Gantry Crane System Research Articles

A Robust Offline Precomputed Optimal Feedforward Control Action for the Real Time Feedback/Feedforward Control of Double Pendulum Gantry Cranes

This paper deals with FeedBack/ FeedForward (FB/FF) control of double pendulum gantry crane systems with payloads taking values over arbitrarily large intervals. The new proposed 2DoF control architecture is aimed at: 1) to speed up the horizontal payload transportation while minimizing the tracking error with respect to a desired trajectory, 2) to minimize the sway angles amplitude. The main features of the control design procedure are: 1) the dynamic output FB control is designed in order to ensure the robust stability of the closed loop system and the steady-state exact payload positioning; 2) the FF control action is given by the optimally weighted sum of the two contributions due to FF Plant Inversion a (FFPI) and FF Closed Loop Inversion (FFCLI) control schemes; 3) the optimal robust FF control input is obtained as the solution of a min max optimization problem that can be solved offline with numerically efficient procedures; 4) the provided analytical closed form of the FF input in terms of a linear combination of polynomial B-splines basis functions allows an easy implementation on commercial devices.

Power management system for RTG crane using fuzzy logic controller

In this research, there are two major objectives have been investigated for a Rubber Tyred Gantry (RTG) crane system: energy consumption reduction and decrease the stress on the primary source. These objectives can be met by using an advance control system that reads the status of the crane and outputs a power reference value which is fed to the storage device. This paper presents Fuzzy Logic Controller (FLC) approach to maximise the potential benefits of adding energy storage units to RTG cranes. In this work, FLC is described and simulated, with the results analysed to highlight the behaviour of the storage in association with the specific control system. An actual collected data at the Port of Felixstowe, UK has been used to develop the crane and ESS models and test the proposed control strategies in this paper. Furthermore, a comparison analysis between the FLC and the standard control system (PI) for RTG crane and ESS applications will be presented with respect to energy consumption, fuel saving and the control impact on the energy device. The simulation results of the FLC control strategy for the collected data shows that it successfully increases the energy savings by 32% and outperforms the PI controller by 26%.

Experimental Investigation of Fully Informed Particle Swarm Optimization tuned Multi Loop L-PID and NL-PID Controllers for Gantry Crane System

Abstract This paper presents a novel stabilizing nonlinear PID controller with real time experimental validation on a gantry crane system. Our adaptive control technique describes the underactuated system as a nonlinear mapping of control signal with the hyperbolic tangent function. The proposed function is used to impose a constraint on the proportional, integral and derivative errors such that the system results an effective and robust performance. The main trait of the controller is to bound the high control error to result in a lesser correction value. An enhanced hybrid method based on the bioinspired meta-heuristic algorithm Particle Swarm Optimisation is utilised to tune the gain coefficients Kpδ, KIδ and KDδ. The Linear controller and the proposed controllers were compared based on the stabilizing action on the real time system. The real time results depict that the nonlinear PID performs better than the conventional PID.

Optimization of fuzzy logic controller parameters using modern meta-heuristic algorithm for gantry crane system (GCS)

Robust control of underactuated nonlinear systems is a challenging task using conventional methods because of uncertainties which may lead to failure especially for mechanical and robotic applications. Fuzzy logic controller (FLC) is one of the methods specifically used for designing a robust controller that is able to deal with nonlinearity and achieve satisfactory performance for control applications. FLC uses heuristic information or expert operator knowledge to create its mechanism. However, nonlinearities exist in the control systems make its rule-based FLC design a non-trivial task. Manual trial and error tuning method is common way used for tuning the parameters of FLC to achieve the desired performance of the system. Hence, an automatic tuning using optimization algorithm is necessary. Meta-heuristic optimization algorithms are applied to tune the parameters of FLC automatically. In this paper, three popular meta-heuristic algorithms are used to optimize the scaling factors of FLC, i.e. Particle Swarm Optimization (PSO), Cuckoo Search (CS) and Differential Evolution (DE) to improve the effectiveness of FLC design. A gantry crane system, which is a nonlinear system, is used as test system for this project. The simulation of the optimization of FLC parameters by using meta-heuristics algorithms was successfully achieved. The simulation results show that the optimization techniques for FLC are effective to improve the performance of conventional FLC for gantry crane control, i.e. position control and anti-swing control. In addition, PSO performs better than CS and DE in optimization of FLC for gantry crane system.

