Showing papers on "Sliding mode control published in 1994"
TL;DR: A robust MIMO terminal sliding mode technique and a few structural properties of rigid robotic manipulators are developed so that the output tracking error can converge to zero in a finite time, and strong robustness with respect to large uncertain dynamics can be guaranteed.
Abstract: In this paper, a robust multi-input/multi-output (MIMO) terminal sliding mode control technique is developed for n-link rigid robotic manipulators. It is shown that an MIMO terminal switching plane variable vector is first defined, and the relationship between the terminal switching plane variable vector and system error dynamics is established. By using the MIMO terminal sliding mode technique and a few structural properties of rigid robotic manipulators, a robust controller can then be designed so that the output tracking error can converge to zero in a finite time, and strong robustness with respect to large uncertain dynamics can be guaranteed. It is also shown that the high gain of the terminal sliding mode controllers can be significantly reduced with respect to the one of the linear sliding mode controller where the sampling interval is nonzero. >
853 citations
14 Dec 1994
TL;DR: In this article, a Lyapunov function yielding a stable switching rule is shown to exist as long as there exists a stable convex combination of the system matrices, and the use of this stable combination for other control strategies is explored.
Abstract: This paper discusses the problem of stabilizing a pair of switched linear systems. A control law is developed using a Lyapunov function having a piecewise continuous derivative. A Lyapunov function yielding a stable switching rule is shown to exist as long as there exists a stable convex combination of the system matrices. The use of this stable combination for other control strategies is explored. >
344 citations
Book•
01 Feb 1994
TL;DR: An algebraic approach to sliding mode variable structure control (VSC) is presented in this paper, where robust tracking with a sliding mode and robust tracking in discrete-time and difference systems are presented.
Abstract: An introduction to sliding mode variable structure control.- An algebraic approach to sliding mode control.- Robust tracking with a sliding mode.- Sliding surface design in the frequency domain.- Sliding mode control in discrete-time and difference systems.- Generalized sliding modes for manifold control of distributed parameter systems.- Digital variable structure control with pseudo-sliding modes.- Robust observer-controller design for linear systems.- Robust stability analysis and controller design with quadratic Lyapunov functions.- Universal controllers: Nonlinear feedback and adaptation.- Lyapunov stabilization of a class of uncertain affine control systems.- The role of morse-Lyapunov functions in the design of nonlinear global feedback dynamics.- Polytopic coverings and robust stability analysis via Lyapunov quadratic forms.- Model-following VSC using an input-output approach.- Combined adaptive and Variable Structure Control.- Variable structure control of nonlinear systems: Experimental case studies.- Applications of VSC in motion control systems.- VSC synthesis of industrial robots.
299 citations
TL;DR: The performance and the robustness of this kind of FC stems from their property of driving the system into the sliding mode (SM), in which the controlled system is invariant to parameter fluctuations and disturbances.
295 citations
TL;DR: A time-varying sliding surface for a variable structure control (VSC) law is proposed to achieve fast and robust tracking in a class of second-order uncertain dynamic systems.
229 citations
20 Jun 1994
TL;DR: In this article, a method for the estimation of changes in stator resistance during the operation of the induction machine is presented, which is implemented using proportional integral control and fuzzy logic control schemes.
Abstract: Direct torque control (DTC) of induction machines uses the stator resistance of the machine for estimation of the stator flux. Variations of stator resistance due to changes in temperature or frequency make the operation of DTC difficult at low speeds. A method for the estimation of changes in stator resistance during the operation of the machine is presented. The estimation method is implemented using proportional-integral (PI) control and fuzzy logic control schemes. The estimators observe the machine stator current vector to detect the changes in stator resistance. The performance of the two methods are compared using simulation and experimental results. Results obtained have shown improvement in DTC at low speeds.
187 citations
TL;DR: Since in sliding mode control, the states remain on the sliding surface, the motion of the piston is very smooth, suggesting the potential of pneumatic cylinders as actuators for robot manipulators.
