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Comment by thehappypm | Hacker News Reader

Can you explain gimbal lock? I can’t wrap my head around it

A physical analogy is an azimuth-elevation mounted antenna tracking an object that flies over the zenith. When the object is near the horizon, the angular velocity of the azimuth actuator may be near zero and the elevation actuator may be small. Near zenith, the angular velocity of the elevation actuator may be small and the azimuth actuator may be near infinity.

ELI10?

The main thing is how when representing the 3D looking orientation as multiple angles (pitch=up/down, yaw=compass direction), you lose control over the yaw axis when looking straight up.

Of course gimbal lock is a thing, and there are ways to avoid it, even without quaternions, but I'm curious as to when it should be avoided. I think that gamers are now so used to it, that removing it might cause more problems than it solves

I guess that's more for airplane simulators then. But I'd also think any physics engine where things can rotate arbitrarily need to work correctly here.

I also think, despite various sources on the internet saying "quaternions are the solution to gimbal lock", that classical 3D vectors and 3D matrices without quaternions also perfectly solve it.

Agreed absolutely. I've used quaternions when someone else made the decision that was what the physics engine was going to do! But when I'm the decision maker it's 3d vectors and matrices all the way

Why?

> I can’t wrap my head around it

Pun intended?

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