Assessment of human operator functional state using a novel differential evolution optimization based adaptive fuzzy model

2012 ◽  
Vol 7 (5) ◽  
pp. 490-498 ◽  
Author(s):  
Raofen Wang ◽  
Jianhua Zhang ◽  
Yu Zhang ◽  
Xingyu Wang
2014 ◽  
Vol 556-562 ◽  
pp. 4065-4068
Author(s):  
Shao Zeng Yang ◽  
Jian Hua Zhang

Operator functional state (OFS) is defined as the time-variable ability that an operator completes his/her assigned tasks. To evaluate the OFS in safety-critical human-machine systems, it is modeled by using the Wang-Mendel-based fuzzy system paradigm in this paper. The fuzzy model is constructed to correlate three EEG features (as model inputs) to the human-machine system performance (as model output). To derive a fuzzy model for real-time OFS assessment, the Gaussian membership function membership crossover point membership gradeδis found to be an essential parameter that controls the robustness of data-driven fuzzy models. The fuzzy models with differentδare applied to the OFS fuzzy modeling. The results have demonstrated that an appropriate value ofδcan be selected to derive robust fuzzy models. Compare with the results obtained by fuzzy models based on symmetric Gaussian membership functions, the new approach based on asymmetric Gaussian membership function leads to considerably improved robustness performance.


2016 ◽  
Vol 10 (5) ◽  
pp. 375-383 ◽  
Author(s):  
Jianhua Zhang ◽  
Zhong Yin ◽  
Shaozeng Yang ◽  
Rubin Wang

Author(s):  
Cao Van Kien ◽  
Ho Pham Huy Anh ◽  
Nguyen Ngoc Son

In this paper, the authors propose a novel adaptive multilayer T-S fuzzy controller (AMTFC) with an optimized soft computing algorithm for a class of robust control uncertain nonlinear SISO systems. First, a new multilayer T-S fuzzy was created by combined multiple simple T-S fuzzy models with a sum function in the output. The multi-layer fuzzy model used in nonlinear identification has many advantages over conventional fuzzy models, but it cannot be created by the writer's experience or the trial and error method. It can only be created using an optimization algorithm. Then the parameters of the multilayer fuzzy model are optimized by the differential evolution DE algorithm is used to offline identify the nonlinear inverse system with uncertain parameters. The trained model was validated by a different dataset from the training dataset to guarantee the convergence of the training algorithm. Second, for robustly and adaptive purposes, the authors have proposed an additional adaptive fuzzy model based on Lyapunov stability theory combined with the optimized multilayer fuzzy. The adaptive fuzzy based on the sliding mode surface is designed to guarantee that the closed-loop system is asymptotically stable has been proved base on a Lyapunov stability theory. Furthermore, simulation tests are performed in the Matlab/Simulink environment that controlling a water level of a coupled tank with uncertain parameters are given to illustrate the effectiveness of the proposed control scheme. The proposed control algorithm is implemented in simulation with many different control parameters, and it is also compared with the conventional adaptive control algorithm and inverse controller. The simulation results also show the superior of the proposed controller than an adaptive fuzzy control or inverse controller when using the least mean square error standard.


2013 ◽  
Author(s):  
James C. Christensen ◽  
Justin R. Estepp ◽  
Glenn F. Wilson ◽  
Christopher A. Russell ◽  
Krystal M. Thomas

2017 ◽  
Vol 86 ◽  
pp. 42-48 ◽  
Author(s):  
Van Cuong Kieu ◽  
Florence Cloppet ◽  
Nicole Vincent

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