Colbert Collision - Football Helmets and Concussions

thingiverse

This was the final project of two students in my physics class who were football players, which made this topic particularly relevant and interesting for them. They used a Vernier LabQuest to collect data from an analog accelerometer, and their results showed that a hit of just over 63 g's would be unlikely to cause a concussion. To start the project, I told students to assemble their sensor, attaching it to an Analog BTA Cable. The Black Wire goes to GND, the Orange Wire is +5V so goes to the VCC, and the Red Wire attaches to OUT. All you need to do is solder these three wires to the sensor and plug it into a LabQuest or LabPro. Since our accelerometer is an analog sensor we can read it easily with a Vernier LabQuest treating it as a voltage meter. Nerd Alert: If you need to know, basically we are using it as a voltage comparator. On the LabQuest (or LabPro) you need to identify your sensor. Select Voltage - Raw Voltage (0 – 5V). For our sensor, zero volts corresponds to -250 g’s, five volts with 250 g’s, and at 2.5 V we have zero g’s. In reality the 5 V wire gave me 5.2 V (the USB standard is 5 V but can be up to 5.25 V or as low as 4.4 V), so zero g’s was at 2.6 V and 250 g’s would be 5.2 V. Next, you'll need to set up "Data Collection" from the Experiment menu. In the "Collection" tab you'll want to dramatically increase the sampling rate. The first generation LabQuest lets you collect 100,000 samples/second. So that's what I recommend. I also decreased the duration to 0.2 s. The graph of the calculated column resulted in a graph of force vs. time. In the example graph below, the hit lasted for about 0.003 s and reached a peak of just over 63 g’s. Based on readings from the literature, a hit of this magnitude and duration would be unlikely to cause a concussion. With the growth of the Maker Movement there are now a lot of cheap sensors out there that can be interfaced in exactly the same way. Adafruit makes a 200g 3-axis accelerometer that looks promising, but you’d need 3 Vernier cables to read all thee axises simultaneously (also true with Vernier’s 3-Axis Accelerometer).