Dave -
Below is a snippet of info from the MDX/MDO Central page, on PTC's Knowledge Base.
Here's a link to the top level page:
http://www.ptc.com/cs/cs_25/howto/apm11083/apm11083.html
And the exact TPI number to search for: 114650
<h5>Additional Information</h5>
1. What is Mechanism Dynamics Option?
Mechanism Dynamics Option is an add-on option to Pro/ENGINEER's
Mechanism Design Extension [commonly known as MDX], which allows
designers to simulate real-world dynamic behavior with force motors,
springs, gravity, dampers, impact, and more.
2. Is there any difference between MDX and MDO?
MDX lets designers examine how a mechanism moves [study of kinematics],
whether there is interference and what the space claim envelope looks
like, but it doesn't reveal how fast the mechanism will operate or what
forces are generate. In many situations, desired operations of a
mechanism depend largely on the speed and the forces generated between
its components-designers need MDO to simulate this.
3. Will MDO allow the users to calculate reaction forces and accelerations within the mechanism?
Yes. MDO provides full dynamic simulation including consideration of
gravity, inertia, and applied forces. MDO reports resulting forces
generated by the operation of the mechanism through graphs, tabulated
data, and/or animated vectors.
4. Does MDO have the same functionality as Pro/MECHANICA Motion?
MDO has more functionality than Pro/MECHANICA Motion in some aspects.
MDO will not initially contain all the functionality currently offered
in Pro/MECHANICA Motion [such as "Custom Loads"]. The plan is to
rapidly develop MDO to include all popular Motion functionality.
5. Can the user make use of the licensed MDO module without a license of MDX?
No. MDX license is required in order to make use of MDO functionality.
6. Compared to Pro/MECHANICA Motion, is a compiler [Microsoft Visual
C++] still required to proceed in evaluating the generated equations of
motion?
No. A compiler is no longer required no matter the OS architecture the
product is installed on. The Pro/Engineer engine will carry all the
evaluations.
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.
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The document continues, but the core issue is that the C compiler is no longer needed.
There may be other issues, such as licensing, or application interoperability, that may be preventing you from running the analysis. Part of this is handled during the installation of Pro/E and Mechanica.
-tsl