Constraining DOF of Bones in IK

[Rahul Girish]

Hi all,

I am quite new to Houdini so please excuse me if the answer is super simple.

Been trying to learn how to rig a little lately with small industrial robots (3DOF)
FK systems are simple enough to implement however, I want to create a simple 3 bone IK rig with each bone only given a single rotational axis of freedom. i.e. bone1 one can only rotate around x axis, bone2 - y axis, bone3 - z axis to reach a single goal. 
Is this possible? I hope this can lead me down the path to creating "simple" IK rigs for Industrial robots with 6DOF (but I am dreaming here).

I saw Maya already has a plugin for this sorta thing called Mimic, open source and quite elegantly done > https://www.mimicformaya.com/
I was wondering if its possible to build similar functionality within Houdini.

[Librarian]

Yes, it's possible ...Have fun ..search on GITHUB and google ..here you have something that peoples Done with Arduino just search
https://vimeo.com/175121779

 

Edited May 14, 2020 by Librarian

[Rahul Girish]

Hey Librarian,

Thanks for the link! I went through this walk through few days ago, along with almost 5-6 other rigging tutorials too. (Side FX have some great ones that explain a lot of fundamentals quite well through their rigging series of H16.)

However I cannot find the particular outcome or approach I am after. I think I clearly lack the terminology needed to explain my problem.
Simply put, I need bone1 to only move along x, bone2 to move only along y, bone3 along z. As soon as I have an IK system, it simply does not constrain the 'joints' to individual axis unless I use FK. Even with parenting or creating controller nulls in IK i cannot restrict movement to a single axis. I will attach some screenshots/gifs tomorrow to elaborate and explain myself better.

[Librarian]

@Rahul Girish  screenshots ?