Hello,
does anyone know what the “Motor Target Position” inside the in Cone Twist Constraint actually means and how it works?
The documentation [www.sidefx.com] doesn’t really clarify it for me, and when I tried adjusting its values or changing my setup, I couldn’t see any noticeable difference in the results — the object itself or motor's rotation axes didn’t seem to be affected in any way.
I also haven’t been able to find any example scenes that make use of it.
If anyone has insight, I’d love to hear it.


Background:
What I’m really trying to build is something like a wheel with suspension that only moves along a single axis, and that led me to this attribute.
A bit of a side note, but although the official Car Rig SOP makes use of the Translation Limits property, when I try to apply it to achieve a bouncy motion strictly along a single axis, it doesn’t seem to allow for it—even if I tweak the Range or Stiffness—and it still tends to drift into the other axes.

So if I want to completely lock the motion outside of one axis, do I basically need to combine it with a slider constraint or use condir/condof?
The problem is that a slider makes it tricky to softly constrain to a single point along the axis, while condir/condof forces me to set it up for every other constraint, which I’d like to avoid if possible.

Sorry for the long background, but if anyone has advice on this as well, I’d really appreciate it.

The motor target position is clamped to be within the allowed translation range, so you'd need to have a non-zero translation range along at least one axis for there to be any noticeable effect (similarly, the target rotation for the motor should be within the cone rotation limits)
Depending on your setup, you might also need a higher Target Position Stiffness too to see a more noticeable effect

@cwhite
Thank you for the advice! This was really helpful.
As you mentioned, I didn’t notice the relationship with the translation limits.

I also think I now understand the concept: it’s not the actual “Motor” (the rotation anchor) that translates, but the constraint itself.
And the Motor is like just a additional soft constraint goals setting for position & rotation, rather than actual "Motor".
This is exactly what I was looking for! (as I mentioned in the background).

Now I can tightly constrain its position along a single axis (by increasing the stiffness of the Translation Limit),
while keeping its position with a bouncy effect (by lowering the damping of the Motor Position),
all within a single constraint relationship.

Thanks again for sharing your knowledge!