Creating a conditional animation based on geometrical properties of a rigid body

[samuele_bolotta]

Hey all! I'm working on a project with mocap data (c3d). My goal is to create a rigid body between two markers so that, if the rigid body reaches a certain angle (aka < 0°), some sort of animation gets triggered (so as to let the user visualize that the condition occurred). I've been trying to look for resources about this, but could not find any. Any insights?

[Hikaru_T · Accepted solution]

The HUD (Heads-Up Display) feature comes to mind for visualizing the condition. As for triggering an animation, the Animation Trigger" feature could be useful. However, I am not sure how to use these functions or how to control the HUD depending on the circumstances.

One approach I have tested involves using a Relation Constraint. In my setup, the color of the material of a cube changes when the rotation of Hips rigid body around the y-axis becomes less than 0 degrees. This constraint worked as follows:

 

 

I hope these ideas can provide some direction for your project. 

Best,