Container Crane Research Articles

Design of Digital Twin System for Harbor Cranes Based on Unity 3D

Port container crane (shore bridge) is an important equipment for container loading and unloading in the port, and its working mechanism includes four parts: lifting mechanism, operating mechanism, operating system and equipment structure. In this paper, digital twin technology is integrated to realize the digital mapping of quay bridge operation, which is the basis for realizing predictive maintenance. As a link between the physical space and the digital space, the digital twin is based on a new generation of information technology, which can complete the mapping of the real space in the digital space, so as to reflect the whole life cycle process of the corresponding physical equipment, and can derive related other functions on this basis. Firstly, the bridge was constructed using 3D modeling software solid works, and the mapping and model format conversion were carried out using 3ds Max. Finally, the 3D model was imported into Unity and the port virtual environment was built. Combined with C#, the driving engine of the lifting mechanism and operating mechanism of the quayside bridge is developed, and the virtual and real synchronous operation of the quayside bridge is finally realized.

Chances and Challenges: Transformation from a Laser-Based to a Camera-Based Container Crane Automation System

In recent years, a steady increase in maritime business and annual container throughput has been recorded. To meet this growing demand, terminal operators worldwide are turning to automated container handling. For the automated operation of a crane, a reliable capture of the environment is required. In current state-of-the-art applications this is mostly achieved with light detection and ranging (LiDAR) sensors. These sensors enable precise three-dimensional sampling of the surroundings, even at great distances. However, the use of LiDAR sensors has a number of disadvantages, such as high acquisition costs and limited mounting positions. This raises the question of whether the LiDAR systems of automated container terminals (ACT) can be replaced with cameras. However, this transformation is not easy to accomplish and is explored in more depth in this paper. The field of camera-based container automation presented in this publication is largely unexplored. To the best of our knowledge, there is currently no automated container terminal in real-world operation that exclusively uses cameras. This publication aims to create a basis for further scientific research towards the goal of a fully camera-based container automation. Therefore, the authors present a narrative review providing a broad overview of the mentioned transformation, identifying research gaps, and suggesting areas for future research. In order to achieve this, this publication examines the fundamentals of an automated container terminal, the existing automation solutions and sensor technologies, as well as the opportunities and challenges of a transformation from LiDAR to camera.

ANALYSIS OF CONTAINER CRANE ON STEVEDORING AT NILAM MULTIPURPOSE TERMINAL

Purpose: This study is titled "Analysis of Container Cranes on Stevedoring in Nilam Multipurpose Terminals The Use of Container Crane Against Container Stevedoring in Nilam Multipurpose Terminals". This study aims to determine the effect of using a Container Crane on the productivity of container stevedoring activities at Nilam multipurpose terminals.
 Design/methodology/approach: This study uses a descriptive method with a qualitative approach accompanied by other instruments such as secondary data, interviews and documentation which aims to determine the influence of container crane loading and unloading productivity and also supporting factors that can maximize the performance of the container crane at the Nilam Multipurpose Terminal. The data used as analytical material to support the research is performance data from loading and unloading activities at the Nunukan Island KM in 2016 to 2017 in the first semester
 Findings: The results showed that the role of container cranes is the most important factor in the implementation of container loading and unloading activities at Nilam multiplepurpose terminals.
 Keywords: Container Crane, Stevedoring, Container

Pengaruh Performa Quay Container Crane dan Penerapan System Single Cycle dan Dual Cycle Terhadap Bongkar Muat Peti Kemas di KSO Peti Kemas Koja Jakarta