An Explicit Reference Governor for the Intersection of Concave Constraints

The explicit reference governor (ERG) is a simple and systematic approach that provides constraint handling capabilities to prestabilized systems. The basic idea behind this approach is to translate state and input constraints into an upper-bound on the value of the Lyapunov function, which is then enforced by suitably manipulating the derivative of the applied reference. When designing the ERG, one of the main challenges is the determination of an upper-bound on the value of the Lyapunov function that ensures constraints satisfaction. This paper proposes a systematic approach for estimating online the optimal upper-bound for systems subject to the intersection of concave constraints. To do this, the Barrier function method is used. The effect of the estimation error caused by the time-varying nature of the auxiliary reference on the constraint satisfaction capability of the ERG is studied analytically. A procedure is proposed to modify the estimated upper-bound to avoid constraints violation in the presence of estimation errors. The effectiveness of the proposed scheme is demonstrated through a simulation study on an overhead gantry crane system.

Case Study of Premature Failure of a Concrete Block Pavement System at a Shipping Container Logistics Site

AbstractThe trackway of a high-load gantry crane system at a shipping container logistics site in northern Israel underwent serious premature damages, which jeopardized the continued use of the sys...

Experiments on Motion and Oscillation Controls of a Gantry Crane System Using Parallel Proportional Controllers

The purposes of this research are to formulate the mathematical model of the system, to propose an effective control scheme and to perform experiments on a laboratory scale. The system used in this paper consists of a trolley, a pendulum as load and a dc motor to drive the trolley. Mathematical model of trolley position and load angle were formulated considering voltage of the motor and damping constant of the air calculated specifically using energy balance. Two proportional (P) controllers were designed in parallel in such a way to drive the trolley and to reduce oscillation of the load. The system and the proposed control scheme were confirmed through experiments. The experimental results revealed that the motion and oscillation of the system can be controlled effectively.

Experimental verification of a hybrid control scheme with chaotic whale optimization algorithm for nonlinear gantry crane: A comparative study

This paper proposes an experimental verification of a hybrid partial feedback linearization (PFL) and deadbeat (DB) control scheme as in Hamdy et al. (2018) with chaotic whale optimization algorithm (CWOA) for a nonlinear gantry crane (GC) system. The PFL linearizes the nonlinear model to end up with a linear closed-loop system. The DB controller is utilized for the desirable accelerated response without any oscillation or undesirable effects on the internal dynamics stability. The CWOA is used to tune the controller parameters. A sliding-mode observer (SMO) is utilized to estimate the unmeasured states. Using this hybrid scheme, a better payload sway elimination can be obtained. Finally, the experimental results are presented to illustrate the efficiency and the effectiveness of the proposed scheme with a comparative study.

Proportional–integral-derivative controller with inlet derivative filter fine-tuning of a double-pendulum gantry crane system by a multi-objective genetic algorithm

ABSTRACTOverhead cranes are widely used in industry to move extremely heavy and bulky loads through the overhead space in a facility instead of through aisles or on the floor. Unfortunately, the natural sway of a crane's payload is a huge safety problem which needs more research by control engineers, as the sway of the payload affects both the safety and productivity of a factory. This article introduces an optimized mathematical model of a double-pendulum overhead crane with control schemes: scheme 1 uses three proportional -integral-derivative (PID) controllers with inlet derivative filters; scheme 2 uses one PID controller for accurate trolley positioning and two anti-swing proportional -derivative controllers to eliminate hooks and payload sway, all with inlet derivative filters. The controllers include up to nine gains which are tuned using the multi-objective non-dominated sorting genetic algorithm-II with five fitness functions and weighted function to choose a suitable solution from Pareto solutions.

