Lipschitz continuous sliding-mode controllers (LCSMC) are developed as the integral of discontinuous SMC, producing control signals of finite slope. Nevertheless, LCSMC still generate chattering in the presence of fast parasitic dynamics. In this paper, an analysis of chattering in systems driven by LCSMC is performed using the Harmonic Balance (HB) approach. Two kinds of LCSMC are considered: the first one is based on a linear sliding variable (LSV) and the second one on a terminal switching variable (TSV). Predictions of the amplitude and frequency of self-excited oscillations allowed to compute the average power consumed by the controller, in order to maintain the trajectories into the real sliding mode. A comparison of LCSMC with the Super-Twisting controller (STC), which produce a continuous control signal with infinite slope, is performed. Theoretical predictions and simulation results confirm that LCSMC may induce fast-oscillations (chattering) of smaller amplitude and average power than those ones caused by the STC. But, surprisingly, the chattering generated by LSV-LCSMC could be smaller than that one caused by TSV-LCSMC, when the actuators are fast enough. On the other hand, it tuns that if the sliding dynamics of the LSV-LCSMC closed-loop is of similar speed as the actuators dynamics, the system can loose even practical stability.
In this work, a new SMS is proposed to achieve high tracking and suitable robustness. However, the chattering phenomenon should be regarded as the main drawback of the SMC. Therefore, a new compound control algorithm is used for reducing the chattering phenomenon. The applied compound control law constantly evaluates the error and send the correct value to the system. This significantly will reduce the chattering phenomenon. The performance of the control methods validated by applying on a robot arm experimentally.
The problem we focus on in this paper is to find a nearly optimal sliding mode controller of continuous-time nonlinear multiple-input multiple-output (MIMO) systems that can both reduce chattering and minimize the cost function, which is a measure of the performance index of dynamics systems. First, the deficiency of chattering in traditional SMC and the quasi-SMC method are analyzed in this paper. In quasi-SMC, the signum function of the traditional SMC is replaced with a continuous saturation function. Then, a chattering reduction algorithm based on integral reinforcement learning (IRL) is p…
In this research we propose a new compound Fractional Order Sliding Mode Controller (FOSMC) and SuperTwisting Controller (FOSMC+STC) to control of a MEMS gyroscope. A new sliding mode surface has been defined to design the proposed new sliding mode controller. The main advantages of a FOSMC is its high tracking performance and robustness against external perturbation, but it is susceptible to chattering. By augmenting a STC with a FOSMC, the chattering phenomenon is eliminated, singularity problem is solved and systems robustness has significatnetly improved. Simulation results validate the ef…
In this article, I introduce the notion of Fuzzy-based Higher adaptive order sliding mode observers through the example of the super-twisting adaptive order sliding mode observer. I begin by presenting the super-twisting second order sliding mode observer for systems in triangular form. Then I replace the sign functions with fuzzy inference systems in order to eliminate the chattering effect. I then show that this variant of the super-twisting second order sliding mode observer may not converge depending on the input, so I replace the square root with an adaptive power $γ$. The efficiency of t…
To reduce the chattering and overestimation phenomena existing in classical adaptive sliding mode control, this paper presents a new class K_infinity function-based adaptive sliding mode control scheme. Two controllers are proposed in terms of concave and convex barrier functions to implement this kind of control methodology. To avoid large initial control magnitudes, two modified control schemes are provided, which extend the proposed methodology to different scenarios. It is proven that the proposed controllers yield finite-time convergence to a real sliding mode. Finally, simulations and di…
Dynamic Sliding Mode Control based on Fractional calculus subject to uncertain delay based chaotic pneumatic robot
Farabina Noshirvani’s smart Co.（法拉比亚·诺希拉维智能公司）；Robotic Research Lab.（机器人研究实验室）；Faculty of Electrical and Robotic Engineering, Shahrood University of Technology（沙霍尔德大学电气与机器人工程学院）