Since 2012 Koja Jakarta Container Terminal has a target of unloading and loading 1 million containers. To get the desired target, KSO Koja Container Terminal immediately took quick steps by upgrading and adding several tools to support performance so that it could be more optimal in carrying out loading and unloading activities such as upgrading several CCs from Post Panamax grade to Super Post Panamax. Along with the many containers that are unloaded or loaded at TPK KOJA, and the market that competes between container terminals with each other. The management of Koja must increase the target size of unloading and loading containers by quay container crane (QCC) or what we often call Box Crane per Hours (BCH), but on the other hand with the demands of TPK KOJA management that unloading and loading 1 million containers, many tools in the field and at the dock are forced to work hours with maintenance that has not been scheduled properly resulting in congestion of loading and unloading equipment. The type of research used in this study is qualitative descriptive analysis, qualitative descriptive research is aimed at describing and describing existing phenomena, both natural and human engineering, which pay more attention to the characteristics, quality, relationships between activities. In addition, descriptive research does not provide treatment, manipulation or alteration of the variables studied, but describes a condition as it is. So the results of the Quay container crane performance research at TPK Koja from the author's observation, in the process of container loading and unloading activities at TPK Koja still found inhibiting factors. The effect of the Dual Cycle Operation system in loading and unloading at TPK KOJA cannot be determined the box crane unit per hour produced, because in this case the management of TPK KOJA is still in the trial stage of the system.

QUAY CONTAINER CRANE PRODUCTIVITY EFFECTIVENESS ANALYSIS (CASE STUDY JAKARTA INTERNATIONAL CONTAINER TERMINAL)

The purpose of this study is to determine the effectiveness and productivity of Quay Container Crane (QCC) work through the value of OEE (availability, performance, quality) and identify losses affecting the OEE value of QCC. The method used is a explorative and descriptive analysis, which exposes availability, performance and quality of Quay Container Crane based on actual data and information by collecting, compiling, classifying and analysing data and information about the effectiveness and productivity of Quay Container Crane. The results of the OEE are analysed using the six big losses method to find the loss factor, root cause analysis using the Fishbone diagram and make improvement recommendations using the 5 why analysis method. Based on the research results, the OEE value of Quay Container Crane affected by the loss factor which are reduce speed losses, breakdown losses and idling and stoppage losses. The root of the problem comes from various causes, among others, many breakdown on spreaders, the maintenance schedule is still not correct, the operator's competence and knowledge are still lacking, and the technical problems in the Quay Container Cranes.

The Effect of Training and Work Motivation on Operator Performance During the COVID-19 Pandemic

This research was conducted on a quay container crane operator at KSO TPK Koja. The quantitative research method was collecting data on 28 questionnaires and using SPSS version 21 applications to analyze data. The study used the validity, reliability, normality and hypothesis test. This study aimed to identify the influence of training and work motivation on operator performance during the COVID-19 pandemic at KSO TPK Koja. The result of this study showed that training and work motivation have a positive influence on operator performance, but training had no significant effect on operator performance. In addition, work motivation had a significant influence on operator performance.
 Keywords: Training, Work Motivation, Operator Performance, COVID-19

Anti-sway control of variable rope length container crane based on phase plane trajectory planning

An overhead crane system is a complex time-varying system if it includes simultaneous hoisting and moving operations. To address the problem that time-varying systems usually have no exact analytical solution, an anti-swing method based on linear approximation of the phase plane trajectory is proposed. Specifically, the phase plane trajectory of the swing angle is first analyzed and it is found that the double-step acceleration method with unequal acceleration amplitude and acceleration time has a combination of limit loops in the phase plane trajectory of the swing angle when the rope length varies, so the average rope length of each section is used to approximate the natural oscillation frequency. Next, the input shaping technique is used to shape the input signal into the desired output signal so that the load swing angle can follow the planned trajectory. The desired acceleration amplitude and switching time are then derived based on the geometric relationship between the swing angle in the phase plane and the specific physical constraints. Finally, the feasibility of the proposed method is verified by numerical simulations.

