3 jaw gripper mate 1

[grunt58]

Im modeling a 3 jaw gripper and was wonder what mate to use to have all three jaws move together. I don't need the piston and linkage so I just have the body and the jaws. I have a limit mate on one jaw and I want to mate the other 2 jaws to the first one. So if any one of the 3 jaws is moved they all move. I tried a circular pattern but I can only move the seed jaw. The other 2 jaws wont move, they only move is the seed jaw is moved.

Thanks

Certified SolidWorks Associate
SW2009 X64 SP 1.0
Dell Precision T5400
Nvidia Quadro FX 5600
Xeon 2.5GHz Quad Core, 4GB RAM
XP Pro X64 SP2.0

 

[handleman]

Create planes that bisect the angle between the gripper fingers and use these planes for "symmetric" mates.

-handleman, CSWP (The new, easy test)

 

[grunt58]

I thought that was the way to go but could not think of how to do it. Im still not getting it to work right though. Mind explaining a little more or sending an example model? Im on SW 09.

Thanks

Certified SolidWorks Associate
SW2009 X64 SP 1.0
Dell Precision T5400
Nvidia Quadro FX 5600
Xeon 2.5GHz Quad Core, 4GB RAM
XP Pro X64 SP2.0

 

[CorBlimeyLimey]

Can you not just pattern the mated jaw?

 

[handleman]

SW10 here, so no model.

I assume the slots in the body where the jaws go have planes running through them? If not, you need them.

1. Mate each jaw so that it can move correctly in its slot. No limit mates yet, just positioned and able to move.

2. Create a symmetric mate between any corresponding faces/vertices/etc of Jaw 1 and Jaw 3, using the plane in Jaw 2's slot as the plane of symmetry.



-handleman, CSWP (The new, easy test)

 

[Updraft]

grunt58,

CBL has the simplest solution. A circular pattern works. I just made a simple assy of a single part constrained to two planes and circularly patterned about an axis native to the assy. I can drag any of the three instances and they all dynamically move in and out. If your circular pattern doesn't work then either you have other constraints locking things down or perhaps the axis/cylindrical surface you are using for the circular pattern is part of one of your parts.

- - -Updraft

 

[JMarv]

I can drag any of the three instances and they all dynamically move in and out.

For what it's worth, I've never seen that behavior. I've always seen the limitations that grunt58 noticed: ie. you can't dynamically move any of the patterned jaws, only the seed jaw. I've just learned to work with that limitation. Atached is the last 3-jaw gripper that I've played with.

Joe
SW Office 2008 SP5.0
P4 3.0Ghz 3GB
ATI FireGL X1

 

[Updraft]

Joe,

I just opened your file and with the limit mate it works as you describe, i.e., if you move the seed part the others move with it, however, the patterned jaws do not move if you grab them. With the limit mate suppressed you can move any of the jaws, but obviously they can move beyond the desired limitations.

- - -Updraft

 

[grunt58]

Joe that is exactly what I have done. It must be the limit mate that is interfering. As per updraft if you suppress the limit mate you can drag any one of the fingers and they all move dynamically.

Maybe its an previous version thing and SW10 you are able to drag patterns?

Got it to work per handleman.

Thanks all.



Certified SolidWorks Associate
SW2009 X64 SP 1.0
Dell Precision T5400
Nvidia Quadro FX 5600
Xeon 2.5GHz Quad Core, 4GB RAM
XP Pro X64 SP2.0

 

[handleman]

2010 works the same. The limit mate kills the ability to drag the seed components.

-handleman, CSWP (The new, easy test)

 

[Updraft]

How's this for strange. . .

I just created a top level assy, pulled in Joe's chuck subassy (fixed) and then set this subassy to be "flexible". In this top level assy I can drag any of the three jaws and they all move dynamically together within their limit (though the patterned jaws move opposite the direction they are being pulled). If I go back to the chuck assy itself I can only drag the seed jaw and move it within the limits. Very weird. I am running SWX2010, SP3.1

- - -Updraft

 

[CorBlimeyLimey]

Updraft ... That's a very interesting discovery.

grunt58 ... You should report this to your VAR. Not being able to move the jaws in the lower assy is now looking like a fixable bug ... or at least a fixable limitation.