Self-Constructing Neural Network Modeling and Control of an AGV

Jafar Keighobadi, Khadijeh Alioghli Fazeli, Mohammad Sadeghi Shahidi

Faculty of Mechanical Engineering, University of Tabriz, Tabriz, Iran.

DOI: 10.4236/pos.2013.42016                

Abstract

Tracking precision of pre-planned trajectories is essential for an auto-guided vehicle (AGV). The purpose of this paper is to design a self-constructing wavelet neural network (SCWNN) method for dynamical modeling and control of a 2-DOF AGV. In control systems of AGVs, kinematical models have been preferred in recent research documents. However, in this paper, to enhance the trajectory tracking performance through including the AGV’s inertial effects in the control system, a learned dynamical model is replaced to the kinematical kind. As the base of a control system, the mathematical models are not preferred due to modeling uncertainties and exogenous inputs. Therefore, adaptive dynamic and control models of AGV are proposed using a four-layer SCWNN system comprising of the input, wavelet, product, and output layers. By use of the SCWNN, a robust controller against uncertainties is developed, which yields the perfect convergence of AGV to reference trajectories. Owing to the adaptive structure, the number of nodes in the layers is adjusted in online and thus the computational burden of the neural network methods is decreased. Using software simulations, the tracking performance of the proposed control system is assessed.

Keywords

Wavelet; Neural Networks; Self-Constructing Dynamical Modeling; Trajectory Tracking

Conflicts of Interest

The authors declare no conflicts of interest.

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