Control Of Overhead Crane Research Articles

Adaptive sliding mode control of overhead cranes with varying cable length

An overhead crane transports cargoes of various weights and volumes depending on the operation case. Friction factors characterized by damped coefficients are changeable in terms of the operating environment. In this study, an adaptive version of the sliding mode control of a crane system is developed in the case of no priori knowledge of the payload mass and damped elements. Using two inputs, namely, trolley driving force and cargo lifting force, the proposed adaptive robust controller simultaneously executes four duties, including tracking the trolley, hoisting the cargo, keeping the cargo swing small during transient state, and completely eliminating the payload angle at steady destination. Numerical simulations and experiments are conducted to investigate the quality of the proposed controller. The results show that the proposed controller works well and all system responses are asymptotically stabilized.

Parallel neural network combined with sliding mode control in overhead crane control system

A novel control for a nonlinear two-dimensional (2-D) overhead crane is proposed. Instead of the complex design procedures used in classic methods, the proposed scheme combines the principles of neural networks (NNs) and variable structure systems (VSS) to derive control signals needed to drive the cart smoothly, rapidly and with limited payload swing. The merits include the robustness and model-free properties of the sliding mode and neural based controllers, respectively. Simulations performed using a scaled 2-D mathematical model of the crane confirm the effectiveness of the proposed method.

Tracking Control for an Underactuated Two-Dimensional Overhead Crane

In this paper, the tracking control problem is considered for the payload transportation with an underactuated twodimensional overhead crane. Two sliding mode controllers are designed to perform the trajectory tracking. One is proposed to control hoisting and lowering the suspended payload, and the other one is proposed to control both trolley positioning and payload swaying. Considering the second sliding mode controller is used to control two degrees of freedom (DOFs), a fuzzy inference algorithm is proposed to dynamically adjust the coupling factor between the two DOFs. The two controllers make the payload track a predefined trajectory and be safely transported as fast and accurately as possible with a small swing angle, and then place the payload at the desired position. Simulations are performed with the proposed controllers and the results show their effectiveness.

Partial feedback linearization control of overhead cranes with varying cable lengths

Overhead cranes are under-actuated mechanical systems with three degrees-of-freedom (trolley displacement, cable length, and cargo swing angle) and only two actuators: one for cargo hoisting and another for trolley driving. An overhead crane transfers the trolley to a desired position, hoists the cargo up and down until the desired cable length is achieved while keeping the cargo swing angle small during the transfer process. The rope should no longer have a swing angle at the load destination. In this research, a nonlinear controller is proposed for an overhead crane system, in which partial feedback linearization technique is used. To show the effectiveness of the proposed controller, we perform both simulation and experimental study. The simulation and experimental results show that the crane system with the proposed controller is asymptotically stable. Furthermore, all state trajectories of the system reach a steady state within a considerably short time even if the inherent structure of the system is changed.

An Anti-Swing and Positioning Controller for Overhead Cranes Based on Multi-Sliding Mode Method

Overhead cranes are essentially a kind of complex underactuated nonlinear mechanical systems, and it is a challenge to design an anti-swing controller for overhead cranes, hence, many people design controllers of overhead cranes ignoring the changing of the rope length and other parameters. In this study, we propose a multi-sliding mode controller to solve the problem of anti-swing and positioning controller for an overhead crane with rope length variations. This controller can provide a simultaneous trolley-position regulation, sway suppression, and load hoisting control. Also, this paper adopts a new method to decrease the chattering of the control input. Stability analysis of the proposed controller is given in the paper. The proposed controller does not rely on the accurate knowledge of overhead crane system model, and it is simple and easy to apply, and robust to disturbances. The simulation results show the good performance of the proposed controller.

Load’s Damping Swing by Trolley’s Driving Force Control for Overhead or Gantry Crane

In order to obtain the trolley-load system’s dynamic equations for overhead crane or gantry crane, analyzed the dynamic system and deduced the transfer function between the load’s sway angle and the force acting on the trolley from dynamic equations. The force control mode for load’s damping swing is an effective measure of compensation for active anti-swing. Dynamic simulation results show that the optimal evacuation time of the force acting on the trolley is a key parameter that affects the damping swing’s effect. The load’s damping swing effect is favorable when the driving force is withdrawn at optimal withdrawing time; the load’s swing angle’s amplitude will increase with driving force’s increase, but the damping swing effect is still favorable if the optimal withdrawing time is favorably controlled.

Sliding Mode Control of Overhead Crane

We propose a sliding mode load position controller for an overhead crane to cope with large load variations. The controller is developed using the input—output decoupling control laws obtained by the dynamic extension technique. But, due to unknown load mass, it is difficult to design a decoupling control law which exactly cancels out all the nonlinearities. To overcome the problem, we propose a sliding mode controller coupled with the input—output decoupling control law. The simulation results show that the proposed controller performs well under significant load variations.

