Overhead Crane Research Articles

Experience of the examination of industrial safety of structuresof the open flyover of the slag yard of the open-hearth workshop of JSC TAGMET

Industrial safety expertise plays a huge role in preserving buildings and structures and preventing their destruction and undesirable consequences that are inevitable during the operation of damaged structures, especially in buildings with hazardous production or under heavy operating conditions of overhead cranes. Currently, due to the aging and wear of structures, the examination of industrial safety of buildings and structures is becoming increasingly important. Central Research Institute of Building Structures named after V.A. Koucherenko of JSC "SIC "Construction" since 1995 for almost 20 years conducted surveys of the workshops of JSC "Tagmet", giving conclusions on industrial safety and recommendations for repairing and strengthening damaged building structures in order to enable and conditions for further safe operation. The article provides an example of successfully carried out work on the inspection of shop structures, which can be extended to modern practice. The article analyzes the results of a survey of the technical condition of structures, classifies damages and gives recommendations for ensuring the safe operation of structures of an open crane overpass.

Damping of oscillations of load lifted by handling equipment

This work is aimed at improving the performance of various handling equipment by optimizing the transportation cycle, e.g., decreasing the time of acceleration and deceleration by damping load oscillations, increasing the steady-state motion speed, and decreasing the time of pauses. The object of modeling is an overhead crane with a capacity of 15 ton, a stroke of 15 m, and three degrees of freedom. A Lagrange equation of the first kind as a non-linear heterogeneous system was used. A mathematical analysis of the damping process was carried out by energy balance modeling. As a result, the optimal amplitude and frequency of damping impulses required to change the suspension length within 5% were obtained. These impulses have a maximum frequency of three oscillations per second and are supplied in a reversed phase to load oscillations. According to calculations, energy costs for damping load oscillations are below 3–4% of the lifting motor power. It is shown how damping is implemented in manual control, and coefficients are calculated to define the amplitude of changes in the load and arm suspension length. The ranges of changes in these coefficients comprise 0.85–0.9 and 1.1–1.15 for setting the amplitude and frequency of damping impulses when using an automatic system. On this basis, a load oscillation damping system for a moving overhead crane is developed. Options are proposed for the damping system: by an operator or an automatic control system. The mathematical model of a crane is suitable for studying various types of equipment. Due its high efficiency and relatively low cost, the proposed method of damping is recommended when designing new equipment or improving the existing equipment.

Prediction System for Overhead Cranes Based on Digital Twin Technology

To solve the problems of inaccurate quality inspection and poor safety maintenance of traditional overhead cranes, this study has developed a prediction system for overhead cranes based on digital twin technology. First, interworking of the data flow between the control port of the overhead crane and the digital twin system is realized. Then, finite element technology is exploited to calculate the stress of the crane bridge, thereby performing stress rendering of the digital twin system. Next, the life of bridge cranes is predicted by the stress and strain of their main girders. Finally, synchronous overhead-crane communication combines the virtual twin system and the actual control system of the crane. The study results provide a reference for developing crane software based on digital twins.

Input-limited optimal control for overhead cranes with payload hoisting/lowering and double pendulum effects

Input-limited optimal control for overhead cranes with payload hoisting/lowering and double pendulum effects

Seismic Performance Assessment of a Moment-Resisting Frame Steel Warehouse Provided with Overhead Crane

The purpose of this study is to analyze the nonlinear behavior of a steel warehouse structured by moment-resistant frames, which utilizes an overhead crane on its interior brackets and as an external load of the weight of the lining panels. The analysis methods used are (i) pushover analysis, which consists of applying an incremental force in the transverse and longitudinal direction to obtain the capacity curve of the structure; (ii) time-history analysis, in which different records of destructive earthquakes that occurred in Chile are used in order to analyze the response of the structure to these loads. The results indicate that the transverse direction is more ductile than the Y direction of the structure within the pushover and time-history methods but not using the N2 method. It is also found that most of the columns are within the life safety and collapse prevention criteria. It is concluded that most of the analyses agree with each other and with what is expected, except for the N2 method, which contradicts the results of the time-history analysis, so the N2 method would not be suitable for this type of structure. In addition, it has been determined that the overhead crane loads do not substantially affect the seismic performance of the warehouse.

