大象走路动画（Elephant walk animation）

大象走路动画（Elephant walk animation） 大象走路动画(Elephant walk animation) 2007-09-11 (19:47:57) reprinted with Tags: animation, motion analysis, walking, rhythm, nerves, anatomy, head puppets September 11, 2007 (week 2) at the company and at home ~! Thanks to my brother and my sister for lending me such valuable DVD data, I can thoroughly study the principles of elephant walking by taking advantage of the company project. 1, limbs pace: The 4 limbs of the moving 4 legged animals show us a completely independent body of motion before us, and they can not help but dazzle. Fortunately, only 4, in order to simulate the real, we must sort out the rhythm between the 4 main bodies. First of all, we ignore the hind legs and see how the two forelegs fit together. It is easy to find that, like human walking, it is completely alternating. And when one foot is steady, the other foot lifts, and the feet do not fly at the same time. Completely alternate means, if the complete cycle of a leg stride time as a unit of time (I measure this time for an elephant is about 2 to 3 seconds), then the movement cycle of leg movement relative to the cycle of the contralateral leg just before or after the measures of 0.5 units. This time, in the animation on the slide bar reflects very intuitive. A very simple visual phenomenon, described in words, is very obscure and abstract, but in order to imitate objects realistically, we must substitute logic for the senses and seem to detour around, but there is no shortcut to scholarship. The same conclusion is also suitable for the coordination between the two retreats. Then we'll ignore the side of the leg, just look at the same side of the front and rear legs, so it is not difficult to find, 4 legged animal general rhythm also apply to elephants, namely: foot kicking foot. It means that the same front leg movement cycle is only a little longer than the same hind leg movement cycle. After careful observation and comparison, I found that the length of the measure would never be greater than 0.25 units of time, perhaps 0.2 or 0.15, depending on the circumstances. General is to take the more anxious or closer to the value the greater the running time (running time is just 0.25), when go more slowly or more leisure the smaller values (but not greater than 0. If it's 0, it's inconceivable that the leg and leg should move together. My calculation is: with the eyes on the front left and right foot, right foot lifting time point, in the heart meditation: Da, Da, da...... They raised the order is: the front left and right foot, right foot...... Feel its rhythm. The first "Da" and "Da" between third and 0.5 units of time (the above conclusion has been obtained, the key is to me), of the second "Da" is closer to the first "Da", or closer to the third "Da"? So I found it closer to the third "Da"". So the interval between the second "Da" and the third "Da" is less than 0.25 units of time, and intuitively, the value seems to be between 0.2 and 0.15! So, the problem solved, everything suddenly enlightened. When we make the two, two, and the same side of the front, front and rear, the 3 groups together to make clear, in fact, we have been clear about the 4 independent movement of the overall rhythm between the body. It should be noted that the same side of the forelegs and hind legs at the same time vacated the moment, because the front leg only 0.15 times after the hind leg 0.2 times, before the foot of the ground, the front foot can not wait to lift. I habitually discuss anatomy while analyzing movements. I have observed that the elephant walk because of great weight, in order to save energy and avoid joint sprain, riding down at the foot, important joints (elbow, wrist, knee and ankle) are all straight, rely on the joint ligament effect lock the joints, stiff posture to keep up from before. When the monkeys walk along the ground, the carpal bones and tarsus touch the ground, but the large bones of the carpal bones and tarsus are suspended. It is pointed only with the tips of the fingers and toes. "You must be wondering.", Such a huge weight is how to safely applied in the weak and the phalanx phalanx? In fact, it refers to the 5 and 5 toe pads surrounded by thick, as we hold the principle of human solid ball support to walk, fingertip touchdown, wrist but high, weight is transferred to the ball through the carpal bones, then transfer to the ground by a solid ball. The elephant's hoof and foot structure makes their feet exactly like 4 columns with an enlarged end. Like all 4 erect animals, the elephant's forelimb band is free and the hind limb is fixed. When walking with weight in two alternating between the front legs, left and right scapula (alternate uplift due to ground reaction force of the forelegs, discreet support side of the scapula, long) outline sharp shoulder hump on the back of the lateral contour. Like humans, the elephant's small arm (ulna and radius) attaches to the big arm (humerus) end, the large arm attached to the shoulder blade, the shoulder blade attached to the clavicle, and the clavicle attached to the front of the sternum. The sternum is stationary, and the rotation of the shoulder blades up and down the chest wide surface does not