Can you add a rack and pinion mate with constraints on your other mates?

paul_long

i'm trying to make a machine that mimics the flapping motion of bird. i'd love to be able to model and animate everything in onshape to get a feel for how it's going to look before i make it. i think i'm having two issues:

1) i can't get my initial location to be correct. that is what i want for the starting point:




and this is what i get:


i'm having a helluva time fiddling with the constraints because some of the constraints create errors for my other mates. 

for instance, a constraint on the revolute mate:



breaks everything:


has anyone had any sort of luck with a similar assembly?

best,
paul

owen_sparks

Hi Paul.

Don't think you need the gear and rack and pinion.

I'm pretty new to this so may be talking rubbish but if it were me:-

(1) Hide blue bits for now.
(2) Fix grey part.
(3) Start with pin mate for red bit, get limits and animation working.
(4) Unhide blue bits, Add Revolute mates for each of them.
(5) Add Rack and Pinion Mates (one for each blue bit) for the relationship between red and blue parts.  Add limits and use reverse direction if req'd.

If you can't get it working then if you could make the document (or a copy of the bits) public then I'm sure we would help.

Cheers,

Owen S.