SYSTEMATIC DESIGN OF A STABLE FUZZY CONTROLLER FOR A ROBOTIC MANIPULATOR USING DESCRIBING FUNCTION TECHNIQUE

This paper designs a kind of adaptive fuzzy controller for robotic manipulator considering external disturbances and modeling errors. First, n-link uncertain robotic manipulator dynamics based on the Lagrange equation is changed into a two-order multiple-input multiple-output (MIMO) system via feedback technique. Then, an adaptive fuzzy logic control scheme is studied by using sliding theory, which adopts the adaptive fuzzy logic systems to estimate the uncertainties and employs a filtered error to make up for the approximation errors, hence enhancing the robust performance of robotic manipulator system uncertainties. It is proved that the tracking errors converge into zero asymptotically by using Lyapunov stability theory. Last, we take a two-link rigid robotic manipulator as an example and give its simulations. Compared with the existing results in the literature, the proposed controller shows higher precision and stronger robustness.

Download Full-text

Nonlinear controller synthesis based on inverse describing function technique in the MATLAB environment

Advances in Engineering Software ◽

10.1016/j.advengsoft.2005.09.009 ◽

2006 ◽

Vol 37 (6) ◽

pp. 370-374 ◽

Cited By ~ 15

Author(s):

Amir Nassirharand ◽

Hassan Karimi

Keyword(s):

Controller Synthesis ◽

Function Technique ◽

Nonlinear Controller ◽

Describing Function

Download Full-text

Vehicle-Follower Longitudinal Control for Automated Transit Vehicles

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.3427114 ◽

1977 ◽

Vol 99 (4) ◽

pp. 241-248 ◽

Cited By ~ 36

Author(s):

R. J. Caudill ◽

W. L. Garrard

Keyword(s):

Steady State ◽

Function Technique ◽

Steady State Response ◽

Describing Function ◽

Transient Responses ◽

Longitudinal Control ◽

Transit Systems ◽

State Response ◽

Acceleration And Deceleration ◽

And Control

This paper examines the effects of spacing policy and control system nonlinearities on the dynamic response of strings of automated transit vehicles operating under automatic velocity and spacing control. Both steady-state and transient responses are studied. Steady-state response is examined by a modification of the describing function technique and transient response is studied by Liapunov procedures. It is shown that a nonlinearity commonly encountered in automated transit vehicles, a limiter on acceleration and deceleration, can result in string instabilities even though a linearized analysis indicates that the string is stable. Although this paper is specifically focused on automated transit systems, some of the results obtained also appear to be applicable to strings of automobiles on freeways.

Download Full-text