Abstract: A new position control algorithm, based on sliding mode control, has been developed for a pneumatic cylinder. In the proposed pneumatic system, commercially available two-way on-off solenoid valves have been used. The inherent robustness property of the sliding mode controller makes it easier to select the switching gains of the controller. Moreover, approximate dynamic modeling of the system makes the controller simple. Since in sliding mode control, the states remain on the sliding surface, the motion of the piston is very smooth. This suggests the potential of pneumatic cylinders as actuators for robot manipulators. The controller is hybrid in nature, consisting of an error amplifier, data conversion devices and an 8088 microprocessor along with various digital circuit accessories. Only one feedback device (potentiometer) is used. Velocity is calculated from the sampled position signals. >
166 citations
02 Oct 1994
TL;DR: In this paper, a grey prediction model combined with a proportional plus derivative controller is proposed to balance an inverted pendulum, which is a classic example of an inherently nonlinear unstable system.
Abstract: A system with partial unknown structure, parameters, and characteristics is called a grey system. The grey theory can be employed to improve the control performance of a system without sufficient information or with highly nonlinear property. In this paper, a grey prediction model combined with a proportional plus derivative controller is proposed to balance an inverted pendulum, which is a classic example of an inherently nonlinear unstable system. The control objective is to swing up the pendulum from a stable position to an unstable position and bring its slider back to the origin of the track. The overall control algorithm is decomposed into two separate grey model controllers for swinging up and balancing, respectively, based upon the angular and velocity values of the pendulum. The experimental results show that this grey model controller is able to swing up and balance the inverted pendulum and guide its slider to the center of the track. It also has the robustness to balance the inverted pendulum at an upright position in suffering an external impact acting on the pendulum.
163 citations
02 Oct 1994
TL;DR: In this article, the authors presented a systematic approach to small-signal modeling and control design of three-phase PWM converters, where the well established design procedures used in DC-DC converter control design, are adapted for the threephase converter control based on the similarity in the small signal dynamics of the 3-phase converters and their DCDC counterparts.
Abstract: The paper presents a systematic approach to small-signal modeling, and control design of three-phase PWM converters. The well established design procedures used in DC-DC converter control design, are adapted for the three-phase converter control based on the similarity in the small-signal dynamics of the three-phase converters and their DC-DC counterparts. The approach is especially beneficial in three-phase rectifier control, which is reduced to a single-input single-output system after closing the current loops. The modeling approach is verified on a 10 kW three-phase boost rectifier switching at 15.6 kHz with DSP control. A wide-bandwidth output voltage control loop is then designed based on the verified small-signal transfer functions. >
156 citations
01 Jan 1994
TL;DR: Wide use of digital controllers has placed onto the research agenda the generalization of sliding mode control methodology to discrete-time control systems.
Abstract: Wide use of digital controllers has placed onto the research agenda the generalization of sliding mode control methodology to discrete-time control systems. In the first studies, control algorithms intended for continuous- time systems were applied to discrete-time problems; resulting in chattering since the switching frequency can not exceed that of sampling. Then methods for reducing chattering were developed in many publications.
151 citations
TL;DR: In this paper, a nonlinear sliding surface with suitable stabilizing properties is synthesized on the basis of the extension of a linear sliding design carried out for the parametrized average linear incremental model of the converter.
Abstract: The method of extended linearization is proposed for the systematic solution of sliding mode controller design in DC-to-DC power converters of the boost and the buck-boost type. A nonlinear sliding surface with suitable stabilizing properties is synthesized on the basis of the extension of a linear sliding design carried out for the parametrized average linear incremental model of the converter. The obtained feedback strategies lead to asymptotically stable sliding modes with remarkable self-scheduling properties. Simulation examples are presented for illustrative purposes. >
27 Jun 1994
TL;DR: For a class of single-input, single-output, continuous-time nonlinear systems, a neural network-based controller is presented that feedback linearizes the system and a global stability proof is given in the sense of Lyapunov.
Abstract: For a class of single-input, single-output (SISO), continuous-time nonlinear systems, a neural network-based controller is presented that feedback linearizes the system. Control action is used to achieve tracking performance for a state-feedback linearizable, but unknown nonlinear system. A global stability proof is given in the sense of Lyapunov. It is shown that all the signals in the closed-loop system and the control action are GUUB. No learning phase requirement is needed and initialisation of the network is straightforward. >
14 Dec 1994
TL;DR: An approach based on sliding mode control is used to design a feedback which stabilizes the origin for a class of nonlinear driftless systems of the form x/spl dot/=B(x)u.
