Strength guided motion

ABSTRACT

A methodology and algorithm are presented that generate motions imitating the way humans complete a lifting task under various loading conditions. The path taken depends on "natural" parameters: the figure geometry, the given load, the final destination, and, especially, the strength model of the agent. Additional user controllable parameters of the motion are the comfort of the action and the perceived exertion of the agent. The algorithm uses this information to incrementally compute a motion path of the end-effector moving the load. It is therefore instantaneously adaptable to changing force, loading, and strength conditions. Various strategies are used to model human behavior (such as reducing moment, pull back, add additional joints, and jerk) that compute the driving torques as the situation changes. The strength model dictates acceptable kinematic postures. The resulting algorithm offers torque control without the tedious user expression of driving forces under a dynamics model. The algorithm runs in near-realtime and offers an agent-dependent toolkit for fast path prediction. Examples are presented for various lifting tasks, including one-and two-handed lifts, and raising the body from a seated posture.

REFERENCES

• 1: William W. Armstrong , Mark Green , Robert Lake, Near-real-time control of human figure models, IEEE Computer Graphics and Applications, v.7 n.6, p.52-61, June 1987 [doi>10.1109/MCG.1987.276896]
• 2: E. Asmussen and K. Heeboll-Nielsen. Isometric muscle strength in relation to age in men and women. Ergonomics, 5(1):167-169, 1962.
• 3: M. M. Ayoub, C. F. Gidcumb, M. J. Reeder, M. Y. Beshir, H. A. Hafez, F. Aghazadeh, ~nd N. J. Bethel. Development of an Atlas of Strengths and Establishment of an Appropriate Model Structure. Technical Report, Institute for Ergonomics Research, Texas Tech Univ. (Lubbock, TX), 1981.
• 4: N. I. Badler. Artificial intelligence, natural language, and simulation for human animation. In N. Magnenat- Thalmann and D. Thalmann, editors, State-of-the Art in Computer Animation, pages 19-31, Springer-Verlag (New York), 1989.
• 5: N. i. Badler, P. Lee, C. Phillips, and E. Otani. The Jack interactive human model. In Proceedings o.f the First Annual Symposium on Mechnaical System Design in a Concurrent Engineering Environment, Univ. of iowa, 1989.
• 6: Norman I. Badler , Kamran H. Manoocherhri , Grahm Walters, Articulated figure positioning by multiple constraints, IEEE Computer Graphics and Applications, v.7 n.6, p.28-38, June 1987 [doi>10.1109/MCG.1987.276894]
• 7: D. Baraff, Analytical methods for dynamic simulation of non-penetrating rigid bodies, ACM SIGGRAPH Computer Graphics, v.23 n.3, p.223-232, July 1989
• 8: R. Beckett and K. Chang. An evaluation of the kinematics of gait by minimum energy. Journal of Biomechanics, 1:147-159, 1968.
• 9: J. E. Bobrow. Optimal robot path planning using the minimum-time criteria. IEEE Journal of Robotics and Automation, 4(4):443-450, August 1988.
• 10: D. E Breen. Choreographing goal-oriented motion using cost functions, tn N. Magnenat-Thalmann and D. Thalmann, editors, State-ofithe Art in Computer Animation, pages 141-151, Springer-Verlag (New York), 1989.
• 11: Lynne Shapiro Brotman , Arun N. Netravali, Motion interpolation by optimal control, ACM SIGGRAPH Computer Graphics, v.22 n.4, p.309-315, Aug. 1988
• 12: A. Bruderlin , T. W. Calvert, Goal-directed, dynamic animation of human walking, ACM SIGGRAPH Computer Graphics, v.23 n.3, p.233-242, July 1989