An improved approach for model predictive control in 3-D overhead crane systems

An improved approach for model predictive control in 3-D overhead crane systems

A concepts and techniques related to the DC motor speed control system design: Systematic Review

The first sources of direct current (DC) were invented, DC machines were one of the first types of electro-mechanical machines used. DC machines are more advantageous over AC machines as regards to Speed regulation and versatility. A DC motor is an electrical actuator with a lot of control that is used in a lot of applications, like robotic manipulators, guided vehicles, steel rolling mills, cutting tools, overhead cranes, electrical traction, and other applications. Due to their speed-torque characteristics and ease of control, DC motors are utilized extensively in industries for demanding variable speed applications. In terms of controller design and implementation, the process control industry has seen numerous advancements over the past two decades. In the industry, there is a great demand for automatic controllers that can respond quickly and accurately to perform precise tasks. The feedback loop is an essential component of system control that must be utilized in order to achieve the desired performance in the majority of systems. Numerous control strategies have been developed for various feedback control systems in order to achieve rapid system dynamic response. Controls in a drive system are crucial if the reference speed is to be accurately and quickly tracked, with little or no steady-state error and as little overshoot as possible. This paper presents the Systematic literature review that was conducted as covers pertinent established concepts and techniques related to the DC motor speed control system design, for applications that require actuators with accurate speed characteristics. Simulation and real time implementation results employed for DC motor speed control systems in various literature are analysed and discussed.

Экспериментальное исследование деформированного состояния металлоконструкций грузовых тележек кранов мостового типа с универсальной компоновочной схемой

Deformations of the supporting metal structures of machines for various purposes have a significant impact on the performance of the equipment installed on them. Insufficient rigidity of a metal structure can cause jamming and failure of drive elements and working bodies of material handling, construction and road machines, the operation of which is associated with the impact of high static and dynamic loads. Therefore, when designing new structural schemes of load-bearing metal structures, special attention must be paid to the issue of ensuring the necessary rigidity. The presented work contains the results of an experimental assessment of the deformed state of physical models of the metal structures of load trolleys of overhead cranes, made on the basis of a multipurpose layout drawing using various types of connections of bearing elements. The article reflects information about the methodology of experimental research, describes the features of the physical models of metal structures used in the course of the experiment. The data on the vertical displacements of the control points of metal structures when using various loading schemes are given. An assessment was made of the influence of the type of applied connections of load-bearing elements on the features of the resulting deformed state of the metal structure. A comparative analysis of experimental data and calculated values of vertical displacements of points of metal structures obtained as a result of computer simulation of the formed state using various finite element models is performed.

An active swing suppression control scheme of overhead cranes based on input shaping model predictive control

An input shaper-based model predictive control scheme is proposed for an overhead crane to suppress the swing of the payload. A control-oriented mathematical model of the crane is firstly derived based on the small angle hypothesis. Furthermore, three kinds of commonly used shapers are discussed and a zero vibration derivative shaper is selected for the crane. Then, a model predictive swing suppression controller is designed for the crane based on the selected shaper. Constraints on the control input and its slew rate are respected. Besides, the constraint on the swing angle of the payload is also respected as an output constraint. The constrained solution is given in the form of standard quadratic programming. The designed control scheme combines open-loop and closed-loop control techniques, achieving accurate positioning of the trolley and good swing suppression of the payload. A series of simulation demonstrates the effectiveness and advantages of the proposed scheme.

NGHIÊN CỨU DAO ĐỘNG CỦA DẦM CẦU TRỤC KHI CÁC THAM SỐ MÔ HÌNH LÀ ĐẠI LƯỢNG NGẪU NHIÊN

According to the stochastic design method, the state functions of the design conditions are often built with the appearance of the input random variables with the hypothetical distribution functions and the random responses obtained from the solution of the computational model. This article investigates dynamic behavior of an overhead crane within the system parameters as random variables. First, the physical modeling and differential equation describing the motion of the crane system are derived using the Lagrange equation. Then, the numerical Newmark-β integral method is applied for characterizing dynamic responses of the crane system. Finally, the dynamic responses of the bridge beam are investigated when assuming the model parameters follow the normal distribution. The obtained results show that the distribution characteristics of the vibration response parameters of the bridge girder depend on the standard deviation of the input parameters and the position of the trolley during the investigation time. Specifically, a standard deviation value of 0.15 can cause an uncertainty ~75 % of displacement at the cross-section in the middle of the girder.

