3
$\begingroup$

I want to rig a small mechanical interaction between two pieces of metal. In theory it's simple: the upper leaver should get pushed up by the lower one (which is already driven) and then drop down - while always keeping contact.

Example using keyframes

However, due to the large contact area and odd shape of the elements I cant make this work using the regular constraints. What is the right way to rig such an interaction?

$\endgroup$
4
  • 2
    $\begingroup$ Do you want to get the reasonably convincing appearance as in the video above ... or something more complicated to simulate any two shaped levers? Physics simulation? $\endgroup$ – atomicbezierslinger Nov 21 '20 at 3:36
  • $\begingroup$ you could completely fake the rotation of the right one with some shapekeys, but as atomicbezier says, it all depends on what you're trying to achieve, are you trying to simulate physics? $\endgroup$ – moonboots Nov 21 '20 at 8:39
  • $\begingroup$ The whole thing is part of a single mechanism which will be re-used in 8 different places. The speed of the bottom lever isn't constant, and the upper one needs to stay in place if the lower one points down and amplify its motion at the tip if it gets pushed up. Since its always the same interaction im trying to avoid physics, but the important part is that it looks good and the lever is in the right position. $\endgroup$ – Ismir Egal Nov 21 '20 at 15:14
  • 1
    $\begingroup$ Can I make the following assumptions about the surface where two levers meet? The lower lever has a convex plane and the upper lever does a flat one. $\endgroup$ – tetii Nov 23 '20 at 14:51
3
$\begingroup$

A rigging method without physics

enter image description here


To simplify this report, consider only two-dimensional space. It is also assumed that the lower lever has a smooth convex curve and the upper lever is a straight line on the side where the two levers touch. With this assumption, rigging with Armature was able to solve the problem.

First, for simplicity, coincides the coordinate system of the lower lever object with the Armature space. In other words, only the upper lever slides on the fixed lower lever in the Armature space. This behavior could be realized by using Follow Path and IK constraints. Then, the behavior of bones was transferred to the both lever objects. Finally, the rotating shaft of the upper lever was fixed by using a Copy Rotation constraint.


Armature

enter image description here

enter image description here

enter image description here


Mesh Objects

enter image description here

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.