Open-Loop Control for Overhead Cranes with Load Hoisting by Using Soft Computing

This paper presents a new approach of an open-loop control for overhead cranes with load hoisting to suppress the sway motion after positioning, in which soft computing techniques are utilized. We apply a neural network to generate the desired trolley position. In order to obtain the trajectory of the trolley position to reduce the sway angle as much as possible, the neural network is trained by a particle swarm optimization (PSO). The suppression of the sway angle can be realized by moving the trolley along the obtained trajectory, that is, the open-loop control is established. By performing not only numerical simulations but also experiments, the effectiveness of the proposed method in suppressing the residual sway is demonstrated. In the present approach, it is a feature of the neural network trained by PSO that control systems can be constructed without any prior control knowledge if a mathematical model of a plant is given.

Discrete time integral sliding mode control for overhead crane with uncertainties

This study firstly addresses an integral sliding mode control method for discrete time systems. The underlying continuous system is affected by both matched and unmatched uncertainties. The past value of the disturbance signal is taken as the estimate of its present value. The sliding mode controller is designed to ensure the existence of sliding mode in the presence of uncertainties. The proportional part is designed based on the analysis of closed-loop stability conditions. The controller design theory above is applied to an overhead crane system in later sections. The overhead crane system, which is a familiar control problem is described by a linear model, the parameters of which are estimated. It is affected by uncertainties such as friction, swing of the load and non-linearities because of changing rope length. Both simulation and experimental results are reported. The efficacy and robustness of the proposed controller are demonstrated.

Control of interval parameter overhead cranes via Monte Carlo simulation

Variations in system parameters because of changing operating conditions could result in deteriorated system performance. To ensure robustness, modelling of such systems requires uncertain parameters to be dealt with as interval quantities. An overhead crane is a type of system that has inherent variation in some of its parameters. These parameters include cable length, trolley mass and payload. Hence, the interval parameter concept plays an important role in the control of overhead cranes. This paper considers the control problem of an overhead crane system with interval parameters. The paper presents a new technique based on Monte Carlo simulation to select properly optimal controller parameters. The objective of the control is to minimize the overshoot of the swing angle response throughout the crane travel regardless of the variations of the cable length. The cable length is assumed known within lower and upper bounds. The presented results show the usefulness of the Monte Carlo simulation approach as applied to the control problem of overhead cranes. A scaled-down crane model has been built and used to validate the results of the numerical simulation.

Anti-sway Control for Overhead Cranes with Load Hoisting by Evolutionary Computation

Anti-sway Control for Overhead Cranes with Load Hoisting by Evolutionary Computation

341 ソフトコンピューティングを用いた天井クレーンの振れ止め制御(産業機器の運動と振動の制御,OS-16 運動と振動の制御,総合テーマ「伝統を,未来へ!」)

341 ソフトコンピューティングを用いた天井クレーンの振れ止め制御(産業機器の運動と振動の制御,OS-16 運動と振動の制御,総合テーマ「伝統を,未来へ!」)

2A2-F20 進化計算による巻き上げ機構を有する天井クレーンの振れ止め制御

This paper presents an anti-sway control for overhead cranes with hosting load. The overhead crane involves a planar motion in conjunction with a hosting motion. In order to reduce the sway of the load after positioning, we design the trajectory for the position of the trolley. Neural networks are employed to generate the desired trolley position, and then a particle swarm optimization (PSO) is used for the learning algorithm, in which the maximum swing angle after positioning is adopted as the objective function. The ability of the proposed anti-sway control is confirmed by numerical simulation.

Guaranteed cost control for an overhead crane with practical constraints: Fuzzy descriptor system approach

This study considers a practical overhead crane control problem of designing a fuzzy control to ensure that the trolley arrives precisely at its destination; the load swing angle approaches to zero, and the energy of input and states is minimized. Furthermore, the constraints for the overhead crane operation are also considered and satisfied. Those constraints are that when the crane is moving, the swing angle has to be small; the swing speed has to be slow, and the moving force is limited. The fuzzy descriptor system is chosen to represent the dynamics of the overhead crane, and a guaranteed cost fuzzy control design is proposed for the fuzzy descriptor system. Moreover, this study also illustrates why the fuzzy descriptor system instead of traditional T–S fuzzy system is selected here as the model of the overhead crane. The simulation results demonstrate the effectiveness of the proposed control design scheme.

Robust control for overhead cranes by partial state feedback

This note presents a controller design for overhead cranes that provides robustness with respect to changes in rope length and transported mass. Elsewhere it has been recommended that the rope angular velocity feedback gain should be assigned to zero in linear quadratic (LQ) controller design. In this study, the gain is assigned to zero from another viewpoint, and hence the proposed controller is a partial state feedback controller. The proposed method provides a robust controller design without iterative computations. Simulation results demonstrate the effectiveness of the proposed design.