rotate in the coordinated rotation of the acromioclavicular joint and the acromioclavicular joint, making the shoulder movement the most distinctive of all skeletal movements. The height of the shoulder joint (the axis of motion of the large arm) is approximately the middle of the shoulder high line and the high thoracic line. Elbow height (small arm axis) in the chest line, and about the bottom line abdominal flush. The length below the wrist is about 1/2 of the arm length. The height of the hip (the kinematic axis of the thigh) is slightly higher than the shoulder joint. The knee joint (the motor axis of the lower leg) is approximately the same height as the elbow joint. The ankle is approximately the same height as the wrist. Foot forward, elbow forward maximum bending to about 130 degrees, the maximum bending the wrist back to about 90 degrees, the knee back about 115 degrees, the ankle is almost always 180 degrees straight. Since the hind limb is fixed to the spine, the posterior 2/3 segment of the entire hip, hip, and trunk is rotated slightly around the body when the weight is between two and the hind feet. These proportions and movements are only ideal, and the individual differences among elephants are too great. In the Beijing zoo, I have seen the size disparity between thin type and rough dwarf; and long hind forelimb and hindlimb ratio than forelimb length of two types; the spine profile also has at least two types, one is round arc, one is S. Although they all belong to the same species: the Asian elephant. 2, free head ups and downs: Fully coordinated head down the rhythm and pace of the forelegs rhythm, move the head top left foreleg, and then move the head top right front leg, is completely repetitive motion, so the movement cycle length of the head is the forelegs move Britain cycle length (above 1/2 measurement results, one leg walking cycle for 2 to 3 seconds. So Britain head cycle is 1.5 seconds) 1. The whole process of foot lifting before foot is accompanied by the jolt of head jolt. The former foot treads directly cause the head jolt to fall, and the relation of the time point is: the front foot treads the ground, and then drops the head. The downward momentum of the head jolt is relatively urgent, but the motion is relatively slow, but the difference is not as great or even faint as imagined. Such cranial rhythms are apparently caused by two reasons: 1, the forces of inertia. The dynamic static free end is the inertial force against free material base of sudden change of direction, causing the free end towards the force in the opposite direction (such as: the front foot to face a foot to fall, reaction force, the force along the leg until the neck, neck upload, base to the top free head in static inertial interaction force and the gravity of the inevitable drop, drop caused by potential head bumps). 2, dynamic role. If the force used is passive, then the power function is active actuation factor (for example: the whole process of the front side foot caused by riding down in front of the shoulder straps and pulled up the neck of humerus need, the auxiliary force, also rose, causing head bump up potential). It is important to point out that when the head of the free head is up and down, the angle of the head in the sagittal plane has not changed significantly, Therefore, the atlanto occipital joint and all the cervical joints do not rotate at the same angle at the same time, but when the entire neck is viewed on the side, it always stays positive S or anti S. When the skull comes into play, it is accompanied by a weak angle (head down), with the head falling with a weak angle. The principle can be explained by the animation term "follow effect". It is also pointed out that the individual differences in the large image are very large. The neck, neck, or fat individuals are limited in neck motion, and the head motion is weak or flat. In addition, when walking is slower, the conflict between the force and the force is more relaxed, and the driving force is more flexible, so the head jolts are not obvious. When it comes to the role of inertia, I always think of an absurd hypothesis: if the squirrel's soul is transplanted into the elephant's body, what style of movement will the animal have? As smart as a squirrel? Or like an elephant silly blunt? The animal world sport style and has formed rich and varied in different poses and with different expressions, different demeanor and personality of the ocean, these differences are distinguished from each other by dynamic scale between species and different museum specimens, the latter only show the static scale distinguish between species. So we do not expect to retain the extinct species by means of specimens. As far as the animation industry is concerned, what humans have lost is more valuable than what has been left behind. Now, I think I can answer the question: even if the squirrel's soul is transplanted into the elephant's body, the animal still keeps the elephant's movements and character. The reason is that the movement depends on the body rather than the soul, or rarely on the soul. After all, the mechanical factors determine the overall rhythm and style of movement. Although it had a squirrel like mind, it had to spin its head as slowly as an elephant! 