Abstract: Uses an approach based on sliding mode control to design a feedback which stabilizes the origin for a class of nonlinear driftless systems of the form x/spl dot/=B(x)u. introduced by Brockett (1993). Brockett showed that these systems fail his necessary condition for the existence of smooth feedback. >
29 Jun 1994
TL;DR: In this paper, a systematic way to combine an adaptive control design technique and sliding mode control methodology for trajectory tracking control of robot manipulators in the presence of parametric uncertainties and external disturbance is developed.
Abstract: A systematic way to combine an adaptive control design technique and sliding mode control methodology for trajectory tracking control of robot manipulators in the presence of parametric uncertainties and external disturbance is developed in this paper. Continuous sliding mode controllers without the unpleasant reaching transient and chattering problem are first developed by using a dynamic sliding mode. Transient performance is guaranteed and globally uniform ultimate boundedness (GUUB) stability is obtained. A conventional adaptive scheme is also developed for comparison. With some modifications to the conventional adaptation law, the control law is redesigned by combining the design methodologies of adaptive control and sliding mode control. The suggested controller preserves the advantages of both methods, namely, asymptotic stability of adaptive systems for parametric uncertainties and GUUB stability with guaranteed transient performance of sliding mode control for both parametric uncertainties and external disturbances. The control law is continuous and the chattering problem of sliding mode control is avoided. A priori knowledge of the bounds of the parameter uncertainties and external disturbances is assumed. Experimental results illustrate the effectiveness of the proposed methods.
14 Dec 1994
TL;DR: The mobile robot is shown to be exponentially stabilizable for a class of quadratic Lyapunov functions and ideal tracking of the prescribed trajectories is achieved by exploiting the invariance property and the order reduction property of sliding mode control.
Abstract: Mobile robots with non-holonomic kinematics have three degrees of freedom for planar motion, but there are only two control inputs available. The stabilization problem for such robots is known not to be solvable via smooth time-invariant feedback. The authors propose to utilize a Lyapunov function to prescribe a set of desired trajectories to navigate the robot to a specified configuration. Ideal tracking of the prescribed trajectories is achieved by exploiting the invariance property and the order reduction property of sliding mode control. The mobile robot is shown to be exponentially stabilizable for a class of quadratic Lyapunov functions. >
01 Jan 1994
TL;DR: In this paper, a dynamical multivariable discontinuous feedback control strategy of the sliding mode type was proposed for the altitude stabilisation of a nonlinear helicopter model in vertical flight.
Abstract: A dynamical multivariable discontinuous feedback control strategy of the sliding mode type is proposed for the altitude stabilisation of a nonlinear helicopter model in vertical flight. While retaining the basic robustness features associated with sliding mode control policies, the proposed approach also results in smoothed out (i.e. nonchattering) input trajectories and controlled state variable responses.
29 Jun 1994
TL;DR: In this paper, a feedback control law is derived that causes a nonlinear, nonholonomic, nonminimum phase model of a riderless powered two-wheeled bicycle to stably track arbitrary smooth trajectories of roll-angle and nonzero rear-wheel velocity.
Abstract: A feedback control law is derived that causes a nonlinear, nonholonomic, nonminimum phase model of a riderless powered two-wheeled bicycle to stably track arbitrary smooth trajectories of roll-angle and non-zero rear-wheel velocity.
14 Dec 1994
TL;DR: In this article, a control strategy for nonholonomic systems using the time-state control form is proposed, which allows the non-holonomic system which cannot be transformed to a chained form.
Abstract: In this paper, we propose a control strategy for nonholonomic systems using the time-state control form. This approach allows us to control nonholonomic systems which cannot be transformed to chained form. We apply this control strategy to the position control of multitrailer systems. >
TL;DR: This paper proposes two fuzzy rule based algorithms for smoothing the control input of a variable structure system (VSS) based on a semiactive suspension system based on optimal control and a direct drive robot arm under discrete time sliding mode control.
