Temperature Measuring Device for a Football Helmet

1
Temperature Measuring Device for a Football
Helmet

• Design Team Matthew Harris
• Katherine Davis
• Clients Kenneth Wood, M.D.
• Robert W. Harrington, M.D.
• Advisor Wally Block

2
Overview

• Problem Statement
• Product Requirements
• Location for sensory unit
• Types of sensory units
• Experimental Data
• Possible Circuitry
• Conclusion
• Questions

3
Problem Statement

• Develop a temperature measuring device that
  measures the ambient temperature inside a
  football helmet during physical activity.
• Gain insight on heat stroke
• Future prevention of heat stroke

4
Product Requirements

• Record temperature between 20 to 70 degrees
  Celsius
• Withstand jolts produced from heavy impacts
• Fit securely inside helmet
• Unaffected by fluids
• No contact with players skin
• Exposed to circulating air within helmet
• Small Size

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Alternative Locations

• Location 1 In Circular Pad
• Adequate air flow
• Major thermal center
• Exposed circuitry
• Limited space

• Location 2 Upper front
• Large amount of space
• Protected by padding
• Difficult to surface mount
• Major sweat zone

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Final Location Second layer rear padding

• Advantages
• Adequate air flow
• Removable
• Sensory unit protected
• No contact with player
• Plastic sheet supports circuitry
• Disadvantages
• Pads may contact sensory unit
• Major sweat zone

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Alternative Thermistors

• Disc Chip Thermistor
• High Resistance
• Small time coefficient
• Not protected against fluids
• Material could irritate player
• Glass Encapsulated Thermistor
• Very sensitive
• Withstand sever environments
• More room needed in circuit
• Could shatter

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Epoxy Coated Chip Thermistor

• Advantages
• Protected from fluids
• Large Resistance
• Small Time Coefficient
• Very Durable
• Will not harm player
• Disadvantages
• Not as sensitive as glass encapsulated
  thermistor

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Experiment
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Possible Circuit

• Output is frequency
• Different temperatures have different frequencies
• Able to transmit with FM converter
• Speaker could be attached

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Conclusion

• Best Location- second Layer of back padding
• Best Thermistor- Epoxy Chip Thermistor

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Questions?