Point of Measurement

Our goal is to detect jumps, and measure their height. But how is this "jump height" measured? - The only sensible answer to this question is from the base. This is clearly emphasised by the definition of height as well as common practice in sport competitions like the high jump.

Aside from scientific and historic considerations, measuring from your board on water level is also the only "common sense" solution: Suppose your friend goes for a huge jump, he takes off the water, goes up in the air, then time freezes. You just see a static image of your friend up in the air, at the apex of his jump. If tasked to measure height, where would you start your measurement from? Would you ever even consider measuring jump height from the chest or wrist of the rider on the water? Wouldn’t you naturally measure from sea level (aka the surface of the water, where the board left the water) upwards? We think this one is pretty straightforward.

The next question is concerned with how well the data gained from placing a sensor on the board assists us in our goal to measure jump height. To accurately measure jump height, there is two main data sources we are looking for: acceleration data and orientation data.

Through both data points, a jump can be easily detected for its distinct movements. In acceleration data for example, there is a clear signal difference between the noise created when riding on the water vs. gliding through the air. For orientation, one can measure the ronounced, and always characteristic pop motion.

Tip: Jump detection accuracy can easily be validated by the airtime. Simply stop the jump time off a video and compare to the jump duration given.

The clear answer is no, because they measure different things. Just by mounting position alone. Take the measurement of an inverted frontroll as an example: If we were to allow different mounting positions, this image is the result we'd be seeing. A board-mounted sensor will go overhead, measuring the jump at 8 meters. Meanwhile, the chest-mounted sensor might only measures 6 meters. Both are measuring correctly, they simply do not experience the same motion. This means that two people doing exactly the same trick will get difference height scores depending on what way of measuring they use. Not a fair game.

You do not want to allow for people to gain an advantage or disadvantage depending on their measurement-method. The same trick should be scored the same way. Thus, your position of measurement has to be unified.

As teased, the clear conclusion is that the by and large best position to measure a kiteboarding jump is on the board (and always on the board).

It is the only common sense measurement position, ensures comparable scores and provides the best takeoff and landing detection. The resulting precision can be seen above. Thanks for reading, we hope you learned something!

Here's a screenshot of the current 36.7 meter World Record jump by Hugo Wigglesworth taken from one of our analysis tools. What you see is the height jump graph, including the uninterrupted upwards motion as well as the slowed downwards accelerations, implying the use of heliloops.

Top left, you can also spot a WOO Sensor representing the live board motion throughout the jump. As you can tell from the chosen frame, Hugo's board was lifted upside down at the apex of the jump - a clear case of Woosting! This is actually very impressive, given the immense forces acting on his body at that point.

This is just one example of the valuable data we gain from measuring on the board. It's a great tool to remotely validate jumps. One, that gives us the confidence needed to run operations like the biggest kite competition in the world.