Recording your jumps with a WOO is simple (almost too simple!??!). Pop the WOO on your board, put it in record mode, and you’re good to go! So what’s going on under the hood that lets a WOO measure your jumps?
It starts with Gravity.
The WOO is designed to take advantage of one wonderful universal truth about the earth: everything is being pulled to its surface by gravity. Gravity on earth is a constant acceleration - 9.8 m/s/s - and because of this, we can see exactly how fast something is accelerating towards or away from the earth's surface by measuring the vertical acceleration its experiencing over time.
To track acceleration over time, we use two sensors included in the WOO: an accelerometer and a gyroscope. The accelerometer gives us relative acceleration - how much force is being put on the WOO by your movement + gravity? The gyroscope gives us orientation: which direction is this acceleration coming from? By combining these two sensors, we can see exactly how much vertical acceleration you're experiencing!
For example, when something is in free-fall and experiences “weightlessness”, this means that it’s falling at exactly earth’s gravity and 0 vertical acceleration is being felt on-board. Alternatively, when something is shot into the air, the object is experiencing earth’s gravity PLUS the force of the acceleration upwards and a high vertical acceleration is experienced.
Integrating to find jump height.
Remember back in calculus & physics class how acceleration, speed, and position are related? If you track acceleration of an object over time, you can integrate that acceleration twice to determine change in position. That’s exactly what the WOO does, using the accelerometer to measure the values and the gyroscope to make sure your values are in the correct orientation.
The end product is a WOO that knows when you take off, how far you travel up and down on your jump, and can calculate the distance up and down to give you a jump height score. This is the WOO “Algorithm” in action!
What about horizontal accelerations?
One common question we get is: wouldn’t the WOO get confused by horizontal forces, like during a megaloop? Since the WOO is looking for only vertical acceleration using the accelerometer and gyroscope, the answer is no - the WOO sees this horizontal acceleration, but it does not use that data in determining jump height.
Have another question? Hit us up in the comments below!
Leo & Patrick