All this talk of walk cycles inspired in me a desire to improve my own.

I kept a true FK construction to my character, but I used JvS's
FindKnee macro to determine the position of the knee, then back
calculated the FK rotational angles to get the points described. This
FK/IK setup will also make it easier to make it do things like walk up
stairs.

Thanks for the advice when I posted actually back in April this same
deal.  I think it's a lot smoother.  Fixing the rotation or bending of
the feet are a whole nuther project for another day.

I still have a love/hate relationship with splines.  Yeah, I could
figure out a way to get it to be very smooth, but then I wouldn't be
able to tweak, retweak, and microtweak if I have 8 extra points to
change every time I make a modification. (2 pts before, 2 pts after x 2
legs= 8 )  >:-P  Note how the "up" ankle travels in a straight triangle.

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Attachments:
Download 'thebodywalker38c.mpg' (289 KB)

"Greg M. Johnson" <"gregj;-)56590\""@aol.c;-)om> wrote in message
news:39d2aac2@news.povray.org...
|
| Thanks for the advice when I posted actually back in April this same
| deal.  I think it's a lot smoother.  Fixing the rotation or bending of
| the feet are a whole nuther project for another day.

The feet tilt upward slightly while midway along the ground, so that needs a
fix.  Also if I remember the physics of biped walking well enough then the
guy needs to lean forward some to fall onto each foot put forward.

|  Note how the "up" ankle travels in a straight triangle.

Are you following any real human walk animations or just going it alone?
The more true to life you try for is going to be more and more a problem I'd
think, never ending.  This character certainly has life-like qualities but
I'm seeing it as a kind of Disney animation right now.  Sorry if that's an
offensive remark, don't mean it to be.
You did those running animations from a year or so ago.  I just looked that
up, done in Animation Master.  Must be a whole other world doing these in
POV-Ray.

Bob

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Bob Hughes wrote:

> The feet tilt upward slightly while midway along the ground, so that needs a
> fix.  Also if I remember the physics of biped walking well enough then the
> guy needs to lean forward some to fall onto each foot put forward.

Good point, and a coding headache for the next iteration.

> Are you following any real human walk animations or just going it alone?

I have Muybridge, and consult it frequently.  The size and shape of the body
were based on a Poser renderings of top, bottom, and side; these were used as a
rotoscope during the construction.

> The more true to life you try for is going to be more and more a problem I'd
> think, never ending.  This character certainly has life-like qualities but
> I'm seeing it as a kind of Disney animation right now.  Sorry if that's an
> offensive remark, don't mean it to be.

That all depends on what you think of Disney.   ;)   The only insulting comment
I've gotten recently was when my work inspired someone to say, "Povray is not a
toy."  Maybe some of the Disneyesquity is from the character of the walk.  But
yes, I wouldn't limit myself only to work that is mistakeable for a photograph:
I'm aiming for the Aardman side of Max Steel in my work.   With its blobbiness
(note kneepit) I could use it as sort of a metal man.  Even if it is "only"
Disney-like, I hope that wouldn't prevent me from making cool T-shirts, a public
service ad or a TV commercial that puts $$ in my pocket, or sell my own
Aardman-like movies. These are the highest callings of raytracing, if I may be
politically incorrect in saying so.

> You did those running animations from a year or so ago.  I just looked that
> done in Animation Master.  Must be a whole other world doing these in POV-Ray.

A:M readily lends itself to boning. In order to get a boned-like system in
povray,  a FK construction with some IK math seemed like the best approach.

Yeah, I need another "bone" in the foot, as in A:M  I had a toe bone.  Right now
the *ankle* moves perfectly, but the foot is just a flat board that does not
move intelligently. My April improvements perfectly fixed the issue of ankle
slippage, now I've got an intelligent knee: next project is the toe.  And with
my new math based on FK +IK, I can truly make it *run,*  i.e.,  have the feet
leave the ground and avoid slipping.

Thanks for the advice.

> Bob

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Bob Hughes wrote:

>   Also if I remember the physics of biped walking well enough then the
> guy needs to lean forward some to fall onto each foot put forward.

Actually, the coding for a leaning-forward upper body wasn't that hard.  New
cycle is at:

 http://members.nbci.com/_XMCM/gregjohn/animation.html#POV16

(Note there is no image to click on for this one animation).

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| Actually, the coding for a leaning-forward upper body wasn't that hard.
New
| cycle is at:
|
|  http://members.nbci.com/_XMCM/gregjohn/animation.html#POV16
|
| (Note there is no image to click on for this one animation).

That looks better alright.  Has a look of momentum in the right direction
this time.  Still looks well suited to stairs.

Bob

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Very robotic! Good work! Or were you trying to go for human...?