Vibration Suppression Control of a Flexible Gantry Crane System with Varying Rope Length

The paper presents a control approach to a flexible gantry crane system. From Hamilton’s extended principle the equations of motion that characterized coupled transverse-transverse motions with varying rope length of the gantry is obtained. The equations of motion consist of a system of ordinary and partial differential equations. Lyapunov’s direct method is used to derive the control located at the trolley end that can precisely position the gantry payload and minimize vibrations. The designed control is verified through extensive numerical simulations.

Explicit GPC Control Applied to an Approximated Linearized Crane System

This paper proposes a MIMO Explicit Generalized Predictive Control (EGPC) for minimizing payload oscillation of a Gantry Crane System subject to input and output constraints. In order to control the crane system efficiently, the traditional GPC formulation, based on online Quadratic Programming (QP), is rewritten as a multiparametric quadratic programming problem (mp-QP). An explicit Piecewise Affine (PWA) control law is obtained and holds the same performance as online QP. To test effectiveness, the proposed method is compared with two GPC formulations: one that handle constraints (CGPC) and another that does not handle constraints (UGPC). Results show that both EGPC and CGPC have better performance, reducing the payload swing when compared to UGPC. Also both EGPC and CGPC are able to control the system without constraint violation. When comparing EGPC to CGPC, the first is able to calculate (during time step) the control action faster than the second. The simulations prove that the overall performance of EGPC is superior to the other used formulations.

Visual Servoing of a Flexible Gantry Crane With a Sway Range Constraint

In this letter, the problem of moving a gantry crane with a flexible cable and a sway range constraint to the desired position is solved. The dynamic model of the flexible gantry crane system is built based on the absolute nodal coordinate formulation (ANCF), which is useful for analyzing flexible bodies. A novel controller is proposed to control the gantry crane to the desired position and guarantee the sway range constraint. Moreover, with the help of an eye-in-hand camera, an adaptive law is developed to detect the position of the object with respect to the base frame. The convergence of the cable's position to the desired position, the satisfaction of the sway range constraint, and the convergence of the estimated object's position to the real value are rigorously verified based on the Lyapunov theory. Simulation demonstrates the effectiveness of the proposed controller.

English

English

Dynamic modelling and analysis of 3D overhead gantry crane system

The overhead gantry crane systems are extensively used in harbours and factories for transportation of heavy loads. The crane speeding up, required for motion, always induces undesirable load swing. This writings present dynamic modelling of a 3D overhead gantry crane sys-tem based on closed-form equations of motion. By using the Lagrange technique, a 3D overhead gantry crane system nonlinear dynamic model is deriving. Then perform a linearization process to obtain a linear model dynamic system. Finally, simulation results systems re-sponses of the derived nonlinear and linear model are presented showing the accuracy and performance of both model.

COMPARATIVE STUDY OF MAMDANI AND 1 ST -ORDER TAKAGI SUGENO KANG TYPE FUZZY LOGIC CONTROLLERS FOR CONTROLLING THE RIGID GANTRY CRANE SYSTEM

Controlling the rigid gantry crane system is challenging due to it being an under-actuated system. This paper addresses the challenge by presenting the fuzzy logic controller (FLC) with Mamdani and the 1 st -order Takagi Sugeno Kang (TSK) types presenting it in this comparative study. Both controllers are proposed to control the position of the crane while suppressing the swing of the payload. Simulation results show that the Mamdani type outperforms the 1 st -order Takagi Sugeno Kang (TSK) type in terms of no overshoot, though the earlier controller (Mamdani) has a slower rise time, settling time and peak time than the latter controller (TSK).

