基于趋近律滑模的台车式倒立摆系统控制研究

本文设计了一种基于趋近律方法的滑模控制器。趋近律方法是滑模变结构控制的一种典型控制策略。这种控制方法不仅可以对系统在切换面附近或沿切换面的滑模运动段进行分析,而且可以有效地对系统趋近段的动态过程进行分析和设计,从而保证系统在整个状态空间内具有较好的运动品质。仿真结果表明,将两种典型的趋近律滑模控制方法应用到台车式倒立摆系统中,指数趋近律滑模变结构方法有更好的稳定性和抗干扰能力。     

自平衡机械系统匀速行走模糊控制

针对自平衡机械系统的研究很少着眼于速度控制,设计一种简单的模糊控制器,应用于一级直线倒立摆的匀速行走控制中。对于设定的速度整定值,通过调整几个比例环节的系数,系统具有很好的动态性能指标,而且控制器在有外界扰动时体现了很好的抗扰能力。考虑到实际物理系统中倒立摆行程的限制,设计的自动切换开关实现了倒立摆在一段给定的行程上匀速来回行走的控制目标,通过手动切换开关也能实现倒立摆的位置控制,因而使得该模糊控制器能完成平衡控制、位置控制、匀速行走控制。经多次试验,给出了比例环节系数大小调整与系统动态性能指标之间关系的大致规律,实验结果验证了该控制器的有效性。     

自平衡机械系统匀速行走模糊控制

针对自平衡机械系统的研究很少着眼于速度控制,设计一种简单的模糊控制器,应用于一级直线倒立摆的匀速行走控制中.对于设定的速度整定值,通过调整几个比例环节的系数,系统具有很好的动态性能指标,而且控制器在有外界扰动时体现了很好的抗扰能力.考虑到实际物理系统中倒立摆行程的限制,设计的自动切换开关实现了倒立摆在一段给定的行程上匀速来回行走的控制目标,通过手动切换开关也能实现倒立摆的位置控制,因而使得该模糊控制器能完成平衡控制、位置控制、匀速行走控制.经多次试验,给出了比例环节系数大小调整与系统动态性能指标之间关系的大致规律,实验结果验证了该控制器的有效性.     

基于滑模变结构的柔性倒立摆控制研究

针对柔性倒立摆稳摆控制比较困难且传统指数趋近率的滑模变结构控制易对系统造成抖振,基于机理建模方法建立柔性倒立摆数学模型,提出变指数趋近率的滑模变结构控制方法,设计了滑模变结构控制器,使系统具有较好的稳摆控制和鲁棒性。仿真结果表明,基于变指数趋近率的滑模变结构控制方法能够更好的实现倒立摆稳定控制,相比于传统指数趋近率的滑模控制器输出更加平滑,进而减小了控制器的负担。     

基于阿克曼公式模糊切换增益调节的滑模控制

针对一类具有不确定性和外部干扰的线性系统,基于模糊滑模控制原理,提出了一种基于阿克曼公式模糊切换增益调节的滑模控制器的设计方法;使用了一种新的方法设计滑模面,使系统在趋近切换平面的过程中始终跟踪理想的趋近过程,提高系统的位置跟踪精度;将该方法用于交流伺服控制系统位置控制器的设计,对该控制算法进行了稳定性分析,并进行了建模与仿真;通过选择合理的切换矢量C,使系统在趋近滑模平面的过程中始终跟踪理想的趋近过程,快速到达滑模平面;结果表明系统具有较强的鲁棒性和较快的收敛速度,验证了该方案的有效性.     

一级直线倒立摆匀速行走的模糊控制研究与实现

当前针对倒立摆的研究一般是把角度控制或者位置控制作为控制目标,很少着眼于速度控制,有鉴于此,设计了一种简单的模糊控制器,应用于一级直线倒立摆的匀速行走控制中;仿真实验和实物实时控制实验均验证了该控制器的有效性,对于设定的速度整定值,通过调整几个比例环节的系数,系统具有很好的动态性能指标,而且控制器在有外界扰动时体现了很好的抗扰性;考虑到实际物理系统中倒立摆行程的限制,设计的自动换向开关实现了倒立摆在一段给定的行程上匀速来回行走的控制目标,通过手动切换开关也能实现倒立摆的位置控制。     

模糊趋近率的滑模控制在倒立摆系统中的应用研究

采用Lagrange函数建立了旋转二级倒立摆系统的状态空间方程。为了解决常规滑模控制的抖振问题,提出了一种以极点配置为基础的模糊趋近律滑模控制策略。将模糊逻辑控制与趋近律相结合,推导出模糊趋近律。仿真结果表明,该方法不仅保留了滑模控制系统具有的较强的鲁棒性,同时改善了控制系统滑动模态的品质,消除了系统的抖振。     

