Interactive manipulation of rigid body simulations

ABSTRACT

Physical simulation of dynamic objects has become commonplace in computer graphics because it produces highly realistic animations. In this paradigm the animator provides few physical parameters such as the objects' initial positions and velocities, and the simulator automatically generates realistic motions. The resulting motion, however, is difficult to control because even a small adjustment of the input parameters can drastically affect the subsequent motion. Furthermore, the animator often wishes to change the end-result of the motion instead of the initial physical parameters. We describe a novel interactive technique for intuitive manipulation of rigid multi-body simulations. Using our system, the animator can select bodies at any time and simply drag them to desired locations. In response, the system computes the required physical parameters and simulates the resulting motion. Surface characteristics such as normals and elasticity coefficients can also be automatically adjusted to provide a greater range of feasible motions, if the animator so desires. Because the entire simulation editing process runs at interactive speeds, the animator can rapidly design complex physical animations that would be difficult to achieve with existing rigid body simulators.

REFERENCES

• 1: David Baraff, Fast contact force computation for nonpenetrating rigid bodies, Proceedings of the 21st annual conference on Computer graphics and interactive techniques, p.23-34, July 1994 [doi>10.1145/192161.192168]
• 2: David Baraff , Andrew Witkin, Large steps in cloth simulation, Proceedings of the 25th annual conference on Computer graphics and interactive techniques, p.43-54, July 1998 [doi>10.1145/280814.280821]
• 3: Ronen Barzel , Alan H. Barr, A modeling system based on dynamic constraints, Proceedings of the 15th annual conference on Computer graphics and interactive techniques, p.179-188, June 1988
• 4: Ronen Barzel , John F. Hughes , Daniel N. Wood, Plausible motion simulation for computer graphics animation, Proceedings of the Eurographics workshop on Computer animation and simulation '96, p.183-197, December 1996, Poitiers, France
• 5: Dimitri R Bertsekas. Nonlinear Programming. Athena Scientific, Belmont, Massachusetts, 1995.
• 6: Lynne Shapiro Brotman , Arun N. Netravali, Motion interpolation by optimal control, Proceedings of the 15th annual conference on Computer graphics and interactive techniques, p.309-315, June 1988
• 7: Stephen Chenney , D. A. Forsyth, Sampling plausible solutions to multi-body constraint problems, Proceedings of the 27th annual conference on Computer graphics and interactive techniques, p.219-228, July 2000 [doi>10.1145/344779.344882]
• 8: Michael F. Cohen, Interactive spacetime control for animation, Proceedings of the 19th annual conference on Computer graphics and interactive techniques, p.293-302, July 1992
• 9: Bruce Donald , Patrick Xavier , John Canny , John Reif, Kinodynamic motion planning, Journal of the ACM (JACM), v.40 n.5, p.1048-1066, Nov. 1993 [doi>10.1145/174147.174150]
• 10: Nick Foster , Dimitri Metaxas, Realistic animation of liquids, Graphical Models and Image Processing, v.58 n.5, p.471-483, Sept. 1996 [doi>10.1006/gmip.1996.0039]
• 11: Michael Garland , Paul S. Heckbert, Surface simplification using quadric error metrics, Proceedings of the 24th annual conference on Computer graphics and interactive techniques, p.209-216, August 1997 [doi>10.1145/258734.258849]
• 12: Philip E Gill, Walter Murray, and Margaret H. Wright. Practical Optimization. Academic Press, London, 1989.
• 13: Michael Gleicher and Andrew Witkin. Differential Manipulation. In Graphics Interface, pages 61-67, June 1991.
• 14: Michael Gleicher , Andrew Witkin, Through-the-lens camera control, Proceedings of the 19th annual conference on Computer graphics and interactive techniques, p.331-340, July 1992
• 15: F. Sebastin Grassia, Practical parameterization of rotations using the exponential map, Journal of Graphics Tools, v.3 n.3, p.29-48, 1 March 1998
• 16: Radek Grzeszczuk , Demetri Terzopoulos , Geoffrey Hinton, NeuroAnimator: fast neural network emulation and control of physics-based models, Proceedings of the 25th annual conference on Computer graphics and interactive techniques, p.9-20, July 1998 [doi>10.1145/280814.280816]
• 17: Mikako Harada , Andrew Witkin , David Baraff, Interactive physically-based manipulation of discrete/continuous models, Proceedings of the 22nd annual conference on Computer graphics and interactive techniques, p.199-208, September 1995 [doi>10.1145/218380.218443]
• 18: Wilfred Kaplan. Advanced Calculus. Addison-Wesley Publishing Company, Reading, Massachusetts, 1984.
• 19: Zicheng Liu , Steven J. Gortler , Michael F. Cohen, Hierarchical spacetime control, Proceedings of the 21st annual conference on Computer graphics and interactive techniques, p.35-42, July 1994 [doi>10.1145/192161.192169]
• 20: Matthew Moore , Jane Wilhelms, Collision detection and response for computer animationr3, Proceedings of the 15th annual conference on Computer graphics and interactive techniques, p.289-298, June 1988
• 21: J. Thomas Ngo , Joe Marks, Spacetime constraints revisited, Proceedings of the 20th annual conference on Computer graphics and interactive techniques, p.343-350, September 1993 [doi>10.1145/166117.166160]
• 22: James F. O'Brien , Jessica K. Hodgins, Graphical modeling and animation of brittle fracture, Proceedings of the 26th annual conference on Computer graphics and interactive techniques, p.137-146, July 1999 [doi>10.1145/311535.311550]
• 23: Zoran Popović , Andrew Witkin, Physically based motion transformation, Proceedings of the 26th annual conference on Computer graphics and interactive techniques, p.11-20, July 1999 [doi>10.1145/311535.311536]
• 24: Jos Stam, Stable fluids, Proceedings of the 26th annual conference on Computer graphics and interactive techniques, p.121-128, July 1999 [doi>10.1145/311535.311548]
• 25: Robert F. Stengel. Optimal Control and Estimation. Dover Books on Advanced Mathematics, New York, 1994.
• 26: Keith R. Symon. Mechanics, Third Edition. Addison-Wesley Publishing Company, Reading, Massachussetts, 1971.
• 27: Diane Tang, J. Thomas Ngo, and Joe Marks. N-Body Spacetime Constraints. Journal of Visualization and Computer Animation, 6:143-154, 1995.
• 28: Andrew Witkin , Michael Gleicher , William Welch, Interactive dynamics, Proceedings of the 1990 symposium on Interactive 3D graphics, p.11-21, February 1990, Snowbird, Utah, United States
• 29: Andrew Witkin , Michael Kass, Spacetime constraints, Proceedings of the 15th annual conference on Computer graphics and interactive techniques, p.159-168, June 1988

INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
      I.3.6 Methodology and Techniques
          Subjects: Interaction techniques

Additional Classification:
  G. Mathematics of Computing
  G.1 NUMERICAL ANALYSIS
      G.1.7 Ordinary Differential Equations
          Subjects: Boundary value problems

  I. Computing Methodologies
  I.2 ARTIFICIAL INTELLIGENCE
        I.2.10 Vision and Scene Understanding
            Subjects: Modeling and recovery of physical attributes
  I.3 COMPUTER GRAPHICS
      I.3.5 Computational Geometry and Object Modeling
          Subjects: Physically based modeling
      I.3.7 Three-Dimensional Graphics and Realism
          Subjects: Animation

General Terms:
Design, Human Factors, Measurement, Performance, Theory

Keywords:
animation with constraints, physically based animation