How to : rig rubber hose arms

[Gibble]

Hey Gang!

When I opened up Moho this morning, the demo that launched was a robot that had very interesting rubber hose arms [see below].
You should have it too in your default characters too if you want to analyze the file further.
When you look at the rig though, it uses two bones yet has the rubber hose effect. How was this accomplished??
I love the simplicity of the two-bone solution with the rubber hose resulting from that

upload image

Part 2: could this be set up so the A. shoulder be behind the torso yet the hand/forearm be in front of the torso? If so, how would that be accomplished?? [see below]:

[Ronbo]

Check out Victor's video for the rubber hose arms technique:

https://www.dropbox.com/s/cjdz4zqifhmi3 ... 4?e=2&dl=0

[SimplSam]

There were also recent discussions here about arm techniques: viewtopic.php?t=36899

[Gibble]

Thank you for the recommendations, Ronbo and Simpisam. Those are super helpful!
The Victor Paredes video was the exact information that I was looking for because I wanted to keep using FK for the arms so I can get a nice arc to them when animating.
I didn't think pin bones or a curver would offer the same results an FK rig could offer- or am I wrong?

Victor Paredes Rubber Arm Tutorial

Arm Discussion Thread: these ideas look solid too and I can definitely use them for some other scenarios.

Thanks guys!!

[Víctor Paredes]

Hi, I haven't checked this in a long time, but I think a curver + bones would work better and be more flexible than older setups.

[Gibble]

Thank you for your feedback, Victor. Straight from the original source, you can't beat that!

Does Curvers have FK capabilities? One of the reasons I liked your old solution was because it had forward kinematics and it would animate like a real arm world. Can the Curver method be animated the same way so it will react like a traditional Bone arm would??

Thanks for your input!

[synthsin75]

Yes, you would just bind the curver points to the bones. You just don't need the extra joint bones when using curvers.

[Víctor Paredes]

Exactly,
This tutorial can help you:

[Gibble]

Thanks so much for this video tutorial @Víctor Paredes, that tutorial was exactly what I need to see! You did an excellent job presenting this information, BTW. I love your teaching style. Do you use the ELI5 method (Explain It Like I'm 5 (y.o)? You do a masterful job of taking a complex subject and explaining it in a very easy-to-understand steps. If you didn't do this intentionally, then you are a natural at it It is my favorite way to learn things- and its very effective.
But after watching this brief video, I have a great understanding of the Curver and all of its capabilities! Thanks so much for your great teachings!

And thanks for adding those notes too, @synthsin75. They were so helpful too!

[Gibble]

Follow Up Q:
I am setting up the curver as the tutorial says, but I cannot change the Curver width to match the size of the vector object [see below]
Below you can see the width is 100%:

And here I cranked it up to 355% yet it is the exact same width [see below]

upload pictures online
Is it a View settings issue [see below]? Or is there some other reason the Curver width isn't changing??

(and sorry for being a nuisance)

[Greenlaw]

Just a thought: Could it be a matter of layer scale? Check the size of the Curver layer to see if it's been reduced. When rigging, it's best practice to keep all layers at 100% size on frame zero to prevent situations like that.

[Greenlaw]

Also, if the Curver layer itself is 100%, then it could be the scale of a group layer up the hierarchy affecting it.

[SimplSam]

Your Curver layer appears to be maked in a Group Mask - which is prob why you are not seeing the big green box. Try right clicking the curver layer and setting Masking > Don't mask this layer.

[Gibble]

"Don't Mask this Layer" gets the win!
I didn't know that Curvers were subject to masking too. Thanks for catching and suggesting that SimplSam! Very much appreciated

Could it be a matter of layer scale? Check the size of the Curver layer to see if it's been reduced. When rigging, it's best practice to keep all layers at 100% size on frame zero to prevent situations like that
hmm, good question DR! Everything is default as I just made that layer and didn't change anything. How would I check this scale though as I'd like to be certain (plus it's likely something I'll run into in the future anyway. Here is a snapshot below of a single point says, its at 14%- is this what you mean?? If not, where do I check the scale??

[Greenlaw]

Glad you got that solved, Gibble...and good call, SimplSam!

How would I check this scale though as I'd like to be certain (plus it's likely something I'll run into in the future anyway

To check the current layer's size scale, select the Transform Layer tool. The scale is visible in the tool options bar. If it's 100%, but you still question its scale, check the scale of any parent groups. (If the stroke width or the Curver region is visually smaller or larger than you think it should be, there's probably layer scaling involved.)

BTW, there's nothing technically wrong with scaling layers and groups in frame 0. Scaling layers and groups at frame 0 can be a quick and easy fix in some situations, but you shouldn't do it carelessly, as it can result in scaling conflicts later on.

IMO, it's better to avoid it when rigging. When I'm on frame 0, and I need to scale the vector art, I prefer to transform the points and curves directly.