Optimization of sequential attractor-based movement for compact behaviour generation

In this paper, we propose a novel method to generate optimal robot motion based on a sequence of attractor dynamics in task space. This is motivated by the biological evidence that movements in the motor cortex of animals are encoded in a similar fashion- and by the need for compact movement representations on which efficient optimization can be performed. We represent the motion as a sequence of attractor points acting in the task space of the motion. Based on this compact and robust representation, we present a scheme to generate optimal movements. Unlike traditional optimization techniques, this optimization is performed on the low-dimensional representation of the attractor points and includes the underlying control loop itself as subject to optimization. We incorporate optimality criteria such as e.g. the smoothness of the motion, collision distance measures, or joint limit avoidance. The optimization problem is solved efficiently employing the analytic equations of the overall system. Due to the fast convergence, the method is suited for dynamic environments, including the interaction with humans. We will present the details of the optimization scheme, and give a description of the chosen optimization criteria. Simulation and experimental results on the humanoid robot ASIMO will underline the potential of the proposed approach.

[1]  E. Bizzi,et al.  Linear combinations of primitives in vertebrate motor control. , 1994, Proceedings of the National Academy of Sciences of the United States of America.

[2]  Maja J. Mataric,et al.  Parametric primitives for motor representation and control , 2002, Proceedings 2002 IEEE International Conference on Robotics and Automation (Cat. No.02CH37292).

[3]  Michael Gienger,et al.  Real-Time Self Collision Avoidance for Humanoids by means of Nullspace Criteria and Task Intervals , 2006, 2006 6th IEEE-RAS International Conference on Humanoid Robots.

[4]  Jun Nakanishi,et al.  Control, Planning, Learning, and Imitation with Dynamic Movement Primitives , 2003 .

[5]  Marc Toussaint,et al.  A Primitive Based Generative Model to Infer Timing Information in Unpartitioned Handwriting Data , 2007, IJCAI.

[6]  Maximilian Schlemmer,et al.  Real-Time Collision- Free Trajectory Optimization of Robot Manipulators via Semi-Infinite Parameter Optimization , 1998, Int. J. Robotics Res..

[7]  S. Schaal Movement Planning and Imitation by Shaping Nonlinear Attractors , 2003 .

[8]  Karim Abdel-Malek,et al.  Optimization-based trajectory planning of the human upper body , 2006, Robotica.

[9]  O. von Stryk,et al.  Trajectory optimization of industrial robots with application to computer-aided robotics and robot controllers , 2000 .

[10]  Jun Morimoto,et al.  Learning from demonstration and adaptation of biped locomotion , 2004, Robotics Auton. Syst..

[11]  Christian Igel,et al.  Empirical evaluation of the improved Rprop learning algorithms , 2003, Neurocomputing.

[12]  Yoshihiko Nakamura,et al.  Optimal Redundancy Control of Robot Manipulators , 1987 .

[13]  B. Faverjon,et al.  Probabilistic Roadmaps for Path Planning in High-Dimensional Con(cid:12)guration Spaces , 1996 .

[14]  Jianwei Zhang,et al.  An Enhanced Optimization Approach for Generating Smooth Robot Trajectories in the Presence of Obstacles , 1995 .

[15]  Jun Nakanishi,et al.  Movement imitation with nonlinear dynamical systems in humanoid robots , 2002, Proceedings 2002 IEEE International Conference on Robotics and Automation (Cat. No.02CH37292).

[16]  Steven M. LaValle,et al.  RRT-connect: An efficient approach to single-query path planning , 2000, Proceedings 2000 ICRA. Millennium Conference. IEEE International Conference on Robotics and Automation. Symposia Proceedings (Cat. No.00CH37065).

[17]  Michael Gienger,et al.  Task-oriented whole body motion for humanoid robots , 2005, 5th IEEE-RAS International Conference on Humanoid Robots, 2005..

[18]  Jun Nakanishi,et al.  Learning Attractor Landscapes for Learning Motor Primitives , 2002, NIPS.

[19]  E. Bizzi,et al.  Book Review: Modular Organization of Spinal Motor Systems , 2002, The Neuroscientist : a review journal bringing neurobiology, neurology and psychiatry.