There are 3 different ways to do inverse kinematics. Everyone needs to read something about each. If you’re interested, you may want to read more. There is a “writing” assignment that goes along with this. This is a little more reading than usual (3 things), but it’s the only reading for the week.
Everyone must (the actual readings are descibed later):
- Read Chapter 5 of Rick Parents book (pdf here). Most of it should be a review of basic graphics and math stuff.
- Read any of the analytic technique papers (I recommend Kovar or Tolani et al).
- Read either of the large database papers (the ones from 2009), and skim the other.
I recommend a little more reading (which is why there is a longer list). My top recommendations
- Maciejewski for understanding the issues.
- Buss for practical stuff on how to implement it
- Rose et. al. since it’s a more practical example-based approach
- Hecker et al. since it’s crazy and cool.
The reading is due for class on Monday, February 18th. Details will be posted on the Moodle page. You will have two answer different questions. One to just indicate which you read, and the other to make you think about it.
The three different categories:
Numerical approaches: the first is a seminal paper is one that really starts to get at core issues with numerical methods. The second is a tutorial of methods applied in practice. The third is an interesting technique with useful features.
- Dealing with the Ill-Conditioned Equations of Motion for Articulated Figures
Anthony Maciejewski in IEEE CG&A, May 1990
Note: this paper is valuable not just because it describes a method for doing IK, but also the geometric and numerical issues involved.
http://dx.doi.org/10.1109/38.55154
(local pdf) - Samuel Buss. Introduction to Inverse Kinematics with Jacobian Transpose, Pseudoinverse and Damped Least Squares methods. http://math.ucsd.edu/~sbuss/ResearchWeb/ikmethods/iksurvey.pdf
- Paolo Baerlocher and Ronan Boulic. An Inverse Kinematic Architecture Enforcing an
Arbitrary Number of Strict Priority Levels. The Visual Computer – VC , vol. 20, no. 6, pp. 402-417, 2004. (pdf) - Chapter 5: Kinematic Linkages in Rick Parent’s Animation Text book (pdf here).
Analytic Approaches:
- Footskate Cleanup for Motion Capture Editing
by Lucas Kovar John Schreiner Michael Gleicher, SCA 2002.
http://www.cs.wisc.edu/graphics/Gallery/kovar.vol/Cleanup
http://www.cs.wisc.edu/graphics/Papers/Gleicher/Mocap/cleanup.pdf - Real-time inverse kinematics techniques for anthropomorphic limbs
by D. Tolani, A. Goswami, and N. Badler, Graphical Models 62 (5), Sept. 2000
(pdf) - Marcelo Kallmann. Analytical inverse kinematics with body posture control. Computer Animation and Virtual Worlds, 19 (2) May 2008. (ACM DL) (found pdf)
Inverse Kinematics by Example: A newer way to solve IK problems is to use a database of examples. This was pioneered by Rose et al, had complicated machine learning math thrown at it, and most recently huge databases.
- Charles F. Rose III, Peter-pike J. Sloan, Michael F. Cohen. Artist-Directed Inverse-Kinematics Using Radial Basis Function Interpolation. Computer Graphics Forum – CGF , vol. 20, no. 3, pp. 239-250, 2001 (pdf)
- Keith Grochow, Steven L. Martin, Aaron Hertzmann, Zoran Popović. Style-based inverse kinematics. ACM Transactions on Graphics – TOG , vol. 23, no. 3, pp. 522-531, 2004. (pdf)
- Wei, X; Chai, J. Intuitive Interactive Human Character Posing with Millions of Example Poses. IEEE CG&A July-August 2011. (ieee)
- Wu, X; Tournier, M; Reveret, L;. Natural Character Posing from a Large Motion Database. IEEE CG&A May-June 2011. (ieee)
Something completely off the wall:
- Chris Hecker. Real-time motion retargeting to highly varied user-created morphologies. SIGGRAPH 2008. (official) (pdf)
How they made SPORE. They had to deal with lots of issues (not just IK). Their IK solution is, non-standard. But nothing about this paper is standard.