In this work, we propose a new passivity-based sliding mode control method for mechanical port-Hamiltonian systems. Passivity-based sliding mode control (PBSMC) is unification of sliding mode control and passivity-based control. It achieves sliding mode control and Lyapunov stability simultaneously by employing an energy based Lyapunov function. The proposed method gives a family of stabilizing controllers which smoothly interpolates passivity-based control and sliding mode control with free parameters. The freedom is useful to adjust the trade-off between robustness against external disturban…
First and High Order Sliding Mode-Multimodel Stabilizing Control Synthesis using Single and Several Sliding Surfaces for Nonlinear Systems: Simulation on an Autonomous Underwater Vehicles (AUV)
Ecole Polytechnique de Tunisie（突尼斯高等理工学院）；L.S.A Laboratoire des Systèmes Avancés（先进系统实验室）
The current paper presents a Sliding Mode Controller (SMC) for indirect field-oriented Cascaded Doubly Fed Induction Generator (CDFIG) powered through a Matrix Converter (MC). The proposed SMC employs a continuous control strategy to accomplish free chattering fractional-order sliding-mode control and to ensure that the control of the first DFIG stator's reactive and active power is separated. An MC is used to control the current provided to the second stator of the CDFIG as an alternative to standard voltage source inverters. The two MCs are controlled via Space-Vector Pulse-Width Modulation …
This paper presents a novel adaptive fast smooth second-order sliding mode control for the attitude tracking of the three degree-of-freedom (3-DOF) helicopter system with lumped disturbances. Combining with a non-singular integral sliding mode surface, we propose a novel adaptive fast smooth second-order sliding mode control method to enable elevation and pitch angles to track given desired trajectories respectively with the features of non-singularity, adaptation to disturbances, chattering suppression and fast finite-time convergence. In addition, a novel adaptive-gain smooth second-order sl…
This paper presents three types of sliding mode controllers for a magnetic levitation system. First, a proportional-integral sliding mode controller (PI-SMC) is designed using a new switching surface and a proportional plus power rate reaching law. The PI-SMC is more robust than a feedback linearization controller in the presence of mismatched uncertainties and outperforms the SMC schemes reported recently in the literature in terms of the convergence rate and settling time. Next, to reduce the chattering phenomenon in the PI-SMC, a state feedback-based discrete-time SMC algorithm is developed…
Adaptive type-2 fuzzy second order sliding mode control for nonlinear uncertain chaotic system
QUERE Laboratory, Engineering Faculty, University of Setif 1（塞提夫第一大学工程学院QUERE实验室）；CReSTIC of Reims Champagne-Ardenne University,IUT de Troyes（兰斯香槟-阿登大学CReSTIC中心特鲁瓦高等师范学院）
In this thesis, advanced design technique in sliding mode control (SMC) is presented with focus on PID (Proportional-Integral-Derivative) type Sliding surfaces based Sliding mode control with improved power rate exponential reaching law for Non-linear systems using Modified Particle Swarm Optimization (MPSO). To handle large non-linearities directly, sliding mode controller based on PID-type sliding surface has been designed in this work, where Integral term ensures fast finite convergence time. The controller parameter for various modified structures can be estimated using Modified PSO, which…
Consensus formation tracking of multiple autonomous underwater vehicles (AUVs) subject to nonlinear and uncertain dynamics is a challenging problem in robotics. To tackle this challenge, a distributed bioinspired sliding mode controller is proposed in this paper. First, the conventional sliding mode controller (SMC) is presented, and the consensus problem is addressed on the basis of graph theory. Next, to tackle the high frequency chattering issue in SMC scheme and meanwhile improve the robustness to the noises, a bioinspired approach is introduced, in which a neural dynamic model is employed…
Ultrasonic motors (USMs) are commonly used in aerospace, robotics, and medical devices, where fast and precise motion is needed. Remarkably, sliding mode controller (SMC) is an effective controller to achieve precision motion control of the USMs. To improve the tracking accuracy and lower the chattering in the SMC, the fractional-order calculus is introduced in the design of an adaptive SMC in this paper, namely, adaptive fractional-order SMC (AFOSMC), in which the bound of the uncertainty existing in the USMs is estimated by a designed adaptive law. Additionally, a short memory principle is e…
