Contents
1. Introduction
2. Front Legs - Block Poses
3. Back Legs - Block Poses
4. Timing
5. Body Movement
6. Head and Neck
7. Shoulders and hips
8. More Timing
9. Polish
10. Final Walk Cycle
Hello! In this tutorial, I will be showing you how to animate a quadrupedal walk cycle. This is a character with four legs. It will be a written tutorial, with playblast's of each step so it is easy to follow and so you know if you're are on the right tracks or not. The rig I will be using for this tutorial is creature which has been modeled, rigged, textured and all the rest of it by our group, for our group film for the Post Production unit. As I have been animating with it a lot, I thought it would be a good rig to use. Most good quadruped rigs will have similar controls to our one, so everything I am saying can be applied to free rigs from the internet too.
Before you start animating, it is worth considering some points to help you stay on track and get the most out of the rig you are using.
A) The rig
Before you start any animation, play around with the rig you will be using and get to know every control, what it does, and how it affects other controls (e.g how the feet attributes affect the feet handles when moving them)
B) Personality
Decide how your character will be moving; fast, slow, with lots of energy, really tired, creeping etc. Also, what type of character it is because you don't want to be animating a really heavy character floating around, or vise-versa. Think about its weight and maybe get your rig in some key poses to start bringing its personality out.
C) Style
What style of animation are you going for? Realistic? Exaggerated? etc.
D) Research
Lastly, research. Always get some reference to what you're about to animate. It will help you plan it out and make it clearer in your head of how it is going to move even before you put one key frame down. For this walk cycle I used some books, videos on the internet and other animations I found. Firstly, some good books which I looked at for this are 'Animals in Motion' by Edward Muybridge. This is amazing for photo reference because he shows pretty much each frame of a lions walk cycle in it, so it helps a lot for when you do your first quad cycle. Another is 'Timing for Animation' by Harold Whitaker. This book taught me the basic timing of quad walk cycles, so that's a good one to look at too.
Here is an example of some video references I used too. They are from YouTube:
This is a quick render of the rig I will be using.
Okay so I have decided that I want my creature to be moving quite slowly, as if it is stalking its prey. The front arms are massive, so most of the weight will come from that area, leaving the back legs for the speed. The shoulders would be quite high and head low.
2. FRONT LEGS - BLOCK POSES
First thing about our four legged friends, their front feet and back feet have different timings! As our creature is based on a human, crocodile, gorilla and lion, it is hard to figure out what timing to use, but i want it to move like a lion. Predators of the cat family are very flexible from their spine which gives them a graceful movement and the ability to change direction very fast. They also have more of a radius bone in their front forelegs, more than dogs cows or horses, so they can turn their paws inwards. This is all good stuff to remember when animating.
Animating the front legs is just like a bipedal walk cycle, getting the timing right is important for when we add the back legs to the animation. You can either work in stepped or spline for getting the poses in. I find using spline is easier for walk cycles because they begin with just a simple 'rolling' motion and you can see how its all going to work but its up to you which you use. Also I tend to stay in side view until I have most of the basics down and I move into perspective when I polish off. Here are is the break down, with the key poses (contact points and pass pose's)
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| Frame 3 - Contact |
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| Frame 14 - Pass pose |
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| Frame 23 - Contact |
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| Frame 34 - Pass Pose |
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| Frame 40 - Contact |
This is what it will look like once you have the front legs animated. This timing is only rough at the moment, as we can alter it later when animating the back legs, and then when we come to polishing it off we can adjust them accordingly then too, so don't get stressed over perfect motion just yet.
3. BACK LEGS - BLOCK POSES
Now for the tricky part! This is where timing is all put down in the correct place, well roughly anyway, you can always tweak it slightly later. As for the back legs, they are either 1/2 step ahead of the front legs or 3/4 ahead. This sounds really confusing but I will show you an easy way to make it look right.
Okay, so using the front legs as a guide, think of the back leg as the energy behind the front leg, so it appears as if the back leg is kicking the front leg forward. It's really easy when you scrub through the timeline. (Focus on the green legs below)
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| Frame 6 - Pass Pose |
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| Frame 14 - Contact |
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| Frame 26 - Pass pose |
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| Frame 35 - Contact |
When you have done one side, do the other in the same way, using the front leg as a reference and it should come together and not look totally off balance.
4. TIMING
Once you have all the rough timing in place for the legs, play it over and over on loop. Think about the personality and adjust it accordingly. If it looks of balance, don't worry, we will work on that in the next chapter.
