DocumentCode :
2097024
Title :
Programmable central pattern generators: an application to biped locomotion control
Author :
Righetti, Ludovic ; Ijspeert, Auke Jan
Author_Institution :
Sch. of Comput. & Commun. Sci., Ecole Polytech. Fed. de Lausanne
fYear :
2006
fDate :
15-19 May 2006
Firstpage :
1585
Lastpage :
1590
Abstract :
We present a system of coupled nonlinear oscillators to be used as programmable central pattern generators, and apply it to control the locomotion of a humanoid robot. Central pattern generators are biological neural networks that can produce coordinated multidimensional rhythmic signals, under the control of simple input signals. They are found both in vertebrate and invertebrate animals for the control of locomotion. In this article, we present a novel system composed of coupled adaptive nonlinear oscillators that can learn arbitrary rhythmic signals in a supervised learning framework. Using adaptive rules implemented as differential equations, parameters such as intrinsic frequencies, amplitudes, and coupling weights are automatically adjusted to replicate a teaching signal. Once the teaching signal is removed, the trajectories remain embedded as the limit cycle of the dynamical system. An interesting aspect of this approach is that the learning is completely embedded into the dynamical system, and does not require external optimization algorithms. We use our system to encapsulate rhythmic trajectories for biped locomotion with a simulated humanoid robot, and demonstrate how it can be used to do online trajectory generation. The system can modulate the speed of locomotion, and even allow the reversal of direction (i.e. walking backwards). The integration of sensory feedback allows the online modulation of trajectories such as to increase the basin of stability of the gaits, and therefore the range of speeds that can be produced
Keywords :
control engineering computing; humanoid robots; legged locomotion; neurocontrollers; position control; stability; biological neural networks; biped locomotion; biped locomotion control; coordinated multidimensional rhythmic signals; coupled adaptive nonlinear oscillators; coupled nonlinear oscillators; coupling weights; differential equations; dynamical system; gaits stability; humanoid robot; intrinsic frequencies; programmable central pattern generators; sensory feedback; Biological neural networks; Centralized control; Control systems; Couplings; Education; Humanoid robots; Legged locomotion; Nonlinear control systems; Oscillators; Signal generators;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Robotics and Automation, 2006. ICRA 2006. Proceedings 2006 IEEE International Conference on
Conference_Location :
Orlando, FL
ISSN :
1050-4729
Print_ISBN :
0-7803-9505-0
Type :
conf
DOI :
10.1109/ROBOT.2006.1641933
Filename :
1641933
Link To Document :
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