collision in Wildfire..

Hi!

Im having 2 components that ineed to see the resulting action when the first
(rotating) component is "hitting" the secanond one., witch is assambled with
2 planar connections. I have seen a demonstratino with 2 spheres colliding
with each other, but i cant figure out how it works.

I have both mechanism dynamics and MBX, any ideas?

 

: Hi!
:
: Im having 2 components that ineed to see the resulting action when the first
: (rotating) component is "hitting" the secanond one., witch is assambled with
: 2 planar connections.

Something doesn't sound right. The first component is rigid, the second assembled
component moves. It is 'connected' to the first component so that one or more
degrees of freedom out of the six available (three planar, three axial) allow it
to move. The connection defintion can include geometric limits of movement,
defined as the distance between two planes or points or other things like
parallelism. Is this how you've set up your connections?

Assuming it is, your next step is to mechanize the moveable assembly by going to
'Applications>Mechanism'. A whole new set of icons should appear on right. The
first one I like to use, to test out my connections, is the the 'hand' icon which
takes you to dynamic drag. Click on the moveable component, move the mouse around
and the component should follow.

Then, set up drivers (motors, either servo or force, attached to connection axes)
to define *how* the part moves. When this is done, create a new analysis, using
the servos you've defined, running for a certain length of time, capturing a
certain number of frames per second. When you run this analysis, pick either
'Quick check' or 'Global interference' to see the results of the interference
study, highlighted in red where the parts interfere.

If this seems complicated, it's not an illusion. PTC has authored a course on it,
one which is available at any school or university with an educational license for
Pro/e. I'm advising you, if you are serious about learning this, to be serious
enough to take the course. Oh, yeah, BTW, this is not some fluff like SolidWorks
"collisions". Mechanisms is actully Mechanica Motion Jr., the setup for doing
stress analysis on moving components.

David Janes

David Janes

 

Last I knew PTC had not developed anything beyond point contact... at
least on the Mechanica side. They did have the ability to allow you to
calculate a "real" amount of bounce based on the hardnesses of the two
materials (which is unique I think) but the guts to what to put in for
values was in some tiny little tech note that later hotline folks would
only say... "That should never have got published" because PTC can't be
responsible for it's use and it goes to far into material properties. Ah
pbbbttt... (The PTC salute!)

I think if you are trying to create planar to planar contact that you
might need to "seed" the area with spheres to get them moved over to
point contacts. Of course, I could be completely wrong, and I completely
agree with David's assessment of complexity. Someday I will dig back
into this... might take years.

-meld

PS: You meant MDX right? Never heard of MBX