二级倒立摆变结构控制改进方案的对比研究

关于二级倒立摆稳定性优化控制问题,二级倒立摆是一个高度非线性系统,具有强耦合和快速运动的特点。但目前采用常规滑动模态变结构控制方法使系统出现高频抖动,导致系统存在稳定性差的问题。采用直线二级倒立摆为被控对象,通过用指数趋近律、边界层法和连续函数的趋近律三种改进方案对二级倒立摆系统进行了仿真,实验效果的对比结果表明,三种方案均能实现对二级倒立摆的稳定性有效控制,并可以使系统抖振得到抑制,为二级倒立摆稳定性设计提供了依据。     

不确定平面二级倒立摆的鲁棒自适应控制

为提高倒立摆控制系统的抗扰动能力,降低其对未建模动态等的敏感度,研究了不确定平面二级倒立摆的鲁棒自适应控制器的设计方法。把倒立摆动力学模型分解为确定和不确定两部分,用一个非线性参数化模糊逻辑系统逼近平面二级倒立摆的不确定动态,采用李雅普诺夫稳定性理论推导出使平面二级倒立摆的状态误差渐近收敛的鲁棒控制器及自适应律。理论分析和仿真结果表明所提出的控制算法是有效的。     

基于积分滑动流形的高阶滑模控制器设计

滑模变结构控制方法因其易实现,鲁棒性强等优点广泛应用于实际控制系统中,讨论了具有积分滑动流形的高阶滑模控制器的设计方法.通过设计含积分滑动流形的高阶滑模面,使系统状态在一阶乃至高阶滑模面上均能达到滑动模态.同时利用高阶滑模面为状态变量设计新的状态空间系统,将原先促使系统状态接近并停留在滑模面上的控制目标,拓展为使高阶滑模状态变量趋近于零的控制目标,并结合最优控制方法来设计等效控制量,利用积分流形设计切换控制的切换面,通过严格证明来证实控制器设计的稳定性.在仿真验证部分采用了一阶倒立摆模型,通过比较常规趋近律滑模控制方法和本文方法的仿真结果,可以得出本文方法在减小系统控制量抖振方面的重要作用和优异效果.     

Sliding mode-like fuzzy logic control with self-tuning the deadzone parameters

In this paper, a fuzzy logic controller (FLC) is designed based on the similarity between the FLC and the sliding mode control (SMC). The proposed scheme provides the sliding mode-like FLC with fast self-tuning the dead-zone parameters (boundary layer thickness) under parameter variations of the controlled system. To show the validity and the effectiveness of the proposed control method, simulations are performed for the position control of a rotary inverted pendulum     

一级倒立摆的滑模模糊变结构控制器设计

一级倒立摆是一个复杂非线性和系统。本文针对系统本身存在许多准确建模的因素,设计了基于滑模的模糊变结构控制器。仿真结果表明该控制系统对于外部扰动和参数摄动具有良好的鲁棒性。     

Fuzzy sliding mode control for a robot manipulator

This work presents the design of a robust control system using a sliding mode controller that incorporates a fuzzy control scheme. The presented control law superposes a sliding mode controller and a fuzzy logic controller. A fuzzy tuning scheme is employed to improve the performance of the control system. The proposed fuzzy sliding mode control (FSMC) scheme utilizes the complementary cooperation of the traditional sliding mode control (SMC) and the fuzzy logic control (FLC). In other words, the proposed control scheme has the advantages which it can guarantee the stability in the sense of Lyapunov function theory and can ameliorate the tracking errors, compared with the FLC and SMC, respectively. Simulation results for the trajectory tracking control of a two-link robot manipulator are presented to show the feasibility and robustness of the proposed control scheme. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

FUZZY SLIDING MODE CONTROLLER DESIGN: INDIRECT ADAPTIVE APPROACH

In this paper, using the concept of sliding mode control SMC, a fuzzy sliding mode controller FSMC, which is synthesized by linguistic control rules, is proposed. Two sets of fuzzy rule bases are utilized to represent the controlled system. The membership functions of the THEN-part, which is used to construct a suitable equivalent control of SMC, are changed according to adaptive law. In particular, only one adaptive factor is characterized to adapt the membership functions instead of several ones in conventional adaptive approaches. Under this design scheme, we not only maintain the distribution of membership functions over state space but also reduce considerably computing time. The proposed indirect adaptive FSMC is synthesized through the following stages. First, we construct the fuzzy rule bases according to the common sense of SMC to describe the model of the controlled system, and define the fuzzy sets whose membership functions are equally distributed in state space. Then, the derived adaptive law is used to adjust the membership functions of the THEN-part to approximate an equivalent control without knowing the mathematical model of the controlled system. Third, a hitting control is developed to guarantee the stability of the control system. Finally, we smooth the hitting control via proposed heuristic control rules. We apply this FSMC to controlling a nonlinear inverted pendulum system to confirm the validity of the proposed approach.     