3 torso: I took a closer look at the video and didn't seem to see the ups and downs of the forelimb and base of the trunk. But the left and right rotation of the shoulder blades and the rotation of the posterior 2/3 segment are evident. 4, nose, tail, ear: The animation of the nose, tail and ear can be dealt with at last because the movements of the 3 parts are subject to the subject, but can not react to the subject, so it belongs to an isolated unit of motion. Experience tells me never to strain your nose's animation. I'm tired when I do this, but the animation of my nose needs to be focused again. There are two sources of power in the nose: one source is the transmission and attenuation of the force of the head on the nose and the other on the nose, and the other is a voluntary, random swing of the nose. When the elephant walks, the end of its nerve ending nose is restless. The nose animation production process, I think it should be this way: the action from two power sources is broken down into two layers. First, one layer is done independently, and then another layer is done. Here, first of all, to do independent delivery and attenuation animation. The transmission and attenuation of forces are similar to waves, which is the repeated use of the animation term "follow effect". Can I use the old habits, at the same time all rotating joints, and then in the animation on the slide bar from the root to the end in order to detect each one of the key joints backwards the proper distance, so the wave force is formed. The second step, on the basis of the existing animation, add nose independent swing, that is, second independent animation. I find that self swing occurs only in the nose near the end of the 1/3 segment, so the only random swing in 1/3 on it, I try to avoid the key to increase the detection of new habits, in the key investigation on existing overlapping K animation, so you can avoid a lot of trouble. The first layer of animation completely or almost occurred in the sagittal plane (swing), so in the second layer of the best animation occurred in the coronal plane (swing), so in the nose in three-dimensional space with vitality. About the second tier animation, but also to add a little, Even at the end of 1/3 section of the range of motion of animation is not every Beck uniform processing, the range should be from the root tip caused by increasing, the most vivid nose, and always in a certain direction to hook. The nose of the movement is the most spiritual elephant all movement in the flash point, the nose of nerve and muscle complex that silly stupid unbelievable, huge elephant can be used on the nose before and after the two meat disc clip embroidery needle on the ground! The nose is about a little perpendicular to the ground and then grows a little bit. The animation of the tail and ears is much easier. I can finally relax at this stage. If it is not intentional, when the elephant walks, the tail and the ear do not have the independent movement basically, they are only affected by the physical fluctuation of the body. It is a kind of out of order "following effect" of the wave, to tell the truth, then do the analysis at this time is the source of serious superfluous, eyes closed in a good. Interest not, have done talking, pulled two digression! I asked myself, who is the most real animator who walks the elephant? There is no doubt that it is not me, but the elephant, it is itself. But the elephant didn't know all the principles I said! That's really weird! The same is true of us, when we walk, no one ever tells us which muscle to move. Where are the related muscles growing? How to shrink? How to drive bones to do exercise? We know nothing about all of this! But we can coordinate the array of muscle groups, precise completion of walking action, skills are amazing, we marvel at ourselves! Isn't that strange? Experts on the nervous system will say: the brain sends an electrical signal, the signal along a series of neural specific output track on the original transfer to the corresponding muscle fibers, the muscle fiber was stimulated, and the physical and chemical reactions, leading to mechanical contraction...... In this way, an autonomous movement has been completed. But I have to ask, how does the brain select the output track of the electrical signal? You know, the complexity and precision of human motion can not be imagined. If a line track is a puppet of the output signal, then the body of the "puppet line" at least tens of thousands more, and all the "strings" are not separate operation, often to each other are combined into a sophisticated cooperation group, thus, need more control factor can't imagine! Absolutely an astronomical figure! If the brain's information processing center does not have a complete and accurate Atlas of human anatomy, it's hard to imagine how well it can manipulate the situation. But as a matter of fact, we don't have this picture in our brains! Because we can't feel it, we really don't have it in our brains. Logic is so simple! This is really a shocking fact! Shine your eyes, my countrymen! I have another old story, God is always in front of us, but we can not see him because of all kinds of ignorance.