Optimal control for indoor overhead crane systems with predefined course of crab

Abstract Most papers on optimal control of 3D overhead cranes focus on systems without constraints for the course of the crab (for example [1], [3]). Based on a general 3D model a minimal model with 2 degrees of freedom is developed. Starting from a given initial state the optimal control to reach a given final state is calculated for some predefined courses of the crab. For different turning angles and speeds of the crab an arc of a sine, parabola, circular and an arc of two symmetric clothoid segments have been investigated. Calculations for different values of the mass of the load, turning angles and speed of the crab are presented. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Optimum sway control for overhead traveling cranes

Sway control for industrial applications and for cranes particularly is a historical problem that has accompanied the development in power semiconductors since the 1980's. This article proposes a power semiconductor drive system, which can be used in the anti-sway control of overhead cranes driven three-phase induction motor. The developed system is based on the rotor current control. The proposed power semiconductor drive system is simulated using the developed comprehensive mathematical model. The performance of the proposed systems is analyzed and compared to voltage-controlled anti-sway system. A prototype of the proposed anti-sway control system is developed at the laboratory of electric drives and automation in ATEI - Greece, while the mechanism prototype was developed by the project sponsor - Arab Manufactures Company in Amman - Jordan.

Fast robust control of linear systems subject to actuator saturation

This paper deals with the robust stability of soft variable-structure controls. More precisely, the control of linear plants subject to parametric uncertainty and actuator saturation is considered. Earlier works are summarized and new results are presented in this paper. It is shown that for all considered types of soft variable-structure controls, the robustness analysis leads to parameter-dependent Lyapunov inequalities. An overhead crane control is given as an illustrating example.

고속 권상운동과 흔들림억제 궤적추종을 위한 천정주행 크레인의 퍼지 비선형 적응제어

천정주행 크레인의 고속 권상작업 및 흔들림 억제 궤적추종을 위한 비선형 적응제어 방법을 제시한다. 천정주행 크레인의 흔들림 운동은 트롤리의 가속도. 권상로프의 길이 및 권상속도와 강하게 결합되어 있다. 이는 비간섭 제어 기반의 흔들림 억제 궤적추종 제어법칙을 설계하는데 있어 장애요인으로 작용한다. 이러한 문제를 해결하기 위해, 트롤리의 가속도와 권상속도의 영향을 최소화하는 방법으로 불확실성이 존재하는 경우에도 흔들림 운동의 궁극적 균일 유계성을 보장하는 퍼지 비선형 적응형 흔들림 억제 궤적추종제어법칙을 제안한다. 특히, 제안한 방법은 파라미터 변화. 외란 등을 포함한 시스템 불확실성을 퍼지 불확실성 관측기를 이용하여 보상한다. 따라서, 퍼지관측기의 근사화 오차가 영으로 수렴할 때 추종오차 및 흔들림 각도의 궁극적 한계치는 영으로 감소한다. 끝으로 제안한 방법의 성능검증을 위한 모의실험 견과를 제시한다. Nonlinear adaptive control of overhead cranes is investigated for anti-sway trajectory tracking with high-speed hoisting motion. The sway dynamics of two dimensional underactuated overhead cranes is heavily coupled with the trolley acceleration, hoisting rope length, and the hoisting velocity which is an obstacle in the design of decoupling control based anti-sway trajectory tracking control law To cope with this obstacle. we propose a fuzzy nonlinear adaptive anti-sway trajectory tracking control law guaranteeing the uniform ultimate boundedness of the sway dynamics even in the presence of uncertainties in such a way that it cancels the effect of the trolley acceleration and hoisting velocity on the sway dynamics. In particular. system uncertainties, including system parameter uncertainty unmodelled dynamics, and external disturbances, are compensated in an adaptive manner by utilizing fuzzy uncertainty observers. Accordingly, the ultimate bound of the tracking errors and the sway angle decrease to zero when the fuzzy approximation errors decrease to zero. Finally, numerical simulations are performed to confirm the effectiveness of the proposed scheme.

퍼지 관측기와 퍼지 가변구조제어를 이용한 천정주행 크레인의 적응형 흔들림 억제 궤적추종제어

Adaptive anti-sway and trajectory tracking control of overhead crane is presented, which utilizes Fuzzy Uncertainty Observer(FUO) and Fuzzy based Variable Structure Control(FVSC). We consider an overhead crane system which can be decoupled into the actuated and unactuated subsystems with its own lumped uncertainty such as parameter uncertainties and external disturbance. First, a new method for anti-sway control using FVSC is proposed to improve the conventional method based on Lyapunov direct method, while a conventional trajectory tracking control law using feedback linearization is directly adopted. Second, FUO is designed to estimate one of the two lumped uncertainties which can compensate both of them, based on the fact that two lumped uncertainties are coupled with each other. Then, an adaptive anti-sway control is proposed by incorporating the proposed FVSC and FUO. Under the condition that the observation error is Uniformly Ultimately Bounded(UUB) within an arbitrarily shrinkable region, the overall closed-loop system is shown to be Globally Uniformly Ultimately Bounded(GUUB). In addition, the Global Asymptotic Stability(GAS) of it is shown under the vanishing disturbance assumption. Finally, the effectiveness of the proposed scheme has been confirmed by numerical simulations.