Linear Coupler Mate 1

[steris]

Hi All,

I have a model with a vertically sliding door and a counterweight. The door is mated to its guides to constrain it in the horizontal plane and it's vertical sliding motion is min/max limit distance mate from one of the stops. The counterweight is also constrained in the horizontal plane by its guides. For the vertical constraint, I moved the counterweight to its "door closed" position and then moved the door to its "door closed" position. Then I created a linear coupler relationship between the door and counterweight. This works great until I close and reopen the assembly. When I re-open, the door is closed but the counterweight is in an arbitrary vertical location. The linear coupler mate is active from that arbitrary position thereby making the counterweight's movement wildly incorrect. Clearly I am not using the linear coupler relationship correctly but I don't know what to do. Any thoughts?

Thanks!
Steris

 

[SnowCrash]

Rebuild ( ^Q ) ?

--
Hardie "Crashj" Johnson
SW 2011 SP 2.0
HP Pavillion Elite HPE
W7 Pro, Nvidia Quaddro FX580

 

[steris]

Rebuild doesn't help. I think the problem is that SW doesn't save the relative location of components - it just rebuilds and solves the mates on opening. Since there is nothing to locate the counterweight in the vertical plane, it just gets thrown in and the coupler mate is activated from it's starting location. Unfortunately, I don't know how to solve this issue.

 

[EEnd]

I recently tried experimented with the linear coupler mate and gave up on it for this very reason. Instead I added an extra part made up of reference geometry which accomplished what I desired as a mechanism.

For your motion: Create an new part with a plane 45 degrees from one of the primary planes. Insert that part into your assembly with a coincident mate between the slanted plane of the new part and the origin of the assembly. Then add mates between the new part and the door so that the new part moves sideways with the door. The mate between the slanted part and the assembly origin should cause the new part to move up and down as the door moves side to side. Once that works the counterweight can be attached to the new part.

Eric

 

[maxh3]

Just a wild guess here, when you open the assembly are the parts truly in random positions, or are they in their default positions?

When you go to the advanced mates and click on the distance mate, the first text box right there is for the default distance value. After clicking that, the max and min boxes become active below. Maybe if you set the default for the door at the minimum value and that of the counterweight at max (or vice versa) it'll work?