Robust fault diagnosis of quayside container crane gearbox based on 2D image representation in frequency domain and CNN

To accurately diagnose the quayside container crane (QCC) gearbox faults, this article proposes a method that combines the frequency-domain Markov transformation field (FDMTF) and multi-branch residual convolutional neural network (MBRCNN). Firstly, the gearbox vibration signal is converted into the frequency domain to reveal the components and amplitude of signals stably and concisely. Then, the one-dimensional frequency signal is encoded into the two-dimensional image by the Markov transformation field to capture the dynamic characteristics of signals. Thirdly, the MBRCNN network is constructed, which can extract multi-scale features and alleviate the problems caused by the deep network structure. Finally, the FDMTF image is fed into the constructed MBRCNN model for pattern recognition. The effectiveness of the proposed FDMTF–MBRCNN method is verified by two case studies. In Case 1, the diagnosis results of a benchmark dataset achieve 100% accuracy, better than seven state-of-the-art methods published in recent 3 years. In Case 2, the diagnosis results of the dataset collected from a 1:4 scaled test rig achieve 98.85% accuracy, better than eleven encoding methods and four convolutional neural network methods. It also can obtain a recognition accuracy of more than 94% under the conditions of small sample, different network hyper-parameters, or variable loads, which verifies its robustness. These case studies show that the FDMTF–MBRCNN method is expected to be applied to the actual fault diagnosis of QCC gearboxes.

Smart ports: towards a high performance, increased productivity, and a better environment

<span lang="EN-US">Ports are currently competing fiercely for capital and global investments in order to improve revenues, mostly by improving performance and lowering labor costs. Smart ports are a fantastic approach to realize these elements since they integrate information and communication technologies within smart applications, ultimately contributing to port management improvement. This leads to greater performance and lower operational expenses. As a result, several ports in Europe, Asia, Australia, and North America have gone smart. However, there are a lot of critical factors to consider when automating port operations, such as greenhouse gas emissions, which have reached alarming proportions. The purpose of this study is to define the most essential tasks conducted by smart ports, such as the smart ship industry, smart gantry and quayside container cranes, transport automation, smart containers, and energy efficiency. Furthermore, it gives a model of the smart port concept and highlights the critical current technologies on which the ports are based. Each technology’s most significant contributions to its development are noted. This technology is compared to more traditional technologies. It is hoped that this effort would pique the curiosity of fresh researchers in this sector.</span>

Gearbox fault diagnosis based on frequency-domain Gramian angular difference field and deep convolutional neural network

Gearbox fault diagnosis is of great significance to avoid accidents and reduce operation and maintenance costs for machinery such as the quayside container crane. In recent years, mechanical fault diagnosis methods based on deep learning have developed rapidly. How to perform diagnosis simply based on deep learning in the case of limited labeled samples is still a challenging problem. To address this issue, this paper proposes a new fault diagnosis method combining the frequency-domain Gramian angular difference field (FDGADF) and deep convolutional neural network (DCNN), namely, FDGADF-DCNN. To explore the availability of the FDGADF-DCNN method, two experiment datasets are studied. When the proportion of labeled samples is 70%, the recognition accuracy of both datasets exceeds 98%. When only 20% of the labeled samples are available (the average number of training samples in each category is only dozens), FDGADF-DCNN can achieve a recognition accuracy of no less than 95% in two datasets, in which a benchmark dataset is 100% and the dataset collected from a scaled-down test bench is 95%. Compared with other 11 methods, the FDGADF-DCNN method achieves the highest recognition accuracy. These results indicate that the FDGADF-DCNN method is expected to be used for gearbox fault diagnosis under limited labeled samples.

Analisa Kekuatan Tali Baja Sling Crane Berkapasitas 40,6 Ton Di PT. Pelindo IV (Persero) Kendari

At the port usually the tools used as moving goods are container cranes, container cranes have the main component of steel rope slings which function as lifting cables on the hoist, usually chosen according to the needs of a construction for that it is necessary to analyze the strength of the steel rope slings currently used and comparing the steel rope with other types of steel rope in order to obtain a more comprehensive understanding of alternative steel rope selection that is appropriate for use in container/container lifting mechanisms. Research Objectives To analyze and determine the strength of a sling crane steel rope with a capacity of 40.6 tons and to determine the electrical power used. The research method is to make observations to determine the length of the steel rope using a roll meter and the diameter of the steel rope using a caliper. research, namely the calculation on wire rope obtained 3,896, kg, the cross-sectional area of the steel rope is 615.44 mm², the breaking stress is 6,330 kg/mm², the permissible breaking load of the steel rope is 12,150 kg, the tensile stress on the steel rope is 2,518 kg, the calculation on driving machine The resulting power (N) is 40.21 kW, the moment of static resistance on the motor shaft (M) is 239.927 kg.m.Keywords: Container, crane, steel rope, container

