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jeric_synergy
09-19-2015, 11:43 AM
Imagine a stiff spring sticking out of a wall, with a weight on the end. If the wall moves, the spring lags behind slightly, and if something brushes against the weight (perhaps an instanced something) the spring+weight wobbles a bit, then damps down to motionlessness.

How would one rig that? I have not the slightest clue where to start.


Thanks! :thumbsup:

prometheus
09-19-2015, 12:53 PM
some plugins maybe?
https://www.lightwave3d.com/assets/plugins/contains/springy/

or old soft body, maybe new bullet deforming body, and how about the new hinges stuff in 2015?

Just guessing wildly..would have to research those options.

jeric_synergy
09-19-2015, 03:00 PM
I'll give those a look. 2015 Hinges might require TOO many hinges, nicht wahr?

I'd hope to do it with native stuff-- maybe super-stiff SoftFX.

prometheus
09-19-2015, 03:41 PM
I'll give those a look. 2015 Hinges might require TOO many hinges, nicht wahr?

I'd hope to do it with native stuff-- maybe super-stiff SoftFX.
The motor samples with the mars explorer scene seem to look nice with regards to springs..but havenīt looked in to detail on that one.

think bullet deforming body will do fine, might want to check this sample I whipped up now.
spring could have more shape retention or change other values.

Reset the bullet simulation cause I got some weird stuff when loading it directly.

129812

prometheus
09-19-2015, 03:55 PM
Also try activate the shape lock and rotation, lower the shape retention to 20% and check the differences.

jeric_synergy
09-19-2015, 04:13 PM
I haven't checked yet but from the pic: I don't want a vertical spring, which I imagine to be very straightforward, but a horizontal spring-- maybe it's the same, maybe not. Sticking out of a WALL, not a floor.


UNRELATED but: why is the backdrop color contributing to the color of the ground so much?? GI is off. :stumped:

prometheus
09-19-2015, 04:19 PM
I haven't checked yet but from the pic: I don't want a vertical spring, which I imagine to be very straightforward, but a horizontal spring-- maybe it's the same, maybe not. Sticking out of a WALL, not a floor

Well you have to do that for yourself:hammer:

the dynamics principles are pretty much the same and if you understand those, itīs easy for you to create the wall as you want and do a straight spring with divisions, the object need to be set to subdivision last, and it should have itīs beginning inside of the static or rigid bodies

prometheus
09-19-2015, 04:39 PM
for a moving wall, I think I would make the wall a part body, but to move it properly, place a null next to the wall to act a kinematic force, I would suggest, set the scaling of the null to zero, otherwise it will pick up the kinematic radius from the scale of the null.
You would also like to have a track for the wall movement to follow, like in real life.

turn off the dynamics when you move the kinematic null, then turn it on to simulate.

Michael

prometheus
09-19-2015, 05:12 PM
something like this, but of course not upwards like this on the floor..but you get the point or? you have to work on it:D




https://www.youtube.com/watch?v=lCCRYSxyTbE

jeric_synergy
09-19-2015, 05:15 PM
Very nice, that's what I'm going for. I've had some luck w/your scene playing with the Shape Retention (100%), and the stiffness controls. Thanks.

I'm still wondering why the Backdrop Color is contributing so much to the scene illumination when Radiosity is OFF. :stumped:

prometheus
09-19-2015, 05:18 PM
I'm still wondering why the Backdrop Color is contributing so much to the scene illumination when Radiosity is OFF. :stumped:

ah..that is the trick, the backdrop color isnīt contributing at all, there is a fill light (point light) without casting shadows, that is the contributing fill light.
I thought maybe I should set it up with radiosity..but went for the fast way.
the ground is dissolved by distance to blend in with the background.

MonroePoteet
09-19-2015, 05:18 PM
...and, of course, the totally-faked-up approach. The collision is fake, and the spring oscillations are using the Oscillator motion modifier on the SpringWeight object. The IK chain's GoalNull is a child of the SpringWeight.

Fake Fake Fake!! Ah well. BTW, the pellet that's falling to initiate the motion is neutronium. :)

mTp

jeric_synergy
09-19-2015, 05:44 PM
ah..that is the trick, the backdrop color isnīt contributing at all, ..
Try changing the background color.

prometheus
09-19-2015, 06:05 PM
Try changing the background color.

Uhhm..I see what you mean..turning backdrop to black or change color, but as I see it, it only affects one surface..and that is the ground object, the rest is probably just an illusion, though I canīt technicly specify why it looks so different on the ground.

prometheus
09-19-2015, 06:09 PM
I can see the thing causing it, it is because of the ground object is set to dissolve by distance, try turn that off and change backdrop color.

jeric_synergy
09-19-2015, 07:37 PM
I can see the thing causing it, it is because of the ground object is set to dissolve by distance, try turn that off and change backdrop color.
Thanks, I believe you. #aflw --Times like these I REALLY envy C4D users, 'cuz they have a hope in hell of tracking this stuff down: fewer panels that just fragment the attention.

IMO, reverse-engineering a puzzling scene in LW is next to impossible.