The novel design of the command smoother for sway suppression of industrial overhead crane considering acceleration and deceleration limits

The novel design of the command smoother for sway suppression of industrial overhead crane considering acceleration and deceleration limits

Virtual constraint generators for motion control of robots with degree of underactuation one

Virtual holonomic constraints (vhcs) are relations among the configuration variables of a mechanical control system that can be rendered invariant via feedback. A regular vhc is a vhc with the property that the accelerations imparted by the control forces are everywhere transverse to the constraint surface. This paper proposes a methodology for the design of regular vhcs for mechanical systems with degree of underactuation one based on the notion of a virtual constraint generator, a control system on the configuration manifold of the mechanical system whose orbits are all the regular vhcs for the mechanical system. Designing a regular vhc corresponds to designing controllers for the virtual constraint generator. We show how to design regular vhcs inducing two kinds of motions for the constrained dynamics: traversal of the vhc in one direction or oscillation back and forth along the vhc. We propose an optimal control problem for the virtual constraint generator whose solutions are regular vhcs inducing the kind of motions just described and, at the same time, meeting geometric requirements such as obstacle avoidance. We demonstrate the utility of our technique by designing a constraint for an overhead crane making the trolley move from left to right with bounded speed while ensuring that the cable angle remains within fixed limits, and a constraint for a cart–acrobot making the cart oscillate back and forth underneath an obstacle placed overhead while ensuring that the acrobot avoids the obstacle and remains as close as possible to being in the upright position.

An Online Adaptive Policy Iteration-Based Reinforcement Learning for a Class of a Nonlinear 3D Overhead Crane

We consider an online policy iteration-based reinforcement learning for a class of a nonlinear three-dimensional overhead crane with bounded uncertainties. Under the assumption that the rope length is fixed with small swing angles, a linearized model is derived. The system has four states; two actuated states: position x and y, and two un-actuated states, which are the rope angles θx and θy. The adaptive reinforcement learning controller is designed to handle the effects of measurement noises and outliers. We propose a model-free; hence it does not require precise knowledge of the system dynamics. When the state information is not available, a Kalman filter estimator is equipped with a dynamical saturation function to attenuate the effects of measurement noises and to remove outliers. A simulation study is established to illustrate the influence and robustness of the developed controller, and it can enhance the tracking trajectory under different scenarios to test the scheme.

Positioning and Swing Elimination Control of the Overhead Crane System with Double-Pendulum Dynamics

Positioning and Swing Elimination Control of the Overhead Crane System with Double-Pendulum Dynamics

Bridge Crane Monitoring using a 3D LiDAR and Deep Learning

The use of overhead cranes in warehouses and factories has advantages for handling and transporting bulky and/or heavy loads. But it also involves risks such as collisions with other fixed or mobile elements in the working environment. Different types of sensors have been used for monitoring its operation, mainly artificial vision. In this paper, it is employed a three-dimensional (3D) LiDAR to capture the workspace of a bridge crane. The point clouds generated by this laser sensor are delivered to a convolutional neural network to detect the position of the bridge and its carriage, which allows to locate the hook and the suspended load afterwards. Additionally, the laser scans can also be used to warn the operator of possible collisions with fixed elements of the warehouse. The tests carried out show that the proposed system can be successfully used for monitoring overhead cranes.

TwinXR: Method for using digital twin descriptions in industrial eXtended reality applications

Digital twins (DTs) and eXtended Reality (XR) are two core technological enablers for engineering in the Metaverse that can accelerate the human-centric Industry 5.0 transformation. The digital twin technology provides a digital representation of a physical asset with data linkages for inspection, monitoring, and prediction of complex processes or systems, while eXtended reality offers real-and-virtual combined environments for human users to interact with machines. However, the synergies between digital twins and eXtended reality remain understudied. This work addresses this research gap by introducing a novel method “TwinXR” that leverages ontology-based descriptions of Digital twins, i.e., digital twin documents, in industrial eXtended reality applications. To ease the use of the TwinXR method, we publish a Unity package that allows data flow and conversion between eXtended reality applications and digital twin documents on the server. Finally, the work applies the TwinXR method in two industrial eXtended reality applications involving overhead cranes and a robot arm to demonstrate the use and indicate the validity of the method. We conclude that the TwinXR method is a promising way to advance the synergies between digital twins and eXtended reality: For eXtended reality, TwinXR enables efficient and scalable eXtended reality development; For digital twins, TwinXR unlocks and demonstrates the potential of digital twins for data interchange and system interoperation. Future work includes introducing more detailed principles of Semantic Web and Knowledge Graph, as well as developing factory-level TwinXR-compatible applications.

