Assignment 4: Motion Capture
Team assignment
Description
For this assignment, you will use the motion capture lab in GCATT to acquire
motion data, and use that motion data to drive an animated character.
Acquiring MoCap Data
You will use the motion capture setup in the GCATT building (room 130) to
acquire the data. Your contact for doing this is Steve Park (spark@cc.gatech.edu). You should schedule
a time to meet with Steve in the motion capture lab so that someone from your
team can perform some motions. Steve has a list of motions for you to perform.
He will then give you the data files for the motions you performed.
The system you will be using is an optical infrared system. It uses retroreflective
markers, placed on key points on the body, to track motion. When you go to
the mocap lab, you may have the option to use their suit if you wish (check
with Steve). Otherwise, make sure that you wear or bring some clothing that
is not loose-fitting. You want the markers to stay still on your body during
the capture session. Also, don't wear shoes that have highly reflective markings
(such as the retroreflective dots and stripes on some running shoes). These
will interfere with the correspondance algorithm and give you bad data.
Using the MoCap Data
Once you have the mocap data, you will use it to drive the animation of a
human character. There are 2 ways to go about this: (1) programming your
own importer/renderer for the mocap data and model, or (2) using 3D Studio
Max. Note, if you choose the second option (and I suspect most will), youmust
use 3DS Max.
To give you an idea of what each option entails, if you choose the programming
option, you must (1) read in the mocap data, (2) read in the model, (3) figure
out how to map the mocap data to deformations of the model (not trivial).
On the other hand, if you choose to use 3DS Max, you don't have to write
parsers for the data or model, but you have to learn how to use the software.
If you wish to get a good blend between a sequence of motions, the programming
option gives a finer level of control, though.
Regardless of the option you choose, you should create an animation using
a sequence of several of the motions you recorded. For example, you could
tie together walk and turn motions to make a character walking a square path.
Or a run and a running jump to make your character jump from one platform
to another. You should try to blend the animations together so there isn't
a visible "jump" between them, either by using existing modules for 3DS Max,
or by writing your own. A simple linear interpolation of joint rotations using
a slow-in/slow-out function works reasonably well.
Resources for using mocap data in 3DS Max are available here
Some places to get free models: (post more on the swiki if you find any good
ones)
3D Cafe
3D Total
Comments:
See the swiki for
additional help. Please post your questions and experiences there for the
benefit of your classmates.
Every team is expected to do their own work.
You primary contact for gaining access to the motion capture lab is Steve
Park (spark@cc.gatech.edu). Please
choose one member of your team to correspond with Steve, so he isn't overwhelmed
by 40 people sending him emails.
Be sure to schedule a time soon for acquiring your data so you have
plenty of time to work on the animation.
What to Turn In
- A 1+ page write-up descibing how you used the mocap data as well
as describing any problems encountered
- Your original mocap data files (unmodified)
- And other code/tools you created.
- You should submit an animation (AVI, MPEG, or Quicktime), or arrange
to demo your program to the TA if you choose the programming option and cannot
export an animation (I may be able to point you to some C code for writing
an AVI, if you like).
Grading:
Grading for this assignment:
25% Subjective analysis: Quality of animation, blend, etc.
25% Writeup
50% Follows requirements: Did you do what the assignment asked you to
do