Alias

Introduction to Dynamics
Maya 1 Online - Additional Resources Instructor: Adrian Herbez Animation Without Keyframes
Throughout this semester's modules we've been looking at producing animation by directly keyframing attributes on various objects. While using deformers, IK handles, and Set Driven Key can offload the keyframes from one thing to another, they still resolve to setting keyframes byhand. For the most part that's fine, and that's exactly how you'll go about creating the majority of your animations. However, there are situations when manually keyframing everything would be tedious and difficult. While keyframing is how most animation happens, there are at least three alternative approaches that could be taken:
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Expressions/MEL Motion Capture Dynamics

In the case ofexpressions and MEL (Maya's Embedded Language), animation is created via algorithmic, or programming-based means. This is often the easiest way to go about creating simple and/or repetitive animation, but it has a potentially steep learning curve. You'll learn more about expressions and MEL in Maya 2. Motion Capture involves directly recording the motions of an actor of objects in the real worldand applying them to virtual objects and characters. There are a number of different approaches as to how to go about doing that, with the most popular being based on visual tracking of specialized markers. A good example of that kind of approach can be seen in the VICON system . MOCAP systems are generally very expensive. Also, while they do produce incredibly realistic motion, the recordedmotion often requires quite a bit of cleanup. Dynamics is a class of techniques that all share the fact that they produce motion by simulating the physics of the real world. When everything is properly set up, you can get incredibly believable and complex motion with a minimum of effort. Dynamics-based approaches make things that would otherwise be near-impossible relatively straightforward. However,they are quite different from traditional keyframe-based approaches and can take some getting used to.

The Maya Dynamics Family
Just like there's no one application of keyframing in Maya, there isn't a single kind of dynamics. Dynamics is so varied, powerful, and important that it gets it's own tool subset, on par with modeling, animation, and rendering.

Before using dynamics, you'll want toselect it from the drop-down, or hit the F4 key. Dynamics in Maya include:
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Particle Effects Maya: Fluid Effects Maya: Cloth Maya: Hair (new in Maya 6) Soft and Rigid Bodies

Each of the above approaches is good for certain kinds of animation, and they each have their own workflows and idiosyncrasies. They are still more alike than they are different, with each of them involvingthe simulation of real-world forces. In this module, we'll be looking at soft and rigid body dynamics, both because they are in some ways the most flexible of Maya's dynamics systems, and because they serve as a good introduction to dynamics in general.

Rigid and Soft Bodies Defined
Particle systems, fluid effect, cloth, and hair are all great things to work with, and can allow for things thatwould be difficult or impossible otherwise, but they all only apply to one specific kind of thing. Particles only work on particles, cloth only applies to cloth. So what if you have a lovingly crafted model that you want to animate via dynamics? For that, you have to use either soft or rigid body dynamics. Both rigid and soft bodies are ways of getting dynamics to apply to arbitrary pieces ofgeometry in your scene. You can make your models however they need to be and then turn them over to Maya's dynamics system for animation. The difference between soft and rigid bodies is that rigid bodies don't deform, while soft bodies do. Let's start out by looking at an example of when rigid bodies could be really useful and save a great deal of time- animating a bowling ball knocking over pins....