Abstract: A variable structure system (VSS) is a control system implementing different control laws in different regions of the state space divided by a set of boundary manifolds. The control input switches from one control law to another when the state crosses the boundary manifolds. In general, the control input may not be smooth when switching at these boundary manifolds and may excite high frequency dynamics. This paper proposes two fuzzy rule based algorithms for smoothing the control input. The merits of these fuzzy smoothing control algorithms are illustrated by two examples: a semiactive suspension system based on optimal control and a direct drive robot arm under discrete time sliding mode control. The controller design for these two examples is a blend of traditional control theoretic approaches and fuzzy rule based approaches. >
29 Jun 1994
TL;DR: In this article, a vehicle is controlled to follow the virtual desired trajectory using only on-board sensors, assuming no direct measurement of its position during transition from one lane to another.
Abstract: A lane change maneuver is a part of lateral control of an automated highway system. Assuming no direct measurement of its position during transition from one lane to another, a vehicle is controlled to follow the virtual desired trajectory using only on-board sensors. Linear quadratic (LQ), frequency shaped LQ, and sliding mode control algorithms have been designed. The simulation results show satisfactory tracking performances under extreme driving conditions.
Journal Article•
TL;DR: In this paper, the authors investigated the lane change maneuver for an automated highway system as a tracking problem with respect to the virtual desired trajectory (VDT), and three closed loop controllers based on linear quadratic (LC) optimal control, frequency shaped linear quadric (FSLQ), and sliding mode control were evaluated.
Abstract: In this report, lane change maneuver for an automated highway system is investigated as a tracking problem with respect to the virtual desired trajectory (VDT). The two main issues discussed in the report are: 1) design of virtual desired trajectory and 2) design of control algorithms. Four types of desired trajectories are considered. The use of onboard sensors for closed loop control are used. Three closed loop controllers, based on 1) linear quadratic (LC) optimal control, 2) frequency shaped linear quadratic (FSLQ), and 3) sliding mode control are evaluated. Simulation results show that these controllers provide acceptable performance in the presence of uncertainties and disturbances.
TL;DR: In this article, a PWM rectifier including an uncontrolled rectifier and a Cuk converter stage driven by a sliding mode controller is described, which allows low-distorted and in-phase line current.
Abstract: A PWM rectifier including an uncontrolled rectifier and a Cuk converter stage driven by a sliding mode controller is described. Like other high-quality rectifiers, this solution allows low-distorted and in-phase line current. Moreover, due to the sliding mode control, fast and stable response is achieved, in spite of the large output filter. Control complexity is the same as that of standard current-mode controls. Converter analysis, design criteria, and experimental results are reported. >
TL;DR: Various control schemes for a single flexible robot arm are considered and a conclusive, although partial, comparison for this kind of single axis robot is embodied.
Abstract: Various control schemes for a single flexible robot arm are considered in this paper. They require a limited amount of on-line computations. All trials are performed on the physical process and embody a conclusive, although partial, comparison for this kind of single axis robot. They are representative of some major applied research directions which captured the attention of many researchers throughout the 1980's. Some general conclusions are derived. >
29 Jun 1994
TL;DR: Active variable stiffness (AVS) systems have been demonstrated to be effective in response control of buildings subjected to earthquake excitations based on the theory of variable structure system (VSS) or sliding mode control (SMC).
Abstract: Active variable stiffness (AVS) systems have been demonstrated to be effective in response control of buildings subjected to earthquake excitations Based on the theory of variable structure system (VSS) or sliding mode control (SMC), control methods for applications of AVS systems to seismic-excited buildings are presented In addition to full-state feedback controllers, general static output feedback controllers as well as special output feedback controllers using only collocated sensors are also presented Simulation results demonstrate that the performance of the control methods presented is remarkable, and that the performance of output feedback controllers is comparable to that of the full-state feedback controllers
29 Jun 1994
TL;DR: It is shown that good tracking of a reference path, delineated either continuously or discretely, can be achieved with a minimum effort in sensing and without preview of the road curvature.
