Creature Animation 01 – Research

Introduction

This blog mainly records my research on biological animation. I want to make different creature animations, including lions and dragons. So I need to understand the changes in their bones and muscles during exercise. To this end, I have prepared myself plenty of time to explore. I will study in the order of the different bones of different creatures, the walking patterns of quadrupeds, and the flying patterns of birds.

By the way, although I may not be able to complete the animation of different creatures now, it does not mean that I will not do it in the future.

And, this is a blog that has been updated with my practice, because only practice can make me better understand the movement of creatures.

Skeletons of different creatures

Different creatures walk differently. We can divide them into three categories. (Sorry, I don’t know how to translate them)

1. Plantar (human, baboon)

2. Toe walking style (tiger, cat)

3. Hoofing style (sheep, horse)

Through the pictures, we can find that the positions of their thighs, calves and feet are different. This is because carnivores need to hunt, while herbivores need to run fast, and primates (humans) need to have complex movements.

This blog analyses in detail the walking ways of three terrestrial mammals:

http://blog.sina.com.cn/s/blog_17d9a0e8e0102yrog.html

This article explains the advantages and disadvantages of the three types of walking and why they have evolved like this:

https://www.zhihu.com/question/30669356

This article explains the distribution of the leg bones and knees of three terrestrial mammals:

https://www.zhihu.com/question/333980952

The walking pattern of a horse (hoof walking)

We can see that where the front legs are at the highest point, the hind legs are at the lowest point. And the vertical movement rhythm of the head and hind legs is the same. The time interval between the front and rear legs is about 3/4. This is because if the front leg and rear leg pattern of a horse (or other quadruped creature) are the same, a stable triangle cannot be formed between the legs.

This video will explain why the front and rear leg of quadruped creatures use this pattern:

Now we are watching a 2d horse walking animation:

we can find out that:

1. The hips and head of a horse swing up and down together, while the chest (front leg) is just the opposite.

2. In any case, the motion trails of the horse’s head and butt are both 8-figure. In the front view, you can find that they are all moving outwards.

3. The horse’s legs are walking in a straight line, they are very close.

4. Like a human walking animation, the up pose is the highest point, and the down pose is the lowest point.

5. When the hips descend, the belly will move forward, and when the hips rise, the belly will move backward.

Now let’s take a look at the front leg animation of the horse:

we can find out that:

1. The movement of the legs is almost the same as that of a human being.

2. We must pay attention to the changes in the joints. The joints of the legs of horses are not the same as those of humans, and they cannot be bent casually.

3. If the horse’s legs are not straight when touching the ground, the sense of strength cannot be realized.

4. The horse’s joints are like this: when the middle joint moves forward, the bottom joint continues to move backward. Conversely, when the middle joint moves backward, the bottom joint continues to move forward.

This is the walking pattern of the horse in the 2d animation: