# CMAC STRUCTURE OPTIMIZATION WITH Q-LEARNING APPROACH AND ITS APPLICATION

### Weiwei Yu, Kurosh Madani, Christophe Sabourin

#### Abstract

Comparing with other neural networks based models, CMAC is successfully applied on many nonlinear control systems because of its computational speed and learning ability. However, for high-dimensional input cases in real application, we often have to make our choice between learning accuracy and memory size. This paper discusses how both the number of layer and step quantization influence the approximation quality of CMAC. By experimental enquiry, it is shown that it is possible to decrease the memory size without losing the approximation quality by selecting the adaptive structural parameters. Based on Q-learning approach, the CMAC structural parameters can be optimized automatically without increasing the complexity of its structure. The choice of this optimized CMAC structure can achieve a tradeoff between the learning accuracy and finite memory size. At last, the application of this Q-learning based CMAC structure optimization approach on the joint angle tracking problem for biped robot is presented.

#### References

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#### Paper Citation

#### in Harvard Style

Yu W., Madani K. and Sabourin C. (2011). **CMAC STRUCTURE OPTIMIZATION WITH Q-LEARNING APPROACH AND ITS APPLICATION** . In *Proceedings of the International Conference on Neural Computation Theory and Applications - Volume 1: NCTA, (IJCCI 2011)* ISBN 978-989-8425-84-3, pages 283-288. DOI: 10.5220/0003694102830288

#### in Bibtex Style

@conference{ncta11,

author={Weiwei Yu and Kurosh Madani and Christophe Sabourin},

title={CMAC STRUCTURE OPTIMIZATION WITH Q-LEARNING APPROACH AND ITS APPLICATION},

booktitle={Proceedings of the International Conference on Neural Computation Theory and Applications - Volume 1: NCTA, (IJCCI 2011)},

year={2011},

pages={283-288},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0003694102830288},

isbn={978-989-8425-84-3},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the International Conference on Neural Computation Theory and Applications - Volume 1: NCTA, (IJCCI 2011)

TI - CMAC STRUCTURE OPTIMIZATION WITH Q-LEARNING APPROACH AND ITS APPLICATION

SN - 978-989-8425-84-3

AU - Yu W.

AU - Madani K.

AU - Sabourin C.

PY - 2011

SP - 283

EP - 288

DO - 10.5220/0003694102830288