Why do quaternion have a positive 360º followed by a negative 360º

Need Help Circuits
1

Quaternions loop from 0 to 1 to 0 within 360º then continue in that order in the negatives. They loop in that order.

I want to know how quaternions can have 2 different ranges for 360º

2

Quaternions are intriguing and can be difficult to understand. They are used to represent rotations in three-dimensional space and possess unique properties compared to other methods, such as Euler angles.

3

I appreciate your comment, but it doesn’t answer my question. Do you need me to clarify anything.

4

yes please

5

With quaternions, each axis can rotate 360 while positive. Then it does another 360 in the negatives. It will loop back to the start afterwards.

6

Are you trying to fix the problem In Rec room or RRS?

7

There isn’t a problem I’m just asking a question about quaternions as a whole.

8

I’m not totally the best with quaternions yet but I’m getting there.

Generally quaternions are a four dimensional representation of orientation in a 3 dimensional space, and it’s use is to solve gimbal lock caused by euler rotations. Hence why there are 4 dimensions, x,y,z,w.

I think the reason you’re experiencing this with your quaternions is because of the “up vector’s” direction.

Take the rest of this explanation with a grain of salt, but if you break down your quaternion into it’s forward and up vectors, while the forward vector is rotating about the world axis, the up vector is isolated. And depending if the up vector is positive or negative will result in your rotation being in the positive range or negative range.

I believe this is where it solves the issue with gimbal lock where rotations may suddenly “snap” from 0-360, as instead quaternions move smoothly from it’s min to maximum rotation.

If you have a quaternion output that is doing this kind of behavior, you can break it down into it’s up and forward vectors to really see what’s going on.
You can do this by using 2 “rotate vector” chips and the following vectors:
0,1,0 as the up vector. The amount the quaternion “rolls” on the axis.
1,0,0 as the forward. The axis of the quaternion / orientation.

The result of these will show you how your quaternion is rotating, and might help better represent what’s going on under the hood of the x,y,z,w dimensions.

Hope that helps!

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9

Thank you
I’m kind of slow and I have been struggling to figure out quaternions for a while now.
I’ll try this out.