PDA

View Full Version : Clone an IK piston duplicating all IK ?


minus
11-28-2003, 11:05 PM
Heyas... I've set up a piston exactly as shown in this tutorial here... (as far as IK goes).. IK_Piston_Tute_for_the_people (http://www.niklasindustries.com/tutorials/tut_hydraulics.htm) .

Now instead of setting up all that IK with all those nulls over again say 3 more times for my object / scene... is there anyway I can just clone the work done?

Also... for anyone who have used pistons in a model... would you say the above IK method would be the preferred approach? -- It's just kinda tedious with all the nulls n' that.

I may have more questions about this later though I'm going to try a few things out first. ;)

SplineGod
11-29-2003, 01:11 AM
You can set up a simpler version using targetting instead of IK.
If you want clones of your IK setup just do a load from scene.

Zeruel the 14th
11-29-2003, 01:14 PM
What a conincidence, just days ago i dug up the same tut out of my tutorial stash and began to mess around. I can't even rig a character properly, so i have very little experience. It took me a while to get my head around it. Afterwhich i wanted to try them on something else. I thought it would be 'easy'. Oh how wrong i was. I'd say getting pistons to move because of something else is some different in itself. I did manage to extend what the original tut did, and get the piston to follow an imaginary wheel. (2 extra nulls, one parented to the other)

I realised i had a SplineGod little piston thingy. Took me a while to pick it apart, being the ignorant person i am (I renamed parts to make it easier for me :blush: ). But i managed to apply that idea to my own experiment.

Yes, i believe the null thing is somewhat tedious, very tedious actually. I've been wracking my brain trying to figure out how i would do something with additional levels of connection involved. Like a 'steel wheel' on a steam train for instance. Piston, sliding thingy, wheel. I think it only gets worse from there...

About this targeting biz...interesting...i must try it. Maybe it won't give me some really cool stuff like the above (:(). But damn it. I'll settle for something that makes simple pistons on things atleast a little easier.

~~~~~~~~~~~~~~~~~~~~
I took the liberty of zipping up my experiment. Seems only right to share. I've included all the 'intermediate' stuff. This will most likely be of no value to anyone who d/l it. It was for my learning benefit more than anything. Perhaps my experiment will help, Minus. I distinctly recall finding a thread on glass and a caustic cube. And that helped me a great deal.

'Piston_Arm_Setup_IK_FINAL.lws' is the only file worth being concerned about. I've made the scene 'me friendly' The schematic is set up. I don't know anyone who uses the schematic...but i do. Its easier for me to visualise. Its just a damn shame its always a mess that needs fixing though. Also, there aren't hardly enough colours to choose from. grrr.

http://home.iprimus.com.au/dman44/IK_Piston_Arm.zip

kretin
11-29-2003, 11:18 PM
I always use targeted bones for pistons. This way you can cheat more, which is always useful :p

Your piston needs 2 weights, one for the base and one for the shaft. Make sure the shaft is a single row of polys, and give the bottom row of points ( the ones embedded in the base) the base weight.

Now put in 2 bones facing each other, parent each bone appropriately, and target each bone to the other bone. Sometimes due to load order, the second bone doesn't target the first properly, so you might need a null parented to the first bone, for the second bone to target.

This way you can contract and stretch the piston far beyond realistic limits, as the shaft is stretching rather than moving within the base, which can be very handy.

Setting this up is real quick and easy, so you can create 3 or 4 setups like this in no time. It also allows you to keep your mesh all in one layer.

CGTalk Moderation
01-16-2006, 07:00 PM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.