Abstract: Highway automation is a promising approach to cope with increasing road traffic and congestions An important control subtask of an intelligent vehicle/highway system is automatic steering for lateral vehicle control Due to system uncertainties and the wide range of operating conditions, state-of-the-art robust control techniques are required This paper introduces two automatic steering controllers for cars driving under highway conditions The control design is based on sliding mode control and robust state observation It is shown that good tracking of a reference path, delineated either continuously or discretely, can be achieved with a minimum effort in sensing and without preview of the road curvature
05 Sep 1994
TL;DR: In this paper, a sliding mode based design method was developed for control of manipulators, mobile robots operating in workspace with obstacles, railway wheelset and flexible shaft, based on utilizing a state subvector as an intermediate control.
Abstract: Sliding mode based design methods are developed for control of manipulators, mobile robots operating in workspace with obstacles, railway wheelset and flexible shaft. The core design idea rests upon utilizing a state subvector as an intermediate control. >
TL;DR: This note designs a simple sliding mode control for a single input discrete-time VSS such that not only the discrete- time uncertain system is stabilized robustly, but also the chattering along the sliding mode is reduced explicitly.
Abstract: The main differences between the designs of discrete-time variable structure systems (VSS) and continuous-time VSS are the determination of the switching hyperplane and the satisfaction of the hitting/sliding condition. These differences yield many difficulties in the design of sliding mode control for the discrete-time VSS. This note tries to overcome these difficulties and design a simple sliding mode control for a single input discrete-time VSS such that not only the discrete-time uncertain system is stabilized robustly, but also the chattering along the sliding mode is reduced explicitly. Instead of the conventional switching hyperplane, in the discrete-time case a "switching region", which includes the hyperplane S/sub 0/ and its neighborhood, is determined and used. The determination of the switching region is to locate the equilibrium point of the nominal subsystem on each hyperplane S/sub p/ outside the switching region such that the state motions inside and outside the switching region will occur alternately until the state of the closed-loop system reaches the origin. Moreover, we prove that the robustness property is retained whenever the uncertainty satisfies a standard matching condition. >
02 Oct 1994
TL;DR: In this article, a second order sliding mode observer is proposed for state estimation in a switched reluctance machine (SRM) and the estimated rotor position obtained from the observer is used for the electronic commutation of the machine phases.
Abstract: In this paper a second order sliding mode observer is proposed for state estimation in a switched reluctance machine (SRM). The estimated rotor position obtained from the observer is used for the electronic commutation of the machine phases. The proposed sliding mode observer provides a robust method of indirect rotor position sensing using terminal measurements of phase voltage and currents. The paper includes detailed simulations of a closed loop controller based on the proposed sliding mode observer. >
26 Jun 1994
TL;DR: By applying the AFSMC to control a nonlinear unstable inverted pendulum system, the simulation results showed the expected approximation sliding property, and the dynamic behavior of control system can be determined by the sliding surface.
Abstract: An adaptive fuzzy sliding mode controller (AFSMC) is proposed. The parameters of the membership functions in the fuzzy rule base are changed according to some adaptive algorithm for the purpose of controlling the system state to hit a user-defined sliding surface and then slide along it. The initial IF-THEN rules in the AFSMC can be randomly selected or roughly given by human experts, and then automatically tuned by a direct adaptive law. Therefore, the reduction of the expertise dependency in the design procedure of fuzzy logic control is called the rule tolerance property. By applying the AFSMC to control a nonlinear unstable inverted pendulum system, the simulation results showed the expected approximation sliding property, and the dynamic behavior of control system can be determined by the sliding surface. >
05 Sep 1994
TL;DR: In this article, a sliding mode controller for a single phase inverter used in UPS applications is presented, where the use of a reduced order observer eliminates the requirement of the load current measurement and improves the noise immunity.
Abstract: This paper deals with a sliding mode controller for a single phase inverter used in UPS applications. The proposed system provides overload and short circuit protection. It can operate in constant or variable frequency. The use of a reduced order observer eliminates the requirement of the load current measurement and improves the noise immunity. Experimental results obtained in laboratory are presented and they confirm the simulation and theoretical analysis. >