Controller [WIP] Quaternion based PID controller

Have you ever run into the problem of wanting to control the rotation of a physics based actor with the same elegance that PID controllers offer you for the translation axis?

Well I have found a quaternion based algorithm for a PID control and implemented it. I am working on finalizing a package and you will be able to access it on the Unity asset store soon.

Demo: http://media.wcsaga.net/keldorkatarn/quaterniondemo/

Tell me if you think this is an interesting script you would like to see.

 

Yes please!

 

Second that

 

I already submitted it as a draft for the asset store.

 

You beauty!

 

Here you go https://www.assetstore.unity3d.com/#!/content/40096

 

If the target is constantly moving, does it work well?

 

Depends on what you want to achieve. If you just want the object to keep matching the target's rotation, then yes that doesn't matter. If you talk about perfect target tracking like for example to aim a gun at something, that's a bit tricky but can be done. I'm still looking into the prefect way of achieving target tracking since that's also what I'm going to use this for. Once I find the perfect way to do that I'll add a tutorial video to its asset store page. My current approach is to pre-calculate the "look at rotation" by precalculating the target position a number of frames into the future, to compensate for the lag. But there are numeric solutions to compensate for this kind of lag in PID controllers, I just need to figure out how to do it for this specific problem. That's a general problem to be solved when using a PID controller however, it's not specific to this one, it'd be a problem for linear movement too.
But I'm definitely interested in that as well, so I'll keep you updated on that.

 

If you don't mind, I'd like to learn more about the algorithm itself. I'd like to try and implement it myself, if I can. Can you point me to where you found the algorithm, a white paper or something? It would be a great learning exercise for me, and I'd like to develop my own implementation to use in a character controller asset I'd like to release.

Any assistance would be massively appreciated!

Edit: Is this the paper?
http://ltu.diva-portal.org/smash/get/diva2:1010947/FULLTEXT01.pdf

Any update on figuring this out, btw?

 

It's actually this paper: https://arc.aiaa.org/doi/10.2514/6.2012-5028
And no sorry no further progress, I have been busy with other projects in the mean time. I'm sure I'll come back to this eventually but it'll be a while. Right now I'm working more on the UI side of things.

That paper actually goes way further than what I did. The Quaternion controller is basically the groundwork they put down before moving on to what they actually want to do

 

Thanks for the info! This will be very helpful. Yeah menus are a whole art of their own. Maybe you can add some PID animations to them

Good luck with your projects!

 

Thank you. I'm working on something with the Noesis guys