12 Steps to a Great Walk Cycle Animation
Walk cycles are something that every animator needs to know regardless of whether you are a beginner or an experienced animator. Creating believable walk cycles can be the hardest thing to do, but also the most rewarding. They're used in everything from video games, to film, and commercials; so it's of the utmost importance that you can create walk cycles fast while at the same time maintaining high quality.
There are many important steps and animation principles that need to be taken into account. To give you a better understanding, let's take a look at 12 steps to creating a believable walk cycle, and learn how to troubleshoot problems you may run into. By the end of this article you should have the confidence to tackle your own walk cycle.
Step 1 - Find video reference
This step should come as a no-brainer, but it's so important that it is worth mentioning. Video reference is the animator's best tool. Before starting your walk cycle you need to study how the human body moves during a walk.
How do the hips rotate? Where is the weight centered? How many frames does it take for each step? These are the types of questions you should be answering while you study your reference. Even if you find your video reference online, try making your own video reference so you can feel the motions your own body makes as you walk. Remember this is just for your own reference so you don't need an amazing camera for this; any cell phone camera will suffice.
Step 2 - Create the contact position
There are four main positions in a walk that you must block in first. These are the foundation for your animation, as without them, your walk won't feel like a walk. The first of these is the contact pose.
This is the moment when the leg is at full extension and the foot is first contacting the ground. This pose is the start and end of each step and sets the stage for how your walk is going to look. When creating the contact pose don't hyper extend the leg, or have it perfectly straight. Instead keep a slight bend, so as to eliminate some of the popping in the knees that may occur.
Step 3 - Create the down position
When creating a realistic walk cycle, the weight of your character goes down just after the contact. To translate this in your character you will need to create the down position.
This pose shows that the character's full weight has been shifted over to the contacting foot. Since this is the lowest position in the walk, it helps show the weight of the character by how far their hips drop. Make sure not to over do it. To create a more natural walk, make sure your character isn't bobbing up and down.
Step 4 - Create the passing position
The next pose you'll need to create is the pose for when one of your character's legs passes the other. For this, the weight of your character will start to go up for the passing position.
In order to keep that from looking off balance, the weight of your character needs to be over the supporting foot. At this point in the walk the foot is off the ground, your character should be midway through the stride and both arms are at the side of the character. Think of this as the half-way pose.
Step 5 - Create the up position
This is the last of the four main positions in a walk cycle. The character is at the highest point of the walk during the up position and the leg is swinging out at this point as it is preparing to plant on the ground. This position can be thought of as the falling point of the walk.
The character's weight should be leaning forward and at this point the heel of the back foot is the contact position for the foot, so make sure it is rotated up. After your character has the up position blocked in, you should repeat steps two through five to create these four main positions for the opposite leg. Once both steps are blocked in you can simply cycle the animation before starting to refine the animation.
Step 6 - Refine the up and down weight
The weight of your character is something you want to get correct first. To get the proper weight you'll want to adjust the up and down parameter (usually the Translate Y) for the root control.
A good way to get the proper weight is to think of your character's hips as a ball bouncing as it goes up and down. Use this visualization to help you as you adjust the curves to get something similar to a bouncing ball. You may notice this has an affect on the legs, but don't worry about that yet! With most animation you'll want to refine the shot from the root control down. This is simply because any changes you make to the root will affect the legs, so you should make sure everything up the hierarchy looks good before fixing the legs.
Step 7 - Refine the side to side weight
After you've got the up and down movement looking and feeling correct, it's time to go in and refine the side to side movement (usually the Translate X). A good rule of thumb to go by for this is to have the hips directly above the planted foot. Doing this will ensure your character feels balanced when their weight is shifted from side to side.
Make sure the spacing is correct by adjusting the curves in your graph editor. In most cases there is no need to add extra keys at this point as you can most likely get it looking believable by just manipulating the tangent handles.
Step 8 - Refine the chest movement
The upper body of the character can add so much life and appeal to your walk. If your character has big, broad chest rotations it can give the character a bit of an attitude. Depending on what look you're going for you can use this to your advantage or you can try to keep it relatively subtle.
Keep in mind that even if you don't want to add some attitude to your character, you'll still want to incorporate some rotation in the chest to increase its believability. If the arms are moving, so is the chest. No one walks with a chest that is perfectly still.
Step 9 - Add drag and lead and follow to the arms
Once the chest is refined and looking great it's time to go in and adjust the arms. This is the point where you can start adding nice lead and follow, and drag in the arm joints. For example, think of the arms as a chain of movement that mimics the chest. The shoulders move first, followed by the upper arm, the elbow, and finally the wrist.
Have fun with this one and experiment with the amount of overlap and drag that you incorporate into the animation.
Step 10 - Fix any knee popping
After all the work on the upper body is complete, now it's time to focus your attention on fixing any issues with the legs. Usually this means addressing the popping in the knees that will most likely be occurring at this point. This issue is relatively simple to fix. You have a couple options and which one you use will depend on your particular project.
The first technique you can utilize is to take advantage of a leg stretch control that may be available on your rig. If your rig has this, try to shrink or stretch the leg slightly to get rid of the popping. Don't over do it though! This should be used sparingly.
If your rig doesn't have a leg stretch control, an alternative technique you can use is to adjust the hip control to eliminate any popping. The amount of tweaking necessary to eliminate the knee popping should be minimal if you kept a slight bend in the knee when you created the contact position.
Step 11 - Flap the feet
A great way to sell the weight of the character is to have the feet slap firmly on the ground. The feet should go from a raised position to flat within one or two frames. Ease out of the first pose and plant on the next.
By doing this it will give the feet a snappier feel and sell the weight of the character. You can even raise the toe up to add a bit of drag during the ease out pose.
Step 12 - Polish your walk
The final step is to push the walk to the next level. Add the fine details that will enhance the animation. Track all the arcs of the feet and hands. Add some drag in the fingers and head. Refer back to your video reference to find the things that you think will benefit the animation and add in that final 10% of the walk cycle.
Now that you know the 12 important steps for creating a believable walk cycle try it out for yourself! Keep reading more in Creating Walk Cycles with Character and Personality.
Remember that if you ever get stuck along the way you can always refer back to the step-by-step tutorials on Creating Walk Cycles in Maya , Creating Walk Cycles in CINEMA 4D, Creating Walk Cycles in 3ds Max, Creating Walk Cycles in Softimage, Creating Walk Cycles in MotionBuilder to get a more in-depth look at this process.