Seismic Fragility Analysis of Container Crane Considering Far-Fault and Near-Fault Ground Motion Characteristics

Seismic Fragility Analysis of Container Crane Considering Far-Fault and Near-Fault Ground Motion Characteristics

Damping coefficient calculation method for shore-side container cranes under the seismic conditions

Shore-side container cranes (SCC) are widely used in ship loading and unloading. However, the SCC is often damaged by the seismic wave shock. In seismic response analysis, the setting of damping coefficients has a large impact on the accuracy of the calculation results. In order to better design the SCC mechanical performance, the improved damping coefficient calculation method is proposed. The results of the simulation and the experiment are compared under the different seismic conditions. The results show that the influence of the damping coefficient calculation method on the SCC seismic response increases with strengthened seismic intensity. When the peak acceleration is small, the simulation results under different damping coefficients are almost the same and are close to the experiment values. When the peak acceleration is large, only the error between the simulation results obtained by the improved method and the experimental values is less than 5%. It is thus concluded that the improved damping coefficient calculation method is accurate and reliable.

Event-triggered global sliding mode controller design for anti-sway control of offshore container cranes

This paper proposes an event-triggered global sliding mode based anti-sway control for offshore container cranes. Its main objective is to guarantee the robust tracking performance of containers transferred by cranes installed on cargo ships, while saving the transmission resources. To this end, a suitable sliding manifold is formulated with the desired motion properties. A global sliding mode control is then synthesized to maintain stability of the system and ensure robustness against disturbances such as sea waves and wind induced movements. Finally, the event-triggered strategy is considered in the implementation phase to generate the sampling instant at which the control signal is updated, thereby minimizing communication resources and execution time. Using the Lyapunov's stability theory, it is proven that the controlled system reaches the manifold and equilibrium point from any initial state. We also prove that the proposed approach is free from the Zeno solution, i.e., a phenomenon when the infinite triggering instants exist in a limited time range. Eliminating the reaching phase of traditional sliding mode control, overcoming the effect of the disturbances during the entire dynamics, optimizing resources at the implementation phase, and removing the Zeno phenomenon are among the main advantages of the proposed control approach.

Dynamic Analysis and Structure Parameter Research on a Hydraulic Anti-Swaying System for Container Cranes

An anti-swaying or swaying-reduction effect for a container crane is key for improving the rapidity and safety of container handling operations. By analyzing the structure of a container crane hydraulic anti-swaying system, a dynamic system model was developed in the time domain, and the changing law of the load swaying angle was studied. In order to study the attenuation effect of the load swaying angle and the different working states of the anti-swaying system, the frequency domain equation of the load swaying angle was developed in the frequency domain. A time domain study on the dynamic model shows that the structure parameter is the key parameter that affects the load anti-swaying effect, and a larger structure parameter produces a better anti-swaying effect. A study regarding the load swaying angle in the frequency domain shows that the container crane hydraulic anti-swaying system works in a critical-damping state when the structure parameter load ratio is equal to twice the system frequency, and in this case, the hydraulic anti-swaying system has good load swaying-reduction effect and a small dependence on changes in the hoisting rope length. The longitudinal and transverse installation distances of the anti-swaying fixed pulleys jointly affect the structure parameter. In engineering applications, the longitudinal and transverse distances can be selected according to size near that of a standard container. To obtain a good swaying-reduction effect, data such as the hoisting load mass, the hoisting rope length, and the hoisting load swaying speed can be obtained in real-time and used to calculate the required pressure adjustments for the relief valve of the hydraulic anti-swaying system.

Development of computer vision informed container crane operator alarm methods

To reduce the extra work, the operation cost, and the risk of cargo delay induced by the unloading of wrong containers, this study first develops a container color detection model to predict the color of the container being unloaded. The prediction results are then used to develop two crane operator alarm methods. Method 1 alerts the crane operator if the detected color of a container is not in compliance with the correct container color. Method 2 constructs a decision problem to decide whether to alert the operator. The results of numerical experiments show that methods 1 and 2 are better than the benchmark. Specifically, method 1 can save the expected annual total cost by about 82% while method 2 can save the expected annual total cost by about 85%. Extensive sensitivity analysis is also conducted to verify the methods performance and robustness.

A Time-Varying PD Sliding Mode Control Method for the Container Crane Based on a Radial-Spring Damper

For the multi-rope structure of the container crane system and its large mass payload anti-swing positioning problem, an equivalent double-swing model based on radial spring-dampers is established and a time-varying PD sliding mode controller (TVPD-SMC) with improved transient performance is proposed. In particular, the dynamics of the container crane system are first analyzed using the Lagrange method, and an equivalent double pendulum dynamics model of the crane is established. Compared with the traditional double pendulum model, this model ensures the accuracy of modeling without measuring the second pendulum angle. On this basis, an enhanced coupled time-varying sliding mode control method is designed to eliminate the sliding mode control method’s reaching phase and improves the robustness of the controller. Finally, the convergence and stability of the closed-loop system are proved using the Lyapunov technique and the Lasalle invariance theorem, and the simulation results demonstrate the effectiveness of the method.

The Interference Effects of Wind Load and Wind-Induced Dynamic Response of Quayside Container Cranes

Strong wind has caused damage to group-arranged quayside container cranes in terminals and ports in recent years. Interference may amplify the wind loads in some cases. However, the interference effect among cranes has rarely been studied. In this study, high-frequency force balance tests were conducted to obtain the wind load of isolated and group-arranged container cranes. The results of the computational fluid dynamics simulation were validated by wind tunnel tests and provided the mean wind loads of all 15 types of member cranes. According to the results from wind tunnel tests, the fluctuating wind loads of each member were generated using the weighted amplitude wave superposition method. Based on dynamic finite element methods, the wind-induced responses were obtained considering the interference effect. It was found that the interference effect is the combined effects of both the shielding effect and the amplification of turbulence. Although in some cases the fluctuating and peak wind loads can increase by up to 16% and 6%, respectively, those in the most unfavorable cases are reduced by the interference effect. The interference factor for extreme nodal deformation is 0.56 and 0.69. The interference effect in container cranes mainly appears as a shielding effect, reducing the wind loads and response of the structures in unfavorable cases.

Motion Generation for Crane Simulators Using Streamlined Motion Blending Technology

For development of a simulator with a motion platform to generate an appropriate motion to reproduce the motion sense for the users, one of the most significant but disregarded complicated tasks is to build up a dynamic virtual motion model to reflect the motion of the simulated object in the corresponding physical world. Recently, a motion generation method based on motion blending technology was developed to alleviate the complication involved. It decomposes the simulated motion into a great number of parameterized motion blocks which are depicted by real motion data acquired from field tests and stored in a database. This paper proposes a streamlined motion blending technology suitable for a container crane simulator to further improve the current motion generation method based on the motion blending technology. Motion components, rather than motion blocks specially marked and stored in a database, are taken as the basic motion unit easily acquired through united analysis of crane dynamics and motion perception characteristics. They are then blended on demand to produce a one-stop model to directly act as the driving command of the motion platform without the need for a subsequent dedicated wash-out procedure. The calculation workload is greatly reduced and finally allows for achievement of higher fidelity of motion perceptions. Experiments are conducted to verify the effectiveness of the proposed streamlined motion blending technology for motion perception generation. Better training effect is found to be achieved due to more realistic simulation effects. The comprehensive training effectiveness index is enhanced from 54% to 82% once a motion simulation system developed using the proposed approach is introduced into the crane simulator.

Adaptive Hierarchical Sliding Mode Control Design for 3D Ship-Mounted Container Crane with Saturating Actuators

Adaptive Hierarchical Sliding Mode Control Design for 3D Ship-Mounted Container Crane with Saturating Actuators