A third-order sliding mode controller for nonlinear multivariable systems

This paper proposes a third-order sliding mode controller for nonlinear multivariable systems with uncertain parameters and subject to external disturbances. The controller achieves fast convergence rate, high tracking accuracy, and a reduced level of chattering. The stability of the controller and its global ultimately uniform convergence is proved by the Lyapunov stability theory. Simulation results on a single inverted pendulum system are given to illustrate the effectiveness of the proposed control scheme by comparing it with methods such as a second-order supertwisting controller, a third-order supertwisting controller, and an integral terminal third-order sliding mode controller.     

A neuro-fuzzy-sliding mode controller using nonlinear sliding surface applied to the coupled tanks system

The aim of this paper is to develop a neuro-fuzzy-sliding mode controller （NFSMC） with a nonlinear sliding surface for a coupled tank system. The main purpose is to eliminate the chattering phenomenon and to overcome the problem of the equivalent control computation. A first-order nonlinear sliding surface is presented, on which the developed sliding mode controller （SMC） is based. Mathematical proof for the stability and convergence of the system is presented. In order to reduce the chattering in SMC, a fixed boundary layer around the switch surface is used. Within the boundary layer, where the fuzzy logic control is applied, the chattering phenomenon, which is inherent in a sliding mode control, is avoided by smoothing the switch signal. Outside the boundary, the sliding mode control is applied to drive the system states into the boundary layer. Moreover, to compute the equivalent controller, a feed-forward neural network （NN） is used. The weights of the net are updated such that the corrective control term of the NFSMC goes to zero. Then, this NN also alleviates the chattering phenomenon because a big gain in the corrective control term produces a more serious chattering than a small gain. Experimental studies carried out on a coupled tank system indicate that the proposed approach is good for control applications.     

Design of interval type-2 fuzzy sliding-mode controller

In this paper, an interval type-2 fuzzy sliding-mode controller (IT2FSMC) is proposed for linear and nonlinear systems. The proposed IT2FSMC is a combination of the interval type-2 fuzzy logic control (IT2FLC) and the sliding-mode control (SMC) which inherits the benefits of these two methods. The objective of the controller is to allow the system to move to the sliding surface and remain in on it so as to ensure the asymptotic stability of the closed-loop system. The Lyapunov stability method is adopted to verify the stability of the interval type-2 fuzzy sliding-mode controller system. The design procedure of the IT2FSMC is explored in detail. A typical second order linear interval system with 50% parameter variations, an inverted pendulum with variation of pole characteristics, and a Duffing forced oscillation with uncertainty and disturbance are adopted to illustrate the validity of the proposed method. The simulation results show that the IT2FSMC achieves the best tracking performance in comparison with the type-1 Fuzzy logic controller (T1FLC), the IT2FLC, and the type-1 fuzzy sliding-mode controller (T1FSMC).     

Fuzzy control stabilization with applications to motorcycle control

This study develops fuzzy control that is designed with sliding modes to achieve stability of the fuzzy controller. Fuzzy control is formulated in the form of variable structure system (VSS) control. In contrast to previous works in which Lyapunov functions are used to examine the stability, the current study investigates the stability of fuzzy control from the viewpoints of differential geometric methods and the sliding mode theory. Best values for parameters in fuzzy control rules are determined with the aid of sliding modes. In order to improve control performance, a tuning algorithm is executed to adjust parameters for dealing with uncertainties and disturbances. Both computer simulations and experiments with regard to an inverted pendulum hinged to a rotating disk are carried out to validate the proposed method. This apparatus can to some extent represent cornering motion of a motorcycle on which a rider leans to maintain stability. Effects of rider's leaning angle on both stability and handling control are examined according to Bode plots.     

二级直线倒立摆系统的实物控制

针对二级直线倒立摆系统,采用拉格朗日方程法建立其理论模型,分别使用线性二次最优控制（Linear Quadratic Regulator,LQR）及基于趋近律的滑模控制（Sliding Mode Control,SMC）算法来实现干扰存在情况下倒立摆的平衡控制。对于LQR算法,研究了矩阵[Q]和矩阵[R]与反馈控制矩阵[K]的定性关系,并经过反复多次实验,不断试凑,得到一组良好的控制参数,实现了倒立摆的稳定控制。SMC算法采用基于指数趋近律的控制方法进行了滑模变结构控制器的设计,并利用边界层法来进一步削弱抖振。最后通过仿真及实验,实现了倒立摆的实物平衡控制。