Skip to main content

Spinal Flexibility and its Influence on how Creatures Squash and Stretch.

Animal Movement Breakdowns

Here are a few wonderfully informative extracts from Richard Williams Animator Survival Kit simplifying animating animal locomotion.  If you don't have the book yet go get it, it is a must have for every animator.

        

What the Spine has to Offer?

While touched on a little in the horses gallop I feel Richard Williams doesn't really highlight just how much of an effect the spine has in an animals locomotion.

Unlike people on the move animals spines can undergo some significant compression and stretching, this varies widely depending on the species in question and has real influence in how believable your animation is.

Below are two animals on different ends of the flexible spectrum, despite both having similar timings and footfall patterns (Albeit a longer period of suspension in the lighter hound) the horse and dog have significant differences in the squash and stretch of their bodies from the differing spinal flexibility.


Eadward Muybridges Slides once again to the rescue


For the sake of a bit of fun, here is a rather extreme example of how much influence the spine has on an animals movement can appear:- Quadruped Stiff vs Flexible Spine

Thinking Fictional Spine Time

Bringing the spine into initial planning can be especially important in fantasy creatures where no comparable reference footage can be found. As the most flexible region of the spine is the lumbar its length in relation to the spine as a whole is a great clue as to how much a creatures spine can bend. 





While both the cat and horse have quite close numbers of lumbar vertebrate (7 and 6 respectively) the size of the spines region given is significantly different. When looking at just about the least flexible creature I can think of, the elephant, Its rib cage effectively terminates at the pelvis.

No lumbar =  No Bending.



Example

Here's an example of this theory applied to a fantasy creature that will heavily affect how the animation is handled..

Creature created by Kabiralib

Initially this bulky big cat creature would have an animator perhaps looking to more feline reference footage for inspiration. Although many of its mannerisms may still have roots in a tiger or lion, after investigating its skeletal anatomy I doubt when its on the move it will be anything close to catlike.

From the telling landmarks of where the rib cage ends and the pelvis appears to begin this creature is left with a very limited space for lumbar vertebrate. The result will be a very stiff spine which would leave me now looking into perhaps warthog for my references.
This departure from the obvious inspired by speculative spinal springiness will lead to a much more thought out and interesting creature animation.



I hope this post gives you another element of your creatures to consider and perhaps helps to speed up the animating process.

In another post I will look into another wonderful area of animal study, Types of Predation, as a way to quickly determine how an animal will act when confronted with different external stimulus.



Comments

Popular posts from this blog

Resource - Video Tutorial (Ape like Creature)

Came across this series the other day and thought it was worth sharing here. I find its always quite interesting to see other folks workflows in action. This particular series is fairly old but seems relatively unwatched which I think is unfortunate as it is fairly informative and free which is always a bonus in my book. I would recommend watching the videos at around 1.5x to 2x speed as there is some slow periods, I didn't find I missed anything of what was being said either but each to there own. PART 1 Part 2 Part 3 I also found this very quick video with a tip on using video reference directly in Maya. I will include it too as this wasn't something I had considered in the past however after trying it out Ive found it really can speed up the animating process. 

Truong CG Artist - Great Rig Resource

Creature rigs (for free) can often feel rather scarce, when looking for a job it can be especially necessary to save costs wherever you can. However when the goal is to show your awesome creature animating abilities it  cant hurt to showcase the widest variety possible.  If you havent heard of Truong CG yet then your library of great creature rigs is about to get a lot bigger.  (A few of the rigs on offer from Truongs Gumroad Page) Free Rig Versions Here! Truong offers  an extensive library of rigs they have created themselves amazingly for free. So long as its for non commercial purposes naturally. Whether its dinosaurs, songbirds or demons Truong CG really offers an incredible variety of rigs  that allow animators to just put that wonderful creature knowledge  to use. If you like what Truong is offering and would like to support his efforts you can always add any amount of money to your free rig order. Or if his rigs help your...

Animal Locomotion for Animators - Doctor Stuart S. Sumida

To start things off here is an invaluable resource for any animator looking to get there head round quadruped locomotion. The document linked down below allows an animator just making there first steps into animating four legged creatures to begin to understand the subtleties of four legged movement. The Writer, Dr. Sumida frequently consults with many animation studios from Disney to DreamWorks so his understanding of both animation and the science of animal movement proves invaluable in bridging the gap between the two areas of study. Here are a few excerpts from the pdf, while I strongly suggest you give the whole thing a read these two pages should already offer some insight into the wonderful world of quadruped locomotion. I chose to include a page comparing a trot to a gallop to help illustrate just how varied four legged movement can be. Too often it seems inexperienced animators assume the front and back legs move in a similar fashion to our own. This can result in v...