A genetic programming approach based on Levy flight applied to nonlinear identification of a poppet valve

作者：Coelho Leandro dos Santos^*; Bora Teodoro Cardoso; Klein Carlos Eduardo

来源：Applied Mathematical Modelling, 2014, 38(5-6): 1729-1736.

DOI：10.1016/j.apm.2013.09.014

• Nonlinear identification
• Genetic programming
• Levy flight
• Poppet valves
• NARX modeling

Genetic programming (GP) is an evolutionary algorithm-based paradigm inspired by natural evolution to find a generalized hierarchy computer program description. GP adopts a tree-structured code to describe an identification problem. This paper proposed a GP method based on Levy flight to estimate discrete polynomial NARX (Nonlinear Auto-Regressive with exogenous inputs) models. The Levy flight random walks on increments distributed according to a heavy-tailed probability distribution formed by the a-stable distribution family. Besides, Levy flight is a Markov processes. The distance from the origin of the random walk tends to a stable distribution after a large number of steps. These sorts of movements describe not only the fluctuations in share prices, but also natural behaviors as the way in which albatrosses search for food or the flight of many insects. In this paper, the contribution of Levy flight is related to the tune of crossover and mutation probabilities in GP. The proposed GP method based on Levy flight is utilized in an experimental application, a poppet valve. Poppet-type of valve is normally used in combustion engines to open and close intake and exhaust ports in the cylinder head. The very well machined adjust between seat and poppet face gives the sealing feature that is improved every time that the pressure inside the cylinder rises up pushing the valve head against its seat. This type of device is also used in the automotive industry to control the emission levels on combustion engines by recirculating burned gases into the combustion chamber. Results are presented to demonstrate the utility of the proposed GP method based on Levy flight as promising technique in NARX (Nonlinear AutoRegressive with exogenous inputs) model identification of a poppet valve.

• 出版日期2014-3-1