DENJIRO: This is an atlatl, an ancient hunting weapon that has reemerged in the modern era. Let me show you how to use it. The atlatl is used to throw long arrows like this one. It is said to have been used all around the world before the bow and arrow was popularized.
The atlatl helps to increase the distance and speed at which the arrow travels, and most importantly, it improves the accuracy of the arrow's trajectory. What makes it so accurate is the arrow's elasticity. When you watch this video in slow motion, you can see that the arrow vibrates as it shoots toward its target. The reason for this vibration lies in the trajectory at which the atlatl moves. With this LED light, you can see that the path of the atlatl moves up and down, which is then reflected in the trajectory of the arrow.
The more elastic the arrow is, the more it maintains its center of gravity and keeps the arrowhead stable.
Now, let's see what happens when we use a less elastic arrow. The arrow is not able to travel in a straight line. Let me explain this mechanism with this simple model. Let's pretend these balls represent an arrow's center of gravity. The spring represents an arrow with high elasticity, and the wooden stick represents an arrow with low elasticity. If I make the two vibrate simultaneously... you can see that the high elasticity ball does not move, but the low elasticity one does. With low elasticity, the center of gravity is not constant and the direction of the arrow changes.
Because the atlatl is a hunting weapon, it must be able to hit a target from many meters away. Since I cannot show this in the studio, I conducted this experiment outside beforehand. Let's watch the video.
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