So now we have our main keys, we can actually take a look at breaking this down even further and it's
really easy to get overwhelmed with animation and think, oh, my gosh, I have you know, we only did
four key frames, basically, because, again, that last one is mirrored.
It's the same key frame as the first frame as frame 40 is.
So it really did, you know, four poses here.
And when we look at this animation, we have 40 frames when we think, oh, my gosh, I have to do this
10 times.
What I already did, you know, don't get overwhelmed.
Let's let's break this down.
Let's drag the timeline.
This is what I like to do.
You know what?
Just focus on between two key frames, OK?
Once we have the keys and now we can just take it and piecemeal it down, OK?
We just have this motion to worry about.
Now, don't worry about anything else.
We're going to get this looking right.
OK, so when we look at this, we can think, OK, this is the extreme pose, right?
That's the technical term, the extreme pose.
These are the furthest that these two legs are going to be apart from each other.
Those are the extreme distances.
And we think about extreme distances.
We also have to think, all right, how is this weight being carried?
Is if if it's tripod and the weight is very far out there and there's a lot of weight here in the center
of gravity, it's going to want to fall down.
And while you're walking for these next few frames before this foot picks up the weight, your body
will be going down because basically walking is controlled, falling and you're the foot in front is
basically catching you each time that you fall.
So if that's the case, then we can know that this center of gravity, which actually made a key frame
here, I'm going to delete in my little example there that this qif this center of gravity is not going
to be going up immediately.
Right.
Because this foot hasn't had time to really catch the weight of everything yet.
So what's going to actually happen?
Is this what's going to be going down?
OK, so we can maybe come out here three frames and keep this down on its space bar, have the same
set up I had from the previous lesson.
So I have the graph header down here, another panel.
I'm just I just want to go a little bit past where we started here.
Right.
And the other thing we need to do is get this foot flat because your foot doesn't just hang out on the
heel here.
So when we're going, you know, you're just sliding along the heel, that's not realistic.
We need to get this foot roll down to zero.
So let's get that to zero.
And then you can see that the leg is very straight and that can help us guide us to kind of know biomechanically
how far down with this Kohji need to go to keep that knee from popping and getting too straight, because
if we were up here with this center of gravity then the leg would be far too straight and it would be
a pop right.
When the foot goes flat the knee would be very hyperextended to the point they would pop right here.
So we can use the fact that we know the foot needs to be on the ground to drag them.
Just shift middle mouse, dragging this keyframe down to a point where the knee is no longer, you know,
stretch beyond where it would be hyperextended.
OK, so now when we play this back, the nation pop and it's playing back a little fast, but we can
scrub this.
We can see it's kind of getting hyperextended here and we can fix that by let's go into the center of
gravity.
And instead of this having an auto tangent where it will slowly go down, we probably need to make this
to be straight, go straight down so we can grab these tangents and middle mouse drag them so they're
going straight.
And an easier way to see this would be to go to view infinity.
And now I can see that, you know, this curve is flat lining here.
So we can actually say curves post infinity cycle.
So we can see how these now two key frames relate to each other in a cycle, which is how we'll be using
this.
So it's good to go ahead and see that now so we can see that that kind of tangent continues nicely down
to the bottom here.
So that should help us a little bit to keep the knee from popping.
It looks like it's still popping a little bit and that could maybe be from the foot.
Let's look at the foot and the translate Z.
Now, any time that we are animating and we're moving at a consistent rate with our feet.
Right.
You have to think about this is a special way to animate that.
We're animating on the spot, meaning he's staying on the same he or she is staying in the same spot.
And in reality, they're going to be moving.
Across a distance, and if they are moving across a distance and this foot is going to stay in its place,
then these need to be linear.
They don't need to be, you know, nice, smooth tangents.
So I'm going to go ahead and delete that and I'm going to select all of these and go to a linear motion
here, because as soon as this hits the ground, it should be moving.
And in reality, we might want to move this foot roll zero back a couple frames.
So now it's coming down much sooner and it's working a lot nicer.
So as this vote comes down, we can see now that it's catching the weight of the center of gravity.
And only after that, this is flat and it's catching the weight can the center of gravity go up because
it needs the center of gravity to be pushed up by something.
It just can't float around willy nilly.
We need to understand the motivation and the biomechanics of a walk.
What is actually keeping this center of gravity from falling over?
Well, it's these feet, all right.
And so these keep it upright so we can see that only after that.
This takes the weight of the center gravity can this go back up.
OK, so we wait for that to happen and then this goes back up.
Right.
And that makes sense.
So now we get into this pose cool.
And we can go ahead and make these be linear on trancelike Z on the other foot as well, because we
know that's how we're going to be working.
So let's bring this back up to 40 and just take a look at this one breakdown real quick and see how
much that a little bit of animation added.
We can see the difference between this this foot and this other one.
You can see how this other one kind of floats and the foot roll doesn't cut to the ground.
But the other one, the foot gets to the ground pretty well.
Cool.
So it looks like we could probably, you know, adjust the WI translate now that we have the feet in
linear space.
Remember, when we grab these and now the translate is linear.
Now it's also affecting the distance of the you know, why translate.
So we could even take this.
Let's grab the two top ones and let's experiment a little bit and drag these up.
Looks like it won't be enough.
So maybe we can even bring this up or we can mess with a tangent a little bit.
So.
Let's see if that helps keep this leg straight, because we don't we don't walk bent kneed.
So as you do this, you might find what you have been animating.
Isn't exactly what you need.
Cool, so the other thing to think about is that there's going to be a little motion forward and back
as as you move right, you're going to gain speed and lose speed as you're getting pushed off by your
foot.
So every push off of the foot is going to push your center of gravity forward a little bit so we can
actually push the center of gravity forward and then it can fall backwards as it gets to this in between.
So it's another little thing to think about how this motion actually works.
So let's do that to this one as well, when this hits the ground, we know that the foot roll, you
know, maybe two frames ahead, I believe is what we did on the other one.
That's going to be zero.
This is going to be forward a little bit and we're actually going to do that.
A couple of frames later went take the center of gravity ones and move forward two more frames.
Now, let's play that back.
Might be a little much you can kind of see it kind of bouncing back and forth, so we go to translate
Z and then we can just drag these down.
We can also see where you know this in between we hadn't set for translate Z.
So whereas over here we have this, you know, be at zero.
And that wasn't the case earlier.
So it's going to bounce a little more here.
So let's just drag these values down a little bit.
We don't wanna get too crazy with it.
But just in general, you know, we won't understand the idea of, like, why the center of gravity
is moving the way it is just going to move just very subtly forward.
So the next lesson, let's take a look at these little knee pops and finishing out, you know, these
other passing positions, right.
Right here.
The knee is starting to bend way too soon.
So let's continue to clean this up in the next lesson and then we'll move on to adding the upper body.
Thanks for watching.