Scheduling Algorithm Using Path Relinking for Production Process with Crane Interference

In manufacturing industries, customers demand a wide variety of products, with high quality and fast delivery. Production scheduling systems have become critical for efficient operation. However, scheduling problems in manufacturing are generally large and complex with many constraints. It is difficult to create an optimal production schedule that satisfies all constraints within a reasonable timeframe. This study targets a factory with multiple working machines and two overhead cranes. Our research aims to obtain a solution algorithm to avoid interference of overhead cranes and machine competition and a production plan that minimizes the total makespan for each job. As the problem must be solved within a reasonable timeframe, we have developed the solution algorithm using metaheuristics and scheduling simulation. In general, metaheuristic algorithms must strike a balance between an intensive search for good solutions and a search for diverse solutions. Accordingly, we propose a new algorithm using path relinking in a scatter search. This method was demonstrated to be effective in obtaining good solutions with little variation in numerical experiments. In this paper, we describe previous research, our target process, and new solution algorithm and discuss algorithm design methods based on computer experiments.

Flatness-Based Backstepping Antisway Control of Underactuated Crane Systems under Wind Disturbance

A control method that combines trajectory planning and backstepping is proposed for the antisway problem of underactuated overhead cranes under wind disturbance. First, a set of flat outputs is proposed so that the crane system dynamics can be represented by each order of flat outputs. Sufficient relevant constraints are given to ensure that the trolley can arrive at the desired position in a limited time under variable rope lengths, and that the swing angle can be suppressed when the payload is lifted or lowered during operation. The planned trajectory is obtained by solving for the optimal parameters of the flat output. Next, to reduce the deviation caused by wind disturbance on the actual control of the trajectory, a tracking controller is designed. Because the system output space and flat output space are differentiable homeomorphisms, the backstepping controller constructed based on the flat output can indirectly control the system output, which makes the backstepping method applicable to underactuated cranes. The simulation results show that the proposed method is effective and has strong robustness.

Position-Commanding Anti-Sway Controller for 2-D Overhead Cranes Under Velocity and Acceleration Constraints

This paper proposes an anti-sway controller for two-dimensional overhead cranes. The controller is of the position-commanding type, i.e., it sends position commands to the position-controlled trolley, and it uses the sensor information of the payload sway angle. The position commands are determined so that the trolley tracks the desired position signal sent from an upper-level controller and also so that the payload sway is damped. The sway damping is realized by a leaky integral controller, which employs a high-pass filtered time integral of the sway angle. In addition, arbitrary limits can be imposed on the first and second derivatives of the position command, and thus it is applicable to cases where the desired position signal from the upper-level controller is nonsmooth or discontinuous. Due to these features, the controller is expected to be useful in both human-operated and autonomous systems. The controller was validated with a laboratory setup. This paper also presents an algorithm that can be attached to the proposed controller to prevent the overshoot, which can take place when the desired position signal is discontinuous.

Vibration control of double pendulum type crane system with uncertainty in parameters by elimination of the natural frequency component

Overhead cranes are widely used to transport heavy loads, and their efficient operation requires fast and accurate positioning. However, residual vibration which prevents positioning accuracy generally tends to be induced by fast transportation. In previous paper, we proposed a control method which is based on the characteristic that the residual vibration is completely suppressed in a linear undamped system when excited by an external force which does not contain the natural frequency component of the system. To apply this characteristic to nonlinear damped systems, we defined the apparent external force which includes the influence of system nonlinearity and damping. It was confirmed that the residual vibration of a double pendulum type system model of crane can be suppressed by eliminating two natural frequency components from each the apparent external forces. In this paper, in addition, to improve the robustness for a double pendulum type system against the estimation error, new conditions are added to reduce the component around the natural frequencies from each of the two apparent external forces. The effectiveness of these conditions for robustness is verified through numerical simulations. Furthermore, changes in the robustness are examined when the position of the mass point near the support point of the double pendulum is changed. The results showed that the robustness can be improved in many cases except when the control time is short and the mass point is close to the support point.