify patterns and cause-and-effect relationships

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• Ask students: What patterns do you see emerging? What are cause-and-effect relationships between different conditions?

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• Model initial thinking and sensemaking session

Part 1

Obtain Information & Communicate Understanding

• Students will manipulate a number of given body systems to maintain a healthy allow students to manipulate the scenarios. Note any patterns between Body Control Simulation and hands-on observations. How does the simulation model compare to the hands-on investigation? Any limitations?

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• View the informative video. Through this video, students will have the scientific terms to explain what they have observed.

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• Further evidence through text. Article through Khan Academy and CK-12

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• Create a detailed model to explain the phenomenon and make visible the seemingly abstract concept of feedback loops in context of today’s investigation. Use vocabulary terms to label concepts.

Assessment

Part 1

Investigate Interacting Systems

• Students develop a model to how heart rate and oxygen saturation change in response to different activities and stressors and how the body works to stabilize these parameters.

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• Students construct an explanation for the causes of the change in cell and how it impacts stability.

Part 2 Engineering Agenda (90-180 minutes)

Notes for teachers

• Engineering prosthetic with biofeedback
• Creating sensors to measure pressure points and flexibility is optional. It is a nice way to get a sensor to meet specific needs but Vernier and Pasco sensors can work as well.
• If time is limited, engineering portion can become a long-term project that is given shorter amounts of time throughout entire unit.
• Technology: Build tools to collect digital data meaningful to the prosthetic. (optional)
• I do not, but many like to put a monetary value to engineering projects. I open up to found/recycle objects to add to prototype.

List of Materials

per Class:

Glue gun station

Cutting station (manned by teacher)

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per Engineering Team (2-3 students)

• left shoe (student choice)
• 24’ Velcro strip for each team
• sponge or thin pool noodle
• 3x cardboard tubes
• 3x PVC pipes
• twine
• duct tape
• pulse-ox reader
• Computers or tablets
• Graph paper or digital graphing tools
• Scientific notebooks

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per Engineering Team (sensor making optional)

• Velostat (or substitution)
• Conductive fabric
• Bread Kit (Raspberry pi, Arduino)
• electrical wire
• gator clips

Part 2

Engineering Solution

• Set up notebook or make copies of engineering design packet for each student.
• Introduce the problem: need for prosthetic of a former student. (See notes below for more information
• What is biomedical engineering?
• Review (or introduce) engineering design process
• Parameters and constraints
• Must be able to able to walk a minimum of 10 meters unsupported.
• Use designate materials
• Research and brainstorm possible designs.
• Draft prototype base on best solution. Take measurements off of the student in the group that will be testing the prosthetic. Designs must include measurements and materials.
• Build prototype

Part 2

Engineering Solution

• Test prototype taking notes and data as you go.
• ensure the length of the prototype does not create a discrepancy
• the biofeedback results do not show excessive stress (Heart rate/ SPO% stays consistent)
• flex and/or pressure sensors show equal pressure to ensure hotspots and blisters do not develop.
• Record results and alterations.

Part 2

Engineering Solution

• Test prototype taking notes and data as you go.
• ensure the length of the prototype does not create a discrepancy
• the biofeedback results do not show excessive stress (Heart rate/ SPO% stays consistent)
• flex and/or pressure sensors show equal pressure to ensure hotspots and blisters do not develop. Make sensors to collect authentic data.
• Record results and alterations.

Part 2

Engineering Solution

• Make revisions and improvements to prototype based on data and biofeedback
• Showcase in class gallery. Take note of similarities and differences and difference in design. What patterns do you see? How did the data support the design?
• Communicate your final result and reflections.

Differentiation

• Do frequent check ins with struggling students (performance, behaviors)

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• Provide additional support on design options, or limit choices if too overwhelmed

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• chunk in smaller tasks and check off as completed

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Remediation

Extension/Enrichment

• Alternative Problem: Although her below the knee prosthetic leg could get wet, the cleaning process was very time-consuming, and a specialized prosthetic for bathing purposes was costly and not covered through insurance. https://www.designboom.com/design/lytra-prosthetic-leg-helps-amputees-shower-safely-04-19-2022/
• Video the test using the sensors and create an educational play by play of how the structure is a solution to the problem.
• Create a prosthetic from 3D printer design for animal. Currently found a post on Facebook that sought support for bengal kitty, Belle. We will be doing this this fall.