Mechanical rigging where two levers control one bar

Wooow, first post in 6 years o.o

I’m using blender to make an animation of a solidworks piece, which over there worked thanks to various… constraints?
Like in this video: [FIXED LINK]

However I can’t manage to rig the second bar so that it moves with two levers (…nor make the levers move with the bar).

Simplifying the problem: red is fixed, and blue,green should “follow” purple guy (and no, “copy rotation” won’t solve it)

Any ideas on how I should go around this? :slight_smile:

In other words, the bar ( has two hinges attached to the arms… I know there’s the Rigid Body constraint which has hinges, but AFAIK it can’t be animated by me, only by gravity/other objects during simulation.
Whereas I want to make an animation of it moving and picking up stuff…

I wanted to distract me with some rigging problems but your video is unreadable. 156 octets, whichever way I try to get it. No can play. And your schematics aren’t very clear. Show us what can move or rotate with arrows and the hinge points. Please, use some flashy green or red. (Yeah, I know I’m demanding… but making things clear helps those who can help.)

My apologies, thought it was understandable… (img1) (img2)

purple(and black copies) (img1) bar should be moved by the two handles, rotating along the axis (img2). The arms connect the handles to the bar.

Fixed video link in first post.

I’d use two bone chains, one consisting just of the lefthand (lower) lever and its attached arm, the other of the righthand (upper) lever, the upper arm, two segments for the bar and the hand.

The first (upper) segment of the bar has an IK constraint of chain length 2 targeting the lower arm.

Rotating the two levers around the Y-axis now works as expected. The bone for the lower bar is not actually needed; if you delete it everything works the same way.

Best wishes,


compoundLever.blend (550 KB)

that is perfect :open_mouth:
thanks a lot, I had completely skipped over IK thinking it couldn’t do such things!!

btw, here’s the result