All Joints Static

Sythem · 7 May 2015, 17:44

Hello all,

I'm experienced using sketchup and wanted to make a complex hinge mechanism. So I've just installed the sketchyphysics plugin but I'm having a problem with the joint objects. I've scoured Google and these forums but don't see anyone else having this issue so I'm sorry if I missed one and this has been answered before.

Any joint I make behaves statically regardless of what state I use for it. That is, they will not move in the xyz axis and nothing attached to them responds to gravity.

My current model is just 3 "bars" hinged together. The two on the ends will spin about the hinge but the one in the middle is locked in place by two unmoving hinges. Any clue what I'm doing wrong?

Sketchup Make 15.3.330 32-bit & SketchyPhysics 3.5.6.

Thank you,
Sythem

Sythem · 7 May 2015, 19:42

Nevermind I figured it out.

For anyone else who didn't catch it at first looking at tutorials, after joining the hinge to the parts it needs to be grouped to one of the parts, then it will follow the motion of that part.

Anton_S · 7 May 2015, 23:14

All top level joints are static regardless of state you assign to them. A joint needs to have a parent group in order for it to be a movable joint.

protective1 · 23 Aug 2015, 21:18

@sythem said:

My current model is just 3 "bars" hinged together. The two on the ends will spin about the hinge but the one in the middle is locked in place by two unmoving hinges. Any clue what I'm doing wrong?

Sketchup Make 15.3.330 32-bit & SketchyPhysics 3.5.6.

Thank you,
Sythem

I tried creating 3 bars hinged together as you described in SketchyPhysics 3.6.0 and Sketchup Make 15.3.330. Did you encounter the same problem I did - that the outer bars can pass right through the middle bar (no collision detection)? Is collision detection broken for hinges? Unless I'm doing something wrong?

3 bars hinged together

Anton_S · 24 Aug 2015, 18:29

In order to make two connected bodies collide, you need to open SketchyPhysics UI, select the joint that connects two bodies, and in SP UI check the "ConnectedCollide" checkbox option. You have two hinges in your model. You'll have to check the "ConnectedCollide" for both hinges.