SNAKE-ability in Carrara, can anyone figure this out?

protovu

I am not sure if I am stubborn, or just a bonehead, but since RayDream (think late 1980's proto-Carrara) I have been trying to figure out how to snake a cylindrical object along a specific tortuous path. I am not referring to applying a set wave deformer to the object, but rather,
having the the object behave, predictably along a path, just as a snake would.

The closest I have come has been extremely labor intensive use of the bend and twist deformer. But this provides a barely satisfactory use of a single curve at a time. Compound curves are out, as multiple bend and twist deformers, combined with assorted groupings end up distorting the object.

Attached, is a motion path file which shows an example of how I would like the snake object to move.
It contains a sphere which snakes a path between other spheres. With this file, I tried, and had to give up on:
duplicating the motion sphere and staggering the motion of the following spheres by a frame in order to try to have bones (attached to the vertex snake object) track individual spheres as they traveled along the path. .. ridiculous results.

Has anyone else suffered with this? Any ideas? For some reason, I am not being permitted to upload my .car file, nor a .wmv to illustrate.

Thank you,
Protovu

evilproducer

I believe the forum only supports image uploads. Maybe a file sharing site like Drop Box might be the way to go. You could also try an animated gif for the animation.

protovu

http://www.protovu.com/snaketest/

thanks for the reply.
try the link above.

evilproducer

I'll have to try a couple things. I'm rendering in the Batch Queue so I could open the file without effecting my current render, but it's sluggish as all heck.

My first thought is that the snake object should be rigged, and use IK perhaps. Whatever is done, there is going to be some work involved. I'm not sure there is a way to completely automate the process.

Dartanbeck

Have you looked into any of Fenric's Tools for help?
This whole collection adds some fairly essential tools towards animation. I pretty much keyframe everything, myself, so I'm unaware of the proper knowledge to help. But many of the Forum discussions related to the tools in his store, have gone into AMAZING depth on the subjects. Fenric fans and forum responders are really into animation queries.

Edit - Oooops... forgot to hyperlink... here you go!

protovu

Hi evil,
My little file was sluggish?

I did try rigging and using IK. I constrained the vertex object bones with balljoints to eliminate stretching. Could not get the desired snaking.

I also grouped the VO (vertext object ) with a couple of spheres directly above and below. Then I applied a bend and twist, set with limits and a nice tight
curve, to the center of the group. AS I pushed the VO vertically within the group, and it enters the curve area of the deformer, it behaves perfectly..........but that
is for only one curve. Not multiples. Ideally I would like to see the VO snake though 3 curves at once.

Dartanbeck

faba, who is always posting on Fenric threads, has a snaking tutorial for free at shareCG, under the name of fabaone. She uses the ERC plugin to make the thing act however you please - like I said above - Amazing stuff!

protovu

http://www.sharecg.com/v/46194/browse/3/PDF-Tutorial/Carrara-ERC-example-+-description-(path-follow)

I just downloaded, and tried the tutorial above. It is not behaving as the associated image implies. I wonder if it would work on Car7? Actually, it is pretty much
what I was hoping would work. It is basically what I was trying yesterday. Does it work for anyone?

evilproducer

protovu said:

Hi evil,
My little file was sluggish?

I did try rigging and using IK. I constrained the vertex object bones with balljoints to eliminate stretching. Could not get the desired snaking.

I also grouped the VO (vertext object ) with a couple of spheres directly above and below. Then I applied a bend and twist, set with limits and a nice tight
curve, to the center of the group. AS I pushed the VO vertically within the group, and it enters the curve area of the deformer, it behaves perfectly..........but that
is for only one curve. Not multiples. Ideally I would like to see the VO snake though 3 curves at once.

Suggish because I was also rendering and there were particles to calculate at every frame. Your file is fine otherwise. Still trying a couple things before I make any suggestions.

protovu

Ooops.....I seem to need the ERC plugin?? I will try to find, install, and report.

evilproducer

protovu said:

Ooops.....I seem to need the ERC plugin?? I will try to find, install, and report.

Should be available through DAZ. Fenric is the creator, so I assume you could use that to search by as well.

evilproducer

Here's the direct link:
http://www.daz3d.com/shop/carrara-enhanced-remote-control

protovu

will need to pony up $50.
I will get it a little later. Perhaps someone has figured this out within Car. It is not just the money, but I am in the Beta 8.5 now, and I am not sure plugins, or this plugin will work. I would like to revert to 8.1, but for some reason, I cannot remove 8.5, and it is blocking 8.........another story.

evilproducer

8.1 and 8.5 need to be installed in different directories from what I've read. You should be able to have many different versions of Carrara on the same machine.

protovu

yes, I used to have at least 2 versions. Not sure what is going on.

Fenric

I do have to warn that many plug-ins do not work in the current Beta of Carrara 8.5 - so if that is a major concern... well... you're probably right. There are outstanding critical bugs that DAZ has to fix - there is nothing I can do, unfortunately.

I also seem to have been left out of the last couple of sales - my fault, I've been busy with my real job and haven't been able to keep up with the forums here. It would be nice if DAZ could do a little of the work, considering they take half the proceeds, but they don't.

protovu

Hi Fenric,
Thank you for the heads up, and thank you for responding personally.

In the event that I am able to uninstall 8.5, and reinstall 8.1, do you feel that I
would be able to achieve what I am after with ERC tools?