• 13: D. B. Chaflin and G. B. J. Andersson. Occupational Biomechanics. John Wiley & Sons (New York), 1984.
• 14: E. Y. Chao and D. H. Jacobson. Studies of human locomotion via optimal programming. Mathematical Biosciences, 6:239-306, 1971.
• 15: J. Esakov, N. I. Badler, and M. Jung. An investigation of language input and performance timing for task animation. In Graphics Interface "89, pages 86- 93, Morgan-Kanfmann (Palo Alto, CA), Waterloo, Canada, June, 1989.
• 16: Michael Girard, Constrained optimization of articulated animal movement in computer animation, Making them move: mechanics, control, and animation of articulated figures, Morgan Kaufmann Publishers Inc., San Francisco, CA, 1991
• 17: Michael Girard, Interactive design of 3D computer-animated legged animal motion, IEEE Computer Graphics and Applications, v.7 n.6, p.39-51, June 1987 [doi>10.1109/MCG.1987.276895]
• 18: M. Greenisen. NASA Johnson Space Center. personal communication, 1989. Data.
• 19: M. R. Grosso, R. Quach, and N. I. Badler. Anthropometry for computer animated human figures. In N. Magnenat-Thalmann and D. Thalmann, editors, State.of-the Art in Computer Animation, pages 83-96, Springer-Verlag (New York), 1989.
• 20: James K. Hahn, Realistic animation of rigid bodies, ACM SIGGRAPH Computer Graphics, v.22 n.4, p.299-308, Aug. 1988
• 21: V. H. Heyward, S. M. Johannes-Ellis, and J. F. Romer. Gender differences in strength. Research Quarterly .for Exercise and Sport, 57(2):154-159, 1986.
• 22: C. Hoffmann and R. tIopcroft. Simulation of physical systems from geometric models. IEEE Journal ol Robotics and Automation, RA-3(3):194-206, 1987.
• 23: J. M. Hollerbach and K. C. Suh. Redundancy resolution of manipulators through torque optimization. In IEEE Intern. Con}. on Robotic and Auto, pages 1016- 1021, St. Louis, MO, 1985.
• 24: S. N. Imrhan. Modelling lsokinetic Strength o} the Upper Extremity. PhD thesis, Texas Tech Univ., 1983.
• 25: Paul M. Isaacs , Michael F. Cohen, Controlling dynamic simulation with kinematic constraints, ACM SIGGRAPH Computer Graphics, v.21 n.4, p.215-224, July 1987
• 26: M. E. Kahn and B. Roth. The near-minimum time control of open loop articulated kinematic chains. Transactions o} the ASME: Journal of D~tnamic Sitsterns, Measurement, and Control, 93(3):164-172, 1979.
• 27: K. Kazerouni~n and A. Nedungadi. An alternative method for minimization of driving forces in redundant manipulators. In IEEE International Conference on Robotics and Automation, pages 1701-1706, Raleigh, NC, 1987.
• 28: O. Khatib. A unified approach for motion ~nd force control of robot manipulators: the operational space formulation. IEEE Journal of Robotics and Automation, RA-3(1):43-53, 1987.
• 29: L. L. L~ubach. Comparative muscular strength of men and women: ~ review of the literature. Aviation, Space, and Environmental Medicine, 47(5):534- 542, 1976.
• 30: P. Lee. An Archictecture for Modeling Human-like Motion with Constraints. PhD thesis, Dept. of Mechanical Engineering and Applied Mechanics, Univ. of Pennsylvania, Philadelphia, PA, 1990. To appear.
• 31: A. A. Maciejewski and C. A. Klein. Obstacle avoidance for kinematically redundant manipulators in dynamically varying environments. The International Journal of Robotics Research, 4(3):109-117, 1985.
• 32: Gavin S. P. Miller, The motion dynamics of snakes and worms, ACM SIGGRAPH Computer Graphics, v.22 n.4, p.169-173, Aug. 1988