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I made further improvements to the cycle and posted it at:

 http://members.nbci.com/_XMCM/gregjohn/animation.html#POV16

(new file in that same old link if you had looked before tonite.)
The foot actually bends like that in a real human.

I was trying for something more or less human-looking......

"Greg M. Johnson" wrote:

> All this talk of walk cycles inspired in me a desire to improve my own.
>
> I kept a true FK construction to my character, but I used JvS's
> FindKnee macro to determine the position of the knee, then back
> calculated the FK rotational angles to get the points described. This
> FK/IK setup will also make it easier to make it do things like walk up
> stairs.
>
> Thanks for the advice when I posted actually back in April this same
> deal.  I think it's a lot smoother.  Fixing the rotation or bending of
> the feet are a whole nuther project for another day.
>
> I still have a love/hate relationship with splines.  Yeah, I could
> figure out a way to get it to be very smooth, but then I wouldn't be
> able to tweak, retweak, and microtweak if I have 8 extra points to
> change every time I make a modification. (2 pts before, 2 pts after x 2
> legs= 8 )  >:-P  Note how the "up" ankle travels in a straight triangle.
>
>   ------------------------------------------------------------------------
>                            Name: thebodywalker38c.mpg
>    thebodywalker38c.mpg    Type: MPEG Video (video/mpeg)
>                        Encoding: base64

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"Greg M. Johnson" <"gregj;-)56590\""@aol.c;-)om> wrote in message
news:39d69c16@news.povray.org...
> I made further improvements to the cycle and posted it at:
>
>  http://members.nbci.com/_XMCM/gregjohn/animation.html#POV16

I hope next year, I will have time for my old plans
for a big video about a future city with solar energy.

What I have all seen in this newsgroups,
trees, walking humans and all the other things,
it was far to complicate at my first trial 1994,
I think this will be a great project.


--

http://www.pege.org clear targets for a confused civilization
http://www.BeingFound.com web design starts at the search engine

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Hi Greg!

The cycle is better now, but still could be improved a lot.

I think the triangle patch of the feet are not so good. Try something
smoother. Same goes for the up-and-down movement of the body. And in reality
I think you don't lift up the feet so much.

I also think it would be a good idea to make the man walk in real-time
instead of slow-motion. That way it is easier to see if the movements look
real.

I don't quite get what the advantage of using the IK/FK technique is. How is
it better than regular IK?

And a suggestion for your animation web page: Having a slow connection I
would prefer that you rearranged the animations so the newest are at the
top. That way I can see the new thumbnails quicker.

I look forward to seeing the further development of your walking technique!

Greetings,

Rune
--
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You raise so many good points I hope I can do justice in replying before the
"slow connection" made worse by using internet radio cuts me off!  At this hour,
my algorithm for walking up stairs has the foot tearing itself from the body and
flinging itself up the stairs! Oh my.

Rune wrote:

> I think the triangle patch of the feet are not so good. Try something
> smoother. Same goes for the up-and-down movement of the body. And in reality
> I think you don't lift up the feet so much.

I need a new technology for smooth motion.  Splines don't cut it. They are fine
for camera paths and lathes.  Yes, once I come up with a perfect, perfect, 97th
revision of exactly what my keyframe positions are to be, I can spend a few
extra hours guessing what points 2 points before and after my active keyframe
positions would work and give a smooth motion: the legacy of cubic splines, and
do this for each of the 5-6 data points for the 10-15 variables getting altered
during the walk.  In a word: bleh.

> I also think it would be a good idea to make the man walk in real-time
> instead of slow-motion. That way it is easier to see if the movements look
> real.
>
> I don't quite get what the advantage of using the IK/FK technique is. How is
> it better than regular IK?

You might be right in that it's not better for everyone starting from scratch,
but at least out of laziness with my current creation, it takes a lot less work,
in that I set up my system as fk.  It is a blob. Everything is based on rotate
translate rotate translate, etc.  I have hundreds of little spheres and
cylinders all over the place, and the construction makes sense to me as FK. The
bicep muscle, for example, is an elongated sphere that sits just a bit forward
in z from the cylinder of the arm bone.  I think you posted a really cool anim
of an alien-like character where the arm & forearm where but a cylinder. I also
think that in a blob, you cannot declare a sub-object and transform and still
have it behave as a blob as everything fits together.

On the other hand,  note the bend in my foot.  The IK is based on the ankle.  Is
there an easy IK-pure solution based on such a complicated foot?

> And a suggestion for your animation web page: Having a slow connection I
> would prefer that you rearranged the animations so the newest are at the
> top. That way I can see the new thumbnails quicker.

Alright will try in the future. Just so you'll know,  XOOM/ nbci's  policy
forbade a direct link, say to members.xoom.com/dude/dudeanim.mpg.

> I look forward to seeing the further development of your walking technique!

Thanks mon.

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