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Designing a system to detect head injuries during football games, integrating electrical, computer, and mechanical engineering aspects.
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Instrumented Football Helmet Louis Criso (ECE) Francis Kitrick (ECE) Ryan Lewis (ME) Robert Sorbello (ECE)
Problem Statement • Design a system to detect head injuries during football games. • Project involves aspects of electrical, computer, and mechanical engineering. • Each team member worked on a specific aspect of the project
Motivation • There are 160 concussions sustained in the NFL every year. • Roughly 17% of all high school football players in the U.S. will suffer a concussion each year. • Untreated concussions can be detrimental to a player’s long-term health.
Presentation Objectives Circuit Board Design – Robert Sorbello Processor Coding – Louis Criso Data Interpretation Software – Francis Kitrick Mechanical Testing – Ryan Lewis
ARMexpress LITE Memory Carda Flex Sensors + Accelerometers Battery Matlab Software Approach • Integrate flex sensors and accelerometers into helmet. • Store data on memory card • Graph data with Matlab software
The Schematic • Processor • MMC • Accelerometers • Flex Sensors • Battery • Voltage Regulators
ARMexpress LITE Features • 32K Flash memory • 6 A/D channels, 100kHz sample rate • SPI support with 600 Kb transfer rate
Memory Map Local array is located from hex values 7C00 to 8000. (1K) Flash memory is available from roughly 5000 to 7C00. (~11K)
A/D Channels • 6 A/D Channels • Chosen sampling rate: 340 Hz • 6*340 Hz = 2040 bytes of data for one second • 1020 bytes of space needed to record hits for 500 ms. • A/D channels are consistently sampled until threshold is reached. • Once threshold is reached by any one of the sensors, then the next 500 ms will be stored in a local 1 kilobyte array and subsequently recorded to the memory card.
Software Analysis • Data is saved as it is streamed from the processor. • Output file as read by software is a long array of integer values.
Software Analysis • Data from all sensors are stored in assigned spots according to the type of sensor it was obtained from. (accelerometer or flex) • To do this the program picks out the corresponding data values for each individual sensor. • This is possible because we know the processor output from the hardware coding.
Displaying Results • Data values from each sensor are plotted vs time to show impacts over the course of game play. • Spikes in plot are “concussion-possible” impacts.
Results • Sample data plotting.
Meaning of Results • Values from sensors are compared against prior known threshold values corresponding to intensity of hit to the helmet. • Calculations obtained from mechanical testing apparatus/test dummy.
Mechanical Tasks Completed • Head Impact Research • Researched current studies on concussion prevention and testing • Apparatus Design & Construction • Used existing design for inspiration of apparatus • Apparatus Analysis • Completed dynamic analysis of apparatus
Apparatus Design • Simple pendulum • Use design specifications from existing patent for football helmet testing (US 6,871,525 B2). • 2 m long arm with a 19 kg impactor, generating 280 J of energy. • With this information from patent generated MathCAD file to solve for initial angle (75 degrees)
Post Impact Analysis • After the information from the sensors and accelerometers is gathered, the data needs to be analyzed to determine threshold. • The Gadd Severity Index (GSI): • Pass/fail basis: over 1,000 is a fail.
Tasks To Be Completed • Integrate the components into the helmet. • Sensor Calibration • Test the final design. • Implement our design into a real event?
Cost of Production Our Total: $276.25 Industry Total: $446.25 *Our cost was lower due to the Villanova Football team providing us with a used helmet.
Conclusion Recommendations: Wireless transmission of the data in real time. Battery life gauge Increasing overall memory Direct USB connection Questions?