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Assembly Constraints, Sweeping between limits.

Assembly Constraints, Sweeping between limits.

Assembly Constraints, Sweeping between limits.

(OP)
Hello All, I did a bit of searching and am looking of the best way to sweep a mechanism between limits. In the past, using mating conditions, I'd often 'vary constraints' to show the sweep of something. (Is this still available in NX7.5?..couldn't find it.) Now, I usually just know the angle of the stops, and vary an expression between the angles ends (several key-ins). Or sometimes I use multiple constraints suppressing those that are not needed to show the positions. However, I want to vary an angle by sweeping (much like in vary constraints) between it's mechanical limits using the dynamic handles, or by having arrangements cycle through a range. What is the best way to accomplish this?

Regards, and have a Great Weekend!

KLINE

RE: Assembly Constraints, Sweeping between limits.

Have you looked at Assembly Sequencing?  If you're just looking to have parts of an Assembly be in either one position or another, have you looked at Arrangements?

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
http://www.siemens.com/plm
http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.
 

RE: Assembly Constraints, Sweeping between limits.

(OP)
I currently use arrangements, but smooth sweeping is what I am after, and it sounds like sequencing can do it? I have not looked into Sequencing...I will right now. Please add any tips.

Thanks John,
KLINE

RE: Assembly Constraints, Sweeping between limits.

(OP)
I lied, I have used assembly sequencing before....for just that 'showing an assembly sequence'. That still is for if I know exactly what I want to show. Often I find in reviews that I must show a smooth sweep, back up a bit...talk about something in this position then back up more or go a little forwards etc. If I could dynamically move a mechanism having stop at the stops, I would be set. Do you think either arrangements or sequencing can do this? If so, please give me a couple tips or point me to a thread.

Thanks,
KLINE

RE: Assembly Constraints, Sweeping between limits.

(OP)
One more, along with affecting only certain components (leaving some out, pulling others back in while in review)...this seems hard with sequencing. I suppose only showing certain sequences could be enough though...so I'll leave this alone unless someone comes up with an idea for dynamically moving a mechanism with stops that stop the dynamic movement.

Regards,
KLINE

RE: Assembly Constraints, Sweeping between limits.

Once you have a Sequence defined, you can either let it run to completion or you can step it one step at a time, forward or backward.  It still sounds like this would give you what you want.

An alternative would be to use Move Component, but in that case you may need to suppress any constraints which define the exact position of something.  In your example of a part which can rotate, as long as there is nothing preventing (constraining) the part from rotating, you could just go to Move Component, select the component/sub-assembly you wish to rotate, set the Transform Motion type to 'Dynamic' and then just use the drag handle to move it.  or you could pick an explicit motion type, such as 'Rotate', where you define the axis and type in an angle.

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
http://www.siemens.com/plm
http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.
 

RE: Assembly Constraints, Sweeping between limits.

(OP)
Thanks John.
KLINE

RE: Assembly Constraints, Sweeping between limits.

In sequencing you can just put some object 'in the way' and turn-on collision detection and ask that it stop when it 'runs into something'.  You don't have to change the sequence, if it interferes with something it will stop.  If the interfering object is removed it won't stop.  If the interfering object is moved, it will simply stop at a different point in the sequence.

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
http://www.siemens.com/plm
http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.
 

RE: Assembly Constraints, Sweeping between limits.

(OP)
Back at this...any more ideas from you John, or anyone else?

I tried going the sequence route, but I am missing something or it will not work for me. I have multiple components with different stops. In other words, one component stops but the next one needs to keep going until it stops (collides), but they share a common part that is actuating them. (It seems as if I will need redundant components to do hide shows with different assembly constraints as assembly constraints can not be manipulated once in sequencing...?)

Thanks for all your help,
KLINE

RE: Assembly Constraints, Sweeping between limits.

If it's this complex you may have to turn to full-blown Motion Analysis (i.e., Kinematics) to get the motion that you're looking for.

BTW, even if you do not yet own the Motion Simulation module you can still review the Help files which might help you determine whether this will better address your needs and if it looks promising you might be able to convince your Siemens PLM rep to get you a trial license.

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
http://www.siemens.com/plm
http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.
 

RE: Assembly Constraints, Sweeping between limits.

(OP)
Thanks John, I was able to get sequencing to show what I need by using fixed redundant components. I put motions in to move components to their stops. Once stopped, I swap them (via disassemble and assemble) for a fixed redundant component in the stopped position. (I'm still somewhat disappointed in that I can't simply show these things dynamically relying on complex constraints...but that is no doubt in a future release.)

I'll look into a trial of kinematics.

Thanks again for your help,

KLINE

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