Cycle animation is an important and effective process on making an animation, especially for repeat actions like run, walks, etc. Cycles of repeating action are a great help for the animators because reduce the amount of work and this is a great advantage for the entire animation industry.

Cycle animation is used to create a sequence that can be repeated over and over like flags waving, character running, etc. This technique is applicable to computer animation and 2D animation.

 

Image source: http://dominicnobledissertation.blogspot.ro/2014/05/run-cycle-part-1.html

To better understand how a cycle animation works, we will take an example: the walk cycle.  To create a believable walk cycle animation you have to go through the main four poses: contact, recoil, passing and high point.

Image source: http://webneel.com/daily/1-walk-cycle

     1. Contact pose – cycle animation

In walking at least one limb is always in contact with the ground and this represent the first and the most important pose of a walk cycle, the contact. This pose is important because it will determine the walk’s attitude. In this position your character’s leg is at full extension and  foot takes contact with the ground. This pose is at the start and at the end of each step. Also, you should pay attention to the knee, try to keep a slight bend, at foot and arm: when the right foot is forward, the right arm is back and vice versa, shoulders and hip: if one is thrust forward, the other is thrust back.

Image source: http://mgd204.blogspot.ro/2014/06/walk-cycle.html

     2. Recoil pose

Recoil pose is the second main step in the walk cycle animation. It represents the lowest point in the cycle, when the character makes contact with the ground and also the weight goes down on the front leg.

Image source: http://tech-gorilla.com/blog/tuts/animating-a-walk-cycle

     3. Passing pose

Passing pose is the next step. At this pose the character’s legs passes the other to reach the next contact. Be sure that the character’s weight is over the supporting foot, it is at half step and the arms are on the outskirts of the character.

Image source: https://courses.cs.washington.edu/courses/cse464/12wi/assignments/assignment_4/index.html

     4. High-point

The high point is the highest point in the cycle animation. In this position the back foot push on the ground and rise the body to the highest point. After this pose you can repeat the steps for a complete cycle animation.

Image source: http://www.angryanimator.com/word/2010/11/26/tutorial-2-walk-cycle/

If you go through all these stages and pay attention at all parts of the body, you will create a complete and satisfactory cycle animation.

Image source: http://giphy.com/search/walk-cycle-animation-traditional

Bibliography:

Some articles that inspired me and can be helpful for you :

• http://www.fjasmin.net/walk_cycle_tutorial/index.html
• http://blog.digitaltutors.com/12-steps-walk-cycle-animation/
• http://www.cgmeetup.net/home/how-to-create-walk-cycle-animation/