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WilliamVaughan
10-09-2008, 05:27 PM
Creating a Piston Rig in 9.5:
Right-Click Here to save (ftp://ftp.newtek.com/multimedia/movies/LW_9/Layout_PistonRig.mov)

Big thanx to Mike and James for their help and support!

shrox
10-09-2008, 05:40 PM
Creating a Piston Rig in 9.5:
Right-Click Here to save (ftp://ftp.newtek.com/multimedia/movies/LW_9/Layout_PistonRig.mov)

Big thanx to Mike and James for their help and support!

I like these tutorials, they are nicely done. Instead of thinking up names for trolls, we should have a name for people that are generous, contributing posters. How about a gifter?

jameswillmott
10-09-2008, 05:55 PM
If you've just watched the video and don't have a piston object lying around, or the time to try out the rig ( but do try it, because it's quick and easy! ) here's the assets Proton used.

The object was supplied by Mike Rizzuto and I've set up the scene the same way Proton did in the video for you to dissect. Enjoy!

WilliamVaughan
10-09-2008, 05:58 PM
Big help James! Much appreciated!

Tobian
10-09-2008, 06:09 PM
Cool, though I still find it confusing :) I guess I will have to experiment with it. Cool stuff! :)

jameswillmott
10-09-2008, 06:15 PM
What do you find confusing? We'll see if we can shed some light on it?

evenflcw
10-11-2008, 08:41 AM
Position by IK... very interesting feature. Thanks to all involved in the making of this video and example scene!

3DGFXStudios
10-13-2008, 02:04 PM
I checked the tutorial out, but now I've a problem. My engine is shaking. (See the attached scene) Somebody know why that is?

WilliamVaughan
10-13-2008, 02:20 PM
You have Position IK on the long neck piece which was not in the video setup and not needed as far as I know.

I'll look for anything else

WilliamVaughan
10-13-2008, 02:22 PM
You have a key frame on frame 10 of your goal


still looking

3DGFXStudios
10-13-2008, 02:25 PM
Oops...that must have slipped in when checking the problem. Without the "oops" it still shakes. mmmm?!?!

hey a cross post.... Cool you're still checking... Thanks!! :)

Maybe it has something to do with the scale of the model. It's huge!!!

WilliamVaughan
10-13-2008, 02:29 PM
holy smokes...20m grid..70meter piston

try it smaller and see what happens

3DGFXStudios
10-13-2008, 02:48 PM
Yup....scaling it down fixed it. Thanks William!!! But it's a little weird that we can't make very bigg pistons....Why is that????

RTSchramm
10-13-2008, 07:19 PM
I have a question, when you confine the piston to the Y axis is this the local Y axis of the piston, or the world axis?

The reason I am asking this is I would like to use this techinque to create a V8 engine.

Rich

Castius
10-13-2008, 08:55 PM
It's the local axis.

WilliamVaughan
10-14-2008, 04:32 AM
Yup....scaling it down fixed it. Thanks William!!! But it's a little weird that we can't make very bigg pistons....Why is that????


Here is the way it was explained to me:

It basically comes down to floating point imprecision. There is a fixed
number of digits available to store a number in a computer. As there are
therefore a finite number of values that can be represented by those
digits, and there are an infinite number of values, logic dictates that
not all values can be exactly represented inside a computer.

In fact, the vast majority of values can only be represented and worked
on approximately, not exactly.

So this leads to something like random noise in the numbers. The noise
is generally very small, but doing lots of maths on those numbers can
amplify the noise.

3DGFXStudios
10-14-2008, 06:09 AM
Ah thnx for explaining. I figured out that if you scale the piston rig in layout there's no problem. I scaled it something like 150000 times and it works fine.

leg63
10-15-2008, 01:09 PM
thank you very much for the tutorial, very clear:)

happens is possible to slide in an object shaped curve?




ps: my english is'nt good..


http://chris.tophevial.free.fr/cinematique1.JPG

RudySchneider
10-15-2008, 10:46 PM
happens is possible to slide in an object shaped curve?

Sure, but you don't need a fancy setup for that. Just set the pivot point for the "handle" to the correct location with respect to its frame:

meshpig
10-16-2008, 02:54 AM
Thanks Proton, neat.


... here's another piston object to play with. It's a twin crank V twin so you just copy the hierarchy over to the second piston so they both rotate on the same crank but at 90 deg.

64685

64683


m

leg63
10-16-2008, 01:24 PM
thank you for your answers :thumbsup:


but i would slide the yellow part with the goal connected to the green part (i use cinematic inverse)

http://chris.tophevial.free.fr/cinematique2.JPG

ghostlight
10-16-2008, 03:22 PM
Thanks for the tutorials on 9.5 rigging! I don't think I'd be able to learn it any other way.

rakker16mm
10-16-2008, 03:46 PM
Thanks Protron,

Great video as always! Please keep them coming because for those of us who are dyslexic it's much preferred to pulling the manual off the shelf :thumbsup:

By the way I just thought I should mention that if you want a smoother running engine you might want to run the counterweight 180 out of phase to the piston and rod to cancel out the vibrations :tsktsk:

It also looks like you might have some issues with uneven cylinder wear and extremely low compression :D

zapper1998
10-16-2008, 04:05 PM
cool.....