It is important to note that "snaking" is the motion, but not the actual object. Ultimately, I am after
animating a catheter in a tortuous vessel. Distortions in the diameter of the catheter must be miniscule. I was not able to view the worm example in action, but
a worm is a fairly forgiving structure, compared to a catheter.

Fenric

8.1 with ERC can help you do what you want, yes. Setting it up will not be trivial, as you are asking for a significantly non-trivial result. The ultimate problem is that you want a combination of following a path, and a delayed response from each step. ERC provides a delay function, but you will have to set it up for each segment: if you have a hundred segments, then you will have to configure a hundred delays - and you might have to tweak them several times.

I don't want you to spend money (and time) that you don't need to, so I have to ask:

If you have 8.5, have you tried using soft-body physics instead? It might be easier to get your item to react the way you want using that, though you will be at the mercy of the simulation. Keyframe the head of the catheter, and attach the rest of the "tail" to it, then let physics do the work? I don't know exactly how you would set that up, but it might be worth a try.

protovu

I have uploaded my latest attempt to :

http://www.protovu.com/snaketest/

Perhaps someone would like to take a crack at improving it. Seems I have figured out some basics, but I am getting kinking in the vertex model during the travel.

thank you

evilproducer

protovu said:

Hi Fenric,
Thank you for the heads up, and thank you for responding personally.

In the event that I am able to uninstall 8.5, and reinstall 8.1, do you feel that I
would be able to achieve what I am after with ERC tools?

It is important to note that "snaking" is the motion, but not the actual object. Ultimately, I am after
animating a catheter in a tortuous vessel. Distortions in the diameter of the catheter must be miniscule. I was not able to view the worm example in action, but
a worm is a fairly forgiving structure, compared to a catheter.

One is a meat tube and the other a rubberized tube. ;-) Unless it's segmented metal or something. What kind of component shapes are you looking at?

protovu

A rubber tube could work. I am working with a vertex cylinder, basically.

Dartanbeck

See what I mean? Fenric (and those who follow him) is a good breed!

protovu

Fenric said:

8.1 with ERC can help you do what you want, yes. Setting it up will not be trivial, as you are asking for a significantly non-trivial result. The ultimate problem is that you want a combination of following a path, and a delayed response from each step. ERC provides a delay function, but you will have to set it up for each segment: if you have a hundred segments, then you will have to configure a hundred delays - and you might have to tweak them several times.

I don't want you to spend money (and time) that you don't need to, so I have to ask:

If you have 8.5, have you tried using soft-body physics instead? It might be easier to get your item to react the way you want using that, though you will be at the mercy of the simulation. Keyframe the head of the catheter, and attach the rest of the "tail" to it, then let physics do the work? I don't know exactly how you would set that up, but it might be worth a try.

Hi Fenric,
Thank you again for the response. I have not tried soft-body physics. I will look into it.
Thankfully, this question is not tied to any current project.....but it will come up again.

evilproducer

If you decide to go with a rigged object, the more polys the better (within reason). If you use too few, the object won't bend nicely, it'll kink and bulge. The trade off is that if it's too high poly, your machine could get sluggish when manipulating the rigged object. You'll want to experiment a bit to see what works.

There's a couple other things to help keep your model from distorting. Weight painting can help with mesh distortions in your rigged object. You could also limit the movement constraints so that the object can only bend to the point just before it distorts. If you're still getting distortions, maybe you need more bones in the rig.

Roygee

I apologize if I didn't fully understand your question - are you looking for something like this?

http://youtu.be/FoFLuZRbjaA

ckalan1

richard.chaos_91798ec102

If it where me I would use HEXAGON! . there one and use the line tools to make your twisting Spiral PATH the Add a surface function to it. like a circle or whatever. THEN what is cool it that if your are using restricted or full DYNAMICS you can adjust the LINE path..

NOW in Carrara I had to model a bunch of NERVES in a HAND to illustrate a carpal tunnel animation.

I use a very long tapering CONE that had many many segment THEN attached a bones rig. THEN bent it all around the other structures needed.

Then when happy I EXPORTED the NREVE object so it was a FIXED object, import in back in.. What was cool I did in Carrara was then I could use a BONES rig to manipulate the rest of the hand that included the nerves..

HERE is the resuts..

http://www.youtube.com/watch?v=NPPmB_PrmGE

protovu

Roygee said:

I apologize if I didn't fully understand your question - are you looking for something like this?

http://youtu.be/FoFLuZRbjaA

Hi Roygee,
That, I can do.
What I am after is the same idea, but with a nice smooth tube, snaking along a path.

protovu

RichardChaos said:

If it where me I would use HEXAGON! . there one and use the line tools to make your twisting Spiral PATH the Add a surface function to it. like a circle or whatever. THEN what is cool it that if your are using restricted or full DYNAMICS you can adjust the LINE path..

NOW in Carrara I had to model a bunch of NERVES in a HAND to illustrate a carpal tunnel animation.

I use a very long tapering CONE that had many many segment THEN attached a bones rig. THEN bent it all around the other structures needed.

Then when happy I EXPORTED the NREVE object so it was a FIXED object, import in back in.. What was cool I did in Carrara was then I could use a BONES rig to manipulate the rest of the hand that included the nerves..

HERE is the resuts..

http://www.youtube.com/watch?v=NPPmB_PrmGE

Thank you, RichardChaos.
Not sure I understand the relationship to what I am after.