"Flexible" sub-assemblies

It's probably best to explain this request with a hypothetical case:-

I model a pneumatic cylinder as 3 parts (piston, cylinder, clevis each end)
and make an assembly out of them with mates that allow the piston to move in
the cyliinder and the clevises to pivot.

I model a door assembly comprising a frame, door and hinges.

I create a top-level assembly and add the 2 subassys. I want to add an
angular mate to define the position of the door, and I want the pneumatic
cylinder (which opens/closes the door) to adjust to the correct length with
the clevises at the correct angles, corresponding to the defined door angle.

Is this possible without dissolving the sub-assys into the top level assy?
I'm on SW2004.

TIA,
John Harland

 

I am quite sure you can in 2004. Try this: Make sure that the
assemblies in your top-level assembly are set as "Flexible". Right
click the assembly in the tree, select Component Properties and mark
the radio tab for Solve As ( if it isn't already) as "Flexible". The
alternate is "Rigid".

Add your mates and the angle of the door will determine the position of
the cylinder and piston based on the mates definied in your subassys.

Bull

 

Thanks Bull, I'll give that a try.
I'd tried right-clicking on the sub-assy, but hadn't thought to look in
Component Properties.

Cheers,
John Harland

 

One thing to keep in mind, If both cylinders open and close the same,
this will work just fine. But if you want each cylinder to operate
differently, (i.e. one open and the other closed) you will have to
create identical configurations, each subassembly will have to be a
different config.

Mike

 

I just had this situation with some swivel casters I needed to rotate.
I brought in the casters, mated them and then changed them to flexible
so they would swivel. After changing them to flexible some of the mates
changed to a suppressed state and the caster mounts moved on the panel.
I double checked the status of the mates, and some were suppressed. You
may want to check this when they are resolved or suppressed in each
configuration.

For your situation, you might also try an advanced angle mate, with a
range of motion for the door hinges, and drive the door with the
cylinder, as this would be what it seems you are simulating.

peace, Diego

 

In many situations that is what I would do, but there are times when a piece
of machinery is set to rotate to a number of specific angular positions, and
the position of the actuator is immaterial.

Cheers,
John Harland

 

Does that mean that if you change the piston position from the top level
assembly, and then open the sub-assembly on its own, the position of the
piston will have changed?

John

 

Yes, depentant on which config is active. Being the subassemblies in
an assembly are no more than a reference, you are in fact changing the
the subassembly, for a specific config, in the context of the main
assembly. This also holds true for parts. Based on the example, one
config would be 'open' and the other 'closed'.

Mike