Multiple Limit Distance Constraints ( mechanical push/pull rods )

Hi there.

I dropped the bones armature world which I definitely don’t understand and that doesn’t look to be an easy fit for my mechanical rigging goal.

Empties, locked track constraint and limit distance looks to be the way to go, but I would need to set two distances for two different object to achieve desired result.

As you may know and as it has been diescribed before, it’s not really possible to add these two constraints in cascade, only the top one in the constraint outliner will work and the bottom one will be overiddent, given false mechanical movement ( example, pushrod assemblies with levers etc … )

Do you have a fix or another method ?


Frequently, people use IK to achieve that. Bones themselves don’t change length unless you tell them to, so a 2 bone IK chain will give you, in the middle, a position that maintains its distance from both the beginning and end of the chain.

For extremely complicated structures, it may be impossible (or just impractical) to limit them completely using constraints, and you might consider physics instead.