5. BODY
The body is the main area for the primary engergy in this animation. It needs to look balanced as well, so before you animate in anymore detail, set the body accordingly over the legs, making sure it looks balanced for each step it takes. Now we can start moving the rear, and torso.
First, you want to key in the simple up and down motion of the body in time with each step. You will probably move it really high and really low, but if you take a look at your reference materials, you will see the body had a very slight movement up and down.
Once you've done the body as a whole, start to rotate the torso left to right and up and down its self, giving it some over lap to the rear of the body. Again, make sure you time it with each step. You want to angle the shoulders down as the foot makes its contact point until it lifts up again to make a new step. When the foot is at its highest point (pass pose) the shoulder should be at its highest, so rotate the torso the opposite way. It is pretty basic when you can see it in action (below).
6. HEAD AND NECK
Every step the creature takes, his head will overlap slightly and 'bounce' up and down. As the contact is made with the foot, the head will be at its lowest point around 4 - 5 frames after this. This will stagger the motion and give it the feel of the step making his head go up and down, hinting at weight. I have rotated the head down slightly too at its lowest point and as it comes up it straightens out again. This will give you a 'bounce' affect.
Also, you could try rotating the head left to right at each step too, which will break up the rigid feeling of the spine. this will help with the spinal line too, which i have explained later on in this tutorial. Below is what I've just explained in a video.
7. SHOULDERS AND HIPS
I've just been talking about how to add some weight to your animation, but this is where it comes in mostly. The shoulders are going to be the driving force of the walk, and if they don't look right, you're whole animation will start to look wrong and unbelievable. First think you need to understand is as pressure if put on the arm (mid step/pass pose) the shoulder needs to be high. This applies to most walk cycles, but especially for a creep as he will be quite low anyway.
As the foot makes contact, make the shoulders low, and then come up again and to be at the highest point when the foot is at its highest point. Then just before it makes contact again make its low. If you make it low from the highest point faster, it will make the creature seem heavier, as it will look as if its body is dropping down and its arms are taking the weight. Keep the shoulders smooth and play with timing to get it looking how you want it. Below is how I want the shoulders to look like in my creep.
The hips ate also a very important part of the weight, as the do two jobs:
Give weight to the back legs
Add to the spine curves which add to the realistic look
Below are pictures of the contacts for each of the feet. To this point, you wouldn't have touched the hips at all so your animation should look like the pictures on the left. As you can see, indicated by the red lines, the spine curves nicely from the neck to waist, but then it straightens out. You want it to carry on curving like the picture son the right. Use these pictures as a guide to where the hips need to be at each contact point.
In top view, rotate the hips to match the contact points. Use the back legs as a guide to get the spine into a full 'S' shape curve.
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| Back feet: Left foot, left side of hip forwards |
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| Back feet: Right foot, right side of hip forwards |
At this point, stay in top view and rotate the shoulders the same way you have just done the hips. Use the pictures as a guide again.
If all goes to plan, this is what you should have now!
8. MORE TIMING
Now its time to look at it as a whole. You should have something like this:
Now is the time to push and pull key frames about, using either the dope editor or just in the time line. If you want to slow him down, select all the key frames and drag them out, or push them in to speed up your animation. To do this you hold shift and left click on the first frame and drag to the last frame. Then use the arrows on the highlighted time line to stretch and squash it.
As mine is a creep, I want it to be quite slow moving and sneaky so I will slow it down just a tad. When you are happy with what you've got, its time to polish!
9. POLISHING
Polishing is pretty much what it says it is. Polish off all the little areas, and work into them in finer detail to bring out your animation from anyone else's. The small things like the tail, toes, eyes, mouth, elbows and even tweak shoulders and feet arcs. All of these small changes will add to the animation. Use the graph editor to get nice arcs and get it looking nice. You can find a tutorial on how to use the graph editor properly here: Nick Georgeou Graph Editor Tutorial. This is the time to finalise what you have and get it looking exactly how you want it to look.
Things I polished:
Elbow locators
Toe attributes
Neck rotation
Feet arcs
Feet rotation
Knee locators
Tail pivots and movement
Shoulder ease in and out
Torso rotation and translate to add weight
10. FINAL WALK CYCLE
So here we go, the final thing! I rendered it out with all the textures on it. Youtube hasnt done anything for the quality or how long it took me to render this. I used HDR lighting, so that is why his skin looks as if it is sparkling abit, but its about the animation, not the lighting or render! Anyway, here you go and I hope it's been easy enough to follow!
Modeller: Oliver Kane
Rigging artist: Sanjay Sen
Animator: Myself