• 33: NASA. The Anthropometry Source Book, Volumes 1 and 11. NASA Reference Publication 1024, Johnson Sp~ce Center, Houston, TX, 1978.
• 34: E. Otani. Software Tools for Dynamic and Kinematic Modeling of Human Motion. Technical Report MS- CIS-89-43, Dept. of Computer and Information Science, Univ. of Pennsylwnia (Philadelphia, PAL), 1989. MSE Thesis, Dept. of Mechanical Engineering and Applied Mechanics, Univ. of Pennsylvania.
• 35: A. Pentland , J. Williams, Good vibrations: model dynamics for graphics and animation, ACM SIGGRAPH Computer Graphics, v.23 n.3, p.207-214, July 1989
• 36: Cary B. Phillips , Jianmin Zhao , Norman I. Badler, Interactive real-time articulated figure manipulation using multiple kinematic constraints, ACM SIGGRAPH Computer Graphics, v.24 n.2, p.245-250, Mar. 1990
• 37: G Sahar , J M Hollerbach, Planning of minimum-time trajectories for robot arms, International Journal of Robotics Research, v.5 n.3, p.90-100, Fall 1986 [doi>10.1177/027836498600500305]
• 38: F. T. Schanne. Three Dimensional Hand Force Capability Model for a Seated Person. PhD thesis, Univ. of Michigan (Ann Arbor, MI), 1972.
• 39: D. Schmitt, A. H. Soni, V. Srinivasan, and G. Naganthan. Optimal motion programming of robot manipulators. Transactions of the ASME: Journal of Mechanisms, Transmissions, and Automation in Design, 107:239-244, 1985.
• 40: S. Singh and M.C. Leu. Optimal trajectory generation for robotic manipulators using dynamic programming. Transactions of the ASME: Journal of Dynamic Systems, Measurement, and Control, 109:88-96, 1987.
• 41: D. Thalmann. Motion control: from keyframe to task level animation. In N. Magnenat-Thalmann and D. Thalmann, editors, State-of the Art in Computer Animation, pages 3-17, Springer-Verl~g(New York), 1989.
• 42: David E. Thompson , William L. Buford, Jr. , Loyd M. Myers , David J. Giurintano , John A. Brewer, III, A hand biomechanics workstation, ACM SIGGRAPH Computer Graphics, v.22 n.4, p.335-343, Aug. 1988
• 43: Jane Wilhelms, Using dynamic analysis for realistic animation of articulated bodies, IEEE Computer Graphics and Applications, v.7 n.6, p.12-27, June 1987 [doi>10.1109/MCG.1987.276893]
• 44: Matthew Moore , Jane Wilhelms, Collision detection and response for computer animationr3, ACM SIGGRAPH Computer Graphics, v.22 n.4, p.289-298, Aug. 1988
• 45: Andrew Witkin , Michael Kass, Spacetime constraints, ACM SIGGRAPH Computer Graphics, v.22 n.4, p.159-168, Aug. 1988
• 46: V. Yen and M. L. N~gurk~. Suboptimal trajectory planning of a five-link human locomotion model. In Biomechanics Proceedings, 1987.
• 47: B.P. Yeo. Investigations concerning the principle of minimal total muscular force. Journal of Biomechan. ics, 9:413-416, 1976.
• 48: D. Zeltzer. Toward an integrated view of 3-d computer animation. The Visual Computer: The International Journal of Computer Graphics, 1(4):249-259, 1985.
• 49: J. Zhao and N.I. Badler. Real Time Inverse Kinematics with Joint Limits and Spatial Constraints. Technical Report MS-CIS-89-09, Dept. of Computer and Information Science, Univ. of Pennsylvania, Philadelphia, PA, 1989.

INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
      I.3.7 Three-Dimensional Graphics and Realism
          Subjects: Animation

Additional Classification:
  H. Information Systems
  H.1 MODELS AND PRINCIPLES

  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
      I.3.5 Computational Geometry and Object Modeling
          Subjects: Geometric algorithms, languages, and systems

General Terms:
Algorithms, Design, Human Factors