Robust Positioning Control Law for a 3D Underactuated Crane System

An existent risk in automated gantry cranes is that the payload, attached to the end of the suspension cable, can swing randomly due to the acceleration of the trolley, by the perturbation of external disturbances, among other unpredictable factors. In this paper, we design second order sliding mode payload position controllers via collocated partial feedback linearization to address such problem. In particular, a super-twisting controller was synthesized to drive the position of the trolley to the desired point, and a twisting controller was derived to stabilize the height of the cable. The proposed sliding surface makes the zero dynamics locally asymptotically stable. We tested the results on an experimental gantry crane system which is affected by matched and mismatched disturbances.

Efficient Generation of Fast Trajectories for Gantry Cranes with Constraints

Time is a crucial factor in the transport business. Besides the duration of the transport itself, also the loading and unloading of the goods is expected to be done as fast as possible to save valuable time and money. Amongst others, this holds true for container ships where the containers are usually loaded and unloaded by means of ship-to-shore gantry cranes. This scenario exemplarily motivates the investigations in this paper. Different methods are proposed for generating a trajectory for the load based on a geometric path connecting the loading and unloading position. As the path is usually just known right before the task has to begin, special emphasis lies on a fast calculation of the trajectory. The overall goal is to traverse the geometric path as fast as possible under the consideration of constraints for the gantry crane system. The optimal solution is calculated and serves as a reference for comparison reasons as the required computing time is usually rather large. Therefore, tailored methods for a fast calculation of the trajectory are developed. All the different approaches are evaluated and compared by means of representative test paths.

NEGATIVE IMAGINARY THEOREM WITH AN APPLICATION TO ROBUST CONTROL OF A CRANE SYSTEM

This paper presents an integral sliding mode (ISM) control for a case of negative imaginary (NI) systems. A gantry crane system (GCS) is considered in this work. ISM is a nonlinear control method introducing significant properties of precision, robustness, stress-free tuning and implementation. The GCS model considered in this work is derived based on the x direction and sway motion of the payload. The GCS is a negative imaginary (NI) system with a single pole at the origin. ISM consist of two blocks; the inner block made up of a pole placement controller (NI controller), designed using linear matrix inequality for robustness and outer block made up of sliding mode control to reject disturbances. The ISM is designed to control position tracking and anti-swing payload motion. The robustness of the control scheme is tested with an input disturbance of a sine wave signal. The simulation results show the effectiveness of the control scheme.

Cooperative control of a nonuniform gantry crane with constrained tension

In this paper, the control problem is addressed for a hybrid PDE–ODE system that describes a nonuniform gantry crane system with constrained tension. A bottom payload hangs from the top gantry by connecting a flexible cable. The flexible cable is nonuniform due to the spatiotemporally varying tension applied to the system. The control objectives are: (i) to position the payload to the desired setpoint, (ii) to regulate the transverse deflection of the flexible cable, and (iii) to keep the tension values remaining in the constrained space. Cooperative control laws are proposed and the integral-barrier Lyapunov functions are employed for stability analysis of the closed-loop system. Adaption laws are developed for handling parametric uncertainties. The bounded stability is guaranteed through rigorous analysis without any simplification of the dynamics. In the end, numerical simulations are displayed to illustrate the performance of the proposed cooperative control.

Closed-Loop Schemes for Position and Sway Control of a Gantry Crane System

This paper presents the investigation into the performance of Lyapunov pole placement (LPP), linear quadratic regulator (LQR) and proportional-integral-derivative (PID) control schemes for payload sway control and trolley position tracking of a gantry crane system. A 2D gantry crane system is considered. The nonlinear model of the system is derived using the Lagrangian energy equation and then linearized using Taylor’s series expansion. To investigate the performances of the designed controllers, a unit step input as a reference perturbation is applied to the controllers. MATLAB simulation results of the responses are analysed in time domain. The response time specifications of the trolley position, level of payload sway reduction, and robustness to parameter variation and uncertainties are used to assess the performances of the controllers.