QUOTE(brentorama @ 01/27/09, 09:52 PM) [snapback]299741[/snapback]
How to I dynamically constrain one object to another so that they have the characteristics of being welded together (Right now I am using three pin constraints)
Group them and maek the group the rigd body.
QUOTE
Is there a simple way to make a piston-type constraint - that is have an object only movable on the piston axis?
Not really. You cam limit the traslate values in the attribute editor (so it free only to move in one axis), this si enough for pistons but not fr a whole lot of other things.
Mayas not really a simulation software, Also ist a bit pointless to simulate a piston in a rigdbody manner as the real simulation would need to account fr friction, thermodynamics etc etc....* at much higher detail level then mere polygonal surfaces to yeald eny scientific additional data. As a result driving the simulation directly would yeald more accurate simulation. So yes you CAN sue sdks and driven keys with rigdbodies to make any constraint youd ever dream of. So yoru limitation si NOT exatly sane as it says i want to simulate but dont care for theese animation tools, but what if i told you thay are equally simulation tools? Then your thinking is actually disposing of tools you could use anyway.
*note much mre of the behaviour depends on theese things than the actual rigid body simulation. Anyway teh standard way of simulationg collsions dont work too well on tight sliding like this.