Adaptive Gains to Super-Twisting Technique for Sliding Mode Design
Harbin Institute of Technology, Shenzhen（哈尔滨工业大学（深圳））；Shenzhen Key Lab of Mechanisms and Control in Aerospace（深圳市航天机构与控制重点实验室）；Indian Institute of Technology (BHU), Varanasi（印度理工大学（贝拿勒斯））；Yanbian University（延边大学）
This paper presents a novel Sliding Mode Control (SMC) algorithm to handle mismatched uncertainties in systems via a novel Self-Learning Disturbance Observer (SLDO). A computationally efficient SLDO is developed within a framework of feedback-error learning scheme in which a conventional estimation law and a Neuro-Fuzzy Structure (NFS) work in parallel. In this framework, the NFS estimates the mismatched disturbances and becomes the leading disturbance estimator while the former feeds the learning error to the NFS to learn system behavior. The simulation results demonstrate that the proposed S…
This paper deals with the design of robust tracking and model following (RTMF) controller for linear time-invariant (LTI) systems with uncertainties. The controller is based on the second order sliding mode (SOSM) algorithm (super twisting) which is the most effective and popular in the family of higher order sliding modes (HOSM). The use of super twisting algorithm (STA) eliminates the chattering problem encountered in traditional sliding mode control while retaining its robustness properties. The proposed robust tracking controller can guarantee the asymptotic stability of tracking error in …
Harbin Institute of Technology（哈尔滨工业大学）；University of California, Berkeley（加州大学伯克利分校）
The precise motion control of a multi-degree of freedom~(DOF) robot manipulator is always challenging due to its nonlinear dynamics, disturbances, and uncertainties. Because most manipulators are controlled by digital signals, a novel higher-order sliding mode controller in the discrete-time form with time delay estimation is proposed in this paper. The dynamic model of the manipulator used in the design allows proper handling of nonlinearities, uncertainties and disturbances involved in the problem. Specifically, parametric uncertainties and disturbances are handled by the time delay estimati…
Time-delay Control Using a New Nonlinear Adaptive Law for Cable-Driven Robots
Nanjing University of Aeronautics and Astronautics（南京航空航天大学）；Donghai Laboratory（东海实验室）；China Academy of Machinery Beijing Research Institute of Mechanical and Electrical Technology Co., Ltd.（中国机械工业北京机电技术研究院有限公司）
This paper presents an intelligent controller for uncertain underactuated nonlinear systems. The adopted approach is based on sliding mode control and enhanced by an artificial neural network to cope with modeling inaccuracies and external disturbances that can arise. The sliding surfaces are defined as a linear combination of both actuated and unactuated variables. A radial basis function is added to compensate the performance drop when, in order to avoid the chattering phenomenon, the sign function is substituted by a saturation function in the conventional sliding mode controller. An applic…
Ahmadu Bello University（艾哈迈杜·贝洛大学）；Usmanu Danfodiyo University Sokoto（索科托乌斯曼·达福迪奥大学）；Federal Ministry of Power, Works and Housing（联邦电力、工程与住房部）
Chattering phenomena is the major problem affecting sliding mode control (SMC). Also, finding a suitable structure and appropriate parameters values of fuzzy logic system (FLS) is a complex and difficult task. In addition, the stability of a general FLS is difficult to guarantee. Many types of combinations between FLS and SMC have been used to form an intelligent and robust controller that deviates from the limitations of each constituent and benefit from the advantages of each constituent. In this study, a survey of recent developments on the Hybridization of FLS (type-1) and SMC is presented…
This paper proposes a global iterative sliding mode control approach for high-precision contouring tasks of a flexure-linked biaxial gantry system. For such high-precision contouring tasks, it is the typical situation that the involved multi-axis cooperation is one of the most challenging problems. As also would be inevitably encountered, various factors render the multi-axis cooperation rather difficult; such as the strong coupling (which naturally brings nonlinearity) between different axes due to its mechanical structure, the backlash and deadzone caused by the friction, and the difficultie…
