Velocity Vector for camera tracking in physics simulation

Support Animation and Rigging
1

Title says it all as sticky requests we make our titles specific.

All in Cycles Render (if that makes any difference)
I Have a sphere which is rigid body dynamic sitting on a twisting pathway made up of rigid body static planes (Representing a Rube Goldberg machine)

I’m trying to get the camera to follow the ball and rotation that the ball is moving but I’ve noticed there is no velocity vector (or i can’t find it?)

If not this then is there a way to make camera point towards the ball but 10 keyframes ahead? That is take properties of an object 10 keyframes from the given keyframe the properties are being applied to?

I’m still new to blender and greatly appreciate any advice.

2

Moved from “Basics & Interface” to “Animation and Rigging”

If I read your post correctly, I’d say you need to put a Track To constraint on the camera, using your sphere as the target.

3

Track-to doesn’t not work for my purposes. The camera floats above the sphere as it rolls (emulating a roller coaster ride). Track to would work WONDERS if I could find a way to track objects in future keyframes (otherwise the camera is just going to look straight downwards and not rotate with roller coaster ride.)

4

I’m not sure I understand the need for seeing future frames.

So you want the camera to move with the sphere, but look ahead of it and rotate with it, but not spin around it (like running around the surface of a tire)? Essentially, you want the effect of a follow-behind or first-person POV from the camera. Is that about right?

The cheat way to do it (my personal favorite way of working) would be to have a curve that follows the path of your track… then set the camera with a Follow Path constraint. From there, you can hand-animate the camera’s location on the path to match the speed variations in your rigid body sim.

A more general rig is tougher to pull off because there’s no guarantee which axis your sphere will rotate about, but you want the camera to remain parallel to your track. Raw parenting won’t work because the camera will spin all kinds of crazy ways. Copy Location would get the camera to follow the sphere, but it won’t rotate with any twists in the track. I’m spitballing here, but you might be able to some kind of funky rig where still have a curve that follows your track and an Empty that has both a Path constraint and a Copy Location constraint on your sphere… then maybe your camera is a child of that Empty. Not sure… would need to experiment with that one.

Personally… I prefer cheating :slight_smile: