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This paper investigates the problem of trajectory tracking control in the presence of bounded model uncertainty and external disturbance. To cope with this problem, we propose a novel intelligent operator-based sliding mode control scheme for stability guarantee and control performance improvement in the closed-loop system. Firstly, robust stabilit...
Contexts in source publication
Context 1
... that compared to the other parameters, the value of integral term δ is comparatively small such that its variation is not easily observable. To make Figure 8 concise, instead of using an amplified curve, the variation of δ is only described and marked by the key points that change in conjunction with other parameters. Also, the variations of fitness value and the linear time-varying inertia weight in Equation (13) are presented in Figure 8. ...
Context 2
... make Figure 8 concise, instead of using an amplified curve, the variation of δ is only described and marked by the key points that change in conjunction with other parameters. Also, the variations of fitness value and the linear time-varying inertia weight in Equation (13) are presented in Figure 8. In Figure 9, the control input, reference tracking, and the derived tracking error are presented. ...
Citations
... For example, research on soft actuators and aluminum plates with Peltier devices have been carried out in [5][6][7], which implied the robustness of RCF systems even with uncertainty. What is more, an intelligent robust operator-based sliding mode control method was proposed in [8], which made RCF theory combine with sliding mode control so as to obtain better tracking performance in nonlinear control system. Therefore, RCF theory is introduced in this paper to achieve robust control combined with the decomposition of hysteresis mentioned above. ...
... Right coprime factorization theory is selected to guarantee the stability of nonlinear control system in this paper. According to the theory [5][6][7][8]14], a given plant operators P : U → V is said to have a right factorization if there exists a linear space W and two stable operator D : W → U and N : W → V such that D is invertible from U to W and P = ND −1 , as shown in Figure 2. Additionally, it is also be proved that the system could be considered as BIBO (Bounded Input Bounded Output) stable if there exists other two stable operators A : V → U and B : U → U, where B is invertible, satisfying the Bezout identity: ...
... To begin with, the scheme of the proposed system without considering external disturbance is shown in Figure 3, while signal r denotes the reference and y denotes the actual output. According to RCF theory, identity operator I is selected as unimodular operator in order to satisfy (8), which suggests that operators A, B, D, and N are expected to satisfy ...
In a nonlinear control system, hysteresis exists usually as common characteristics. In addition, external output disturbances like modelling error, machine friction and so on also occur frequently. Both of them are considered to cause instability and unsatisfactory performance. In this paper, a practical nonlinear control system design is proposed so as to achieve the simultaneous control of input hysteresis and output disturbance. The system is based on RCF (right coprime factorization theory). Additionally, the proposed design has been applied to a soft robotic finger system and the results of simulations and practical experiments are exhibited, which show the effectiveness of the proposed system.
