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Instrumented Football Helmet. Development Team Joseph Jackson (ME) Adam McCauley (ECE) Shawn Kachnowski (ME) - Team Leader Matthew Wellner (ECE). Background Information. Since 1945, there has been at least one football fatality each year
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Instrumented Football Helmet Development Team Joseph Jackson (ME) Adam McCauley (ECE) Shawn Kachnowski (ME) - Team Leader Matthew Wellner (ECE)
Background Information • Since 1945, there has been at least one football fatality each year • In the NFL an average of about four concussions per weekend occur • 250,000 of the 1.5 million high school football players in the US will suffer a concussion per year
State of the Art • SIMBEX HITS System • Documentation published May 2005 • Current HITS System Helmet costs $2000 per helmet • Has been in development for two years and is currently being tested • Our goal was to create a simpler and cheaper product that will be available to a wider range of athletes
Importance of Development • Many less severe concussions often get overlooked because they do not cause significant short term damage • However, research has shown that athletes with a concussion history are more prone to future severe concussions • By knowing when less severe concussions occur, serious future concussions can be prevented • Having empirical data that confirms serious head trauma improves diagnosis accuracy
Objectives and Functional Requirements • Keep Costs Low (Double Cost of Helmet) • Read head acceleration with reasonable accuracy (±1 G) • Must be easily implemented into a current helmet model • Must work within given temperature range (0o – 150o F) • Must have a substantial battery life (3 hours minimum)
Other Functional Considerations • Amount of impact electronics must withstand (min: 80 G’s) • Comfort after Integration of Electronics • Device should be transparent to user • The electronics must be safely and securely held in place • Placement of Accelerometer • What position will produce the most accurate results
Design Process • Searched market for state of the art designs • Created a design on paper • Manufactured prototype design • Test and evaluate prototype
Major Components • Sensor: One three-axis accelerometer • 4 MHz PIC Microprocessor: Controls data collections • Output Writer/Standard Memory Card: Records data • Battery:Powers the circuit for the duration of one game • Linear Spring: Maintains accelerometer contact with head • End-User Software:Determines the severity of an injury or detects potential problems
Accelerometer Considerations • How many accelerometers? • Single • Multiple • Acceleration threshold
Challenges • Interfacing the various electronic components • Accuracy to cost ratio must remain reasonable • Packaging of the product into the helmet • Circuit must remain small enough to fit • Circuit must be robust • Use of software to read collected data
+9V 7805 +5V +5V LDI086V33 +3.3V Chip Select Serial Clk +V 20 2 3 4 A0 A1 A2 1KΩ 1KΩ 1KΩ Accelerometer Analog Voltage 1 2 3 4 5 6 7 CS DI GND 3.3V CLK GND DO PIC16F873A 2KΩ 2KΩ 2KΩ MMC 13 14 15 16 SCK SDI SDO 4MHz Data 8,19 18pF Circuit Design - Schematic
System Software - Microcontroller • Accepts three simultaneous analog inputs from the tri-axial accelerometer • Analog-to-Digital conversion • Forwards converted data to SD Card
System Software – End User • Individual player profiles • Possible to add player information such as height, weight and age • New stats can be loaded as they are obtained • Data bank can be separated into active or past players • Capable of reading filtered outputs to show major head accelerations
System Software Preview Player Statistics Window Graphical Concussion History Window Team Listing Window Data Management Window
Product Integration • Use of Styrofoam casing to protect accelerometer • Casing fits securely into the helmet • Spring is attached to accelerometer and outer shell
Product Integration (cont’d) • Printed circuit board is secure between inner and outer shells • Channels are cut in inner shell to allow for the running of wires • Memory card is accessible through spring loaded capability
Product Integration (cont’d) * all dimensions in mm
Prototype Costs • Accelerometer $31.25 • PIC Microcontroller $ 7.15 • Memory Card Connector $ 3.74 • Battery $ 9.00 • Memory Card (256MB) $29.50 • Helmet $65.00 • Implementation Materials $25.00 ~$175.00 • Cost of Parts (No Helmet) ~$110.00
Social and Ethical Impacts • Beneficial Outcomes • Use of this product can only help in the understanding of head injury • Safety of person is not compromised by the integration of this project • Reasonably priced to help provide usage for smaller organizations
Product Future • Integration into different helmet types • Possible wireless capability • Testing within helmet • Use of software to help interpret results
Conclusions • Built a programmable circuit • Circuit can read input acceleration • Circuit can output that data to memory card • Created computer software • Software can read memory card • Helps interpret data • Project needs more testing, but proves that a low cost model entirely possible
Thank You. Questions or Comments?