Instrumented Football Helmet Louis Criso (ECE) Francis Kitrick (ECE) Ryan Lewis (ME) Robert Sorbello (ECE)

Problem Statement Design a working football helmet that can analyze the force of impact and determine if the impact is dangerous to the player. Design a working football helmet that can analyze the force of impact and determine if the impact is dangerous to the player. A microprocessor in the helmet will store data regarding the impact for analysis that can be later uploaded to a computer. A microprocessor in the helmet will store data regarding the impact for analysis that can be later uploaded to a computer.

Motivation According to the National Football League, there are 160 concussions sustained every year. According to the National Football League, there are 160 concussions sustained every year. Roughly 17% of all high school football players in the U.S. will suffer a concussion each year. Roughly 17% of all high school football players in the U.S. will suffer a concussion each year. If left untreated, a concussion can be detrimental to a players long-term health. If left untreated, a concussion can be detrimental to a players long-term health.

Approach Equip a standard football helmet with pressure sensors and accelerometers to measure and store the impact force sustained. Equip a standard football helmet with pressure sensors and accelerometers to measure and store the impact force sustained. Build a testing apparatus to properly test and calibrate our design to prepare it for game situations. Build a testing apparatus to properly test and calibrate our design to prepare it for game situations.

The Schematic Processor Processor MMC MMC Accelerometers Accelerometers Flex Sensors Flex Sensors Battery Battery Voltage Regulators Voltage Regulators

The Printed Circuit Board (PCB)

ARMexpress LITE Features 32K Flash memory 32K Flash memory 6 A/D channels, 10bit resolution, 100kHz sample rate 6 A/D channels, 10bit resolution, 100kHz sample rate SPI support with 600 Kb transfer rate SPI support with 600 Kb transfer rate

Memory Map

A/D Channels 6 A/D Channels 6 A/D Channels 15 KHz sampling rate 15 KHz sampling rate 6*15 KHz = 90K of data for one second 6*15 KHz = 90K of data for one second So we would need 9K of space to record hits for 100 ms (1/10 th of a second) So we would need 9K of space to record hits for 100 ms (1/10 th of a second) The A/D channels will be consistently buffered through the flash memory until a certain threshold is reached. The A/D channels will be consistently buffered through the flash memory until a certain threshold is reached. Once this threshold is reached by any one of the sensors, then the next 100 ms will recorded to the flash memory and written to the memory card. Once this threshold is reached by any one of the sensors, then the next 100 ms will recorded to the flash memory and written to the memory card.

Programming Logic Overall software design of helmet includes: Overall software design of helmet includes: Clock divider Clock divider Obtaining inputs from sensors Obtaining inputs from sensors Determine intensity of recorded data Determine intensity of recorded data Output accordingly Output accordingly

First step: setting the sampling rate ARM processor runs at 60mhz. We want to scale this down to 15khz. ARM processor runs at 60mhz. We want to scale this down to 15khz. First step in software is to create a delay function/clock divider. First step in software is to create a delay function/clock divider. Using intervals obtained through clock divider, store input from sensors into variables/memory. Using intervals obtained through clock divider, store input from sensors into variables/memory.

Next: using the data Data from all sensors are stored in assigned spots according to the type of sensor it was obtained from. (accelerometer or pressure) Data from all sensors are stored in assigned spots according to the type of sensor it was obtained from. (accelerometer or pressure) Values from sensors are compared against calculated threshold values corresponding to intensity of hit to the helmet. Values from sensors are compared against calculated threshold values corresponding to intensity of hit to the helmet.

The Output If the recorded hit is “safe” ie. below the threshold value, value is discarded from memory. If the recorded hit is “safe” ie. below the threshold value, value is discarded from memory. If the hit is determined “un-safe” ie. Stronger than allowable for the player’s safety then that incident is recorded by saving the values of the hit onto the card memory. If the hit is determined “un-safe” ie. Stronger than allowable for the player’s safety then that incident is recorded by saving the values of the hit onto the card memory. Finally alarm (led, buzzer) is triggered. Finally alarm (led, buzzer) is triggered.

Apparatus Design Simple pendulum Simple pendulum Use design specifications from existing patent for football helmet testing (US 6,871,525 B2). 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. 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) 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. After the information from the sensors and accelerometers is gathered, the data needs to be analyzed to determine threshold. The Gadd Severity Index (GSI): The Gadd Severity Index (GSI): Pass/fail basis: over 1,000 is a fail. Pass/fail basis: over 1,000 is a fail.

End Deliverables Plan on delivery a working football helmet that can measure the force of impact, determine if the impact was of danger to the player, and store this data to be analyzed later. Plan on delivery a working football helmet that can measure the force of impact, determine if the impact was of danger to the player, and store this data to be analyzed later. A working testing apparatus to test future football helmet designs. A working testing apparatus to test future football helmet designs.

Budget ItemBudget Accelerometer$31.25 Wireless Adaptor$70.00 PIC Microprocessor$10.00 Li-Ion Battery and Manager$10.00 Building Material$30.00 Testing Material$50.00 $201.25

Questions? Comments?