View Full Version : Auto Spider Rig

07 July 2007, 08:29 AM
ate Hi,
a few days ago a friend from work gave me insparation for a new rigging solution,
at least new to me, for dealing with step by step movements like footsteps, or a movement
of a worm for example.
So this weekend I did some testings and developed this rig. (120 MB) (27 Mb) (7MB)
Update - - (15.5 MB)

The basic idea behind it is that the animator animates the progress slider to move a bit
along a path and then stops for a few frames, I set this controller to loop in steps mode so that it would repeat the movement.
then I have a couple of nodes following the first node.
The image below shows how the controller of one of these nodes is built and what the UI looks like.


As you can see it's a path constraint where the percent is controld by a float list.
The first item in that list it an expresion controller that's conected to the progress slider
in the UI. I used an expression to be able to add an ease curve above it.
The ease curve contains a list controller where the first item is the default setting
that makes time move regularly, and the second item is an offset with 1 key and a multiply
curve above it that is controld by the Delay (1 or 2) slider on the UI.
Now we go back to the list controller on the percent, the second item here is called length
and has 1 key with a value and a multiply curve over it connected to the Length or Step
slider on the UI.

To make the spider walk on the surface I used several script controllers with intersectRay functions in them.

I used max 9 with no plugins, though theoreticly this technique could be used on earlier versions of max as well.

I would like to thank Yoni Cohen for the Model and Asaf Amrami for the insperation.

07 July 2007, 08:31 AM
Really nice stuff.
Kudos - this is top league stuff. Especially considering the short amount of time it took you.

Nice model also :)

07 July 2007, 08:47 AM
Great work Matan :)

07 July 2007, 11:22 AM
Wow man, you went far since last thursday...

07 July 2007, 11:36 AM
Nice work. I like the way this has come together.

07 July 2007, 11:51 AM
very cool!
great work, looks so much fun to play with.

keep it up.

07 July 2007, 12:06 PM
:bounce: niiiiice!

07 July 2007, 09:17 PM
Thank you all very much for the replies,
Just wanted to update that I added a link for a compressed version
of the screen capture demonstration on the first post in this thread,
and now it's only 27 MB instead of 120 MB. enjoy..:)

07 July 2007, 06:34 AM
very cool!

i like how you combine the path and normal direction in your control rig, great idea

Rubi Hammer
07 July 2007, 12:09 PM
I posted a comment in the Israeli animation forum but I will post one also here.

I always amazed seeing people completing beautiful rigs in a short time. Seems to me that you can easily develop it into a generic rig for six legs creatures.



07 July 2007, 03:07 PM
a few days ago.. (7MB)

Not Bad, but the walk cycle don't look real to me! :surprised i think you should work on it!


07 July 2007, 04:21 PM
hi guys' thanks for the replies.

Rubi - I gues I could develop an automated walk cycle using this technique.
It will work not only for a hexpedals. Actually in this case it's an octopedal, but for
bipedals, quadropads and even a centipedes. By the way, as I said, I started this from
a solution for a worm walk cycle wich developed into this.

benytone - I guess you'r right, but I never intended to create a good walk cycle,
I didn't have the time to. What you see in the video is actually the result of what
I did in the screen captur video I posted, which took me about 10 minuts.
(it is played in double time so you wont get bored).

and now for the update..
I added a new subRollout in the "Surface Control" rollout.

In this new subRollout (Redefine Path Group) you can see 2 spinners, 2 checkBoxes
and a button. I will describe each one from top to buttom:

Num Ctrls - Defines the number of controllers that curve the upper and lower paths.

Num Steps - Defines the number of in-between controllers on the middle path, to give
extra precision to it.

Show Vector - Hide / Unhide the lookAt vector between the outer paths.

Normalize Path - Tuns on / off constant velocity on the points constraint to the outer
paths and holding the middle one.

Redefine Path - When pressed this executes a script that redefines the 3 paths acording to the parameters 'num Ctrls' and 'num Steps' while preserving as much as possible the shape of the paths.

You can see a demonstration of this new feature on this next link: ( - (15.5 MB)

Thats it for now, if you have any other suggestions I'll be happy to hear them..

07 July 2007, 04:24 PM
Nice - in theory, infact i know it could be done. If you use fourier transforms to proceduralize a hand crafter walk cycle you get the benifit of both world. This would allow for a client/director/animator to have input on the way the spider walks and hand generate it, but also allow for true proceduralism with control of speed, hieght, phase etc - and even effects of the cycle over time.

Rubi Hammer
07 July 2007, 06:25 PM
I also think it is possible.

In a way, the group developing the not yet released "SPORE" computer game provided similar solution.
I do not know how they actually performed this, but the game engine they develop can calculated and provide a solution for rigs created online by the user, automatically adapting nice dynamics and walk cycle (even for tripods).

So here is some inspiration for you:

And sorry for my poor capability of counting :-)

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