Multiple Cranes Research Articles

Model and Heuristic Solutions for the Multiple Double-Load Crane Scheduling Problem in Slab Yards

This article studies a multiple double-load crane scheduling problem in steel slab yards. Consideration of multiple cranes and their double-load capability makes the scheduling problem more complex. This problem has not been studied previously. We first formulate the problem as a mixed-integer linear programming (MILP) model. A two-phase model-based heuristic is then proposed. To solve large problems, a pointer-based discrete differential evolution (PDDE) algorithm was developed with a dynamic programming (DP) algorithm embedded to solve the one-crane subproblem for a fixed sequence of tasks. Instances of real problems are collected from a steel company to test the performance of the solution methods. The experiment results show that the model can solve small problems optimally, and the solution greatly improves the schedule currently used in practice. The two-phase heuristic generates near-optimal solutions, but it can still only solve comparatively modest problems within reasonable (4 h) computational timeframes. The PDDE algorithm can solve large practical problems relatively quickly and provides better results than the two-phase heuristic solution, demonstrating its effectiveness and efficiency and therefore its suitability for practical use. Note to Practitioners-Bridge cranes are commonly used to move heavy items in manufacturing and logistics systems. Generally, more than one crane runs on a common track. The latest versions of such cranes, such as those used in slab yards in the steel industry, can hold two items simultaneously. Operations scheduling of multiple double-load cranes involves the assignment of tasks to the cranes, the combination of tasks to double-load operations, and sequencing of the tasks, considering the noncrossing constraint between cranes. Effective solution of this complex problem can help to fully utilize the crane capability, increase productivity, and reduce energy consumption. This article models this problem and develops a heuristic solution that combines differential evolution (DE) and DP. Experiment results show that the algorithm is effective and efficient for practical use in slab yards. It may also be applicable to other systems using similar cranes.

Scheduling multiple yard cranes in two adjacent container blocks with position-dependent processing times

This paper studies the management of three yard cranes in two adjacent container blocks in line, where cranes can move from one block to the other. Comparing with existing literature, the new multi-yard-crane scheduling problem incorporates different constraints together: (i) three yard cranes are deployed simultaneously in two adjacent blocks, (ii) non-crossing and inter-crane interference constraints of yard cranes are considered, (iii) the processing time of each container depends on its real-time location, i.e., position-dependent processing times. For the problem, a 0–1 mixed integer programming (MIP) model is constructed to minimize the total flow time to reduce the total container storage time in container yards, which helps to save container yard resources and increase production efficiency. The proposed model can be solved optimally by CPLEX for small-size instances. As the concerned problem is NP-hard, a fast heuristic and an improved genetic algorithm are devised to produce near-optimal solutions for large-size instances. Numerical experiments validate the developed MIP model and demonstrate the efficiency of the proposed algorithms.

An Improved Storage-Space Selection Model and Algorithm for Outbound Shipping Containers: Considering the Synchronous Operation of Multiple Gantry Cranes in Port Terminals Worldwide

ABSTRACT Zheng, S.; Sha, J., Wang, A., 2019. An improved storage-space selection model and algorithm for outbound shipping containers: Considering the synchronous operation of multiple gantry crane...

Discrete-Event Systems Modeling and the Model Predictive Allocation Algorithm for Integrated Berth and Quay Crane Allocation

In this paper, we study the problem of integrated berth and quay crane allocation (I-BCAP) in general seaport container terminals and propose the model predictive allocation (MPA) algorithm and preconditioning methods for solving the I-BCAP. First, we propose a dynamical modeling framework based on discrete-event systems (DESs), which describes the operation of a berthing process with multiple discrete berthing positions and multiple quay cranes. Second, based on the discrete-event model, we propose the MPA algorithm for solving the I-BCAP using the model predictive control (MPC) principle with a rolling event horizon. The validation and performance evaluation of the proposed modeling framework and allocation method are done using: 1) extensive Monte Carlo simulations with realistically generated datasets; 2) real dataset from a container terminal in Tanjung Priuk port, located in Jakarta, Indonesia; and 3) real life field experiment at the aforementioned container terminal. The numerical simulation results show that our proposed MPA algorithm can improve the efficiency of the process where the total handling and waiting cost is reduced by approximately 6%–9% in comparison with the commonly adapted method of first-come first-served (FCFS) (for the berthing process) combined with the density-based quay cranes allocation (DBQA) strategy. Moreover, the proposed method outperforms the state-of-the-art hybrid particle swarm optimization (HPSO)-based and genetic algorithm (GA)-based method proposed in the recent literature. The real life field experiment shows an improvement of about 6% in comparison with the existing allocation method used in the terminal.

A generator for test instances of scheduling problems concerning cranes in transshipment terminals

We present a test data generator that can be used for simulating processes of cranes handling containers. The concepts originate from container storage areas at seaports, but the generator can also be used for other applications, particularly for train terminals. A key aspect is that one or multiple cranes handle containers, that is, they store containers, receiving the containers in a designated handover area; retrieve containers, handing the containers over in the handover area; or reshuffle containers. We present a generic model and outline what is captured by the test data itself and what is left to be estimated by the user. Furthermore, we detail how data are generated to capture the considerable variety of container characteristics, which can be found in major terminals. Finally, we present examples to illustrate the variety of research projects supported by our test data generator.

Design and Fabrication of Lifting Beam for Air Pre Heater Centre Section Parts

The project deals with the reduction of using multiple cranes during the lifting of the Centre section parts and introducing a new system called lifting beam. The lifting beam is designed to carry a weight of 18- 20tons with the self weight of 2-2.5 tons ,reducing the involvement of more number of employees and eliminating the unwanted processes like gas cutting and welding during multiple crane usage, which results in making the Air pre heater (APH) to preheat the fresh Atmospheric air which takes the heat from outgoing Exhaust gas. APH is the device to improve the efficiency that is used generally in the thermal power plants, the main aim of this project also lies in making the lifting beam the versatile one which must be used for both the types of the centre section parts i.e., both the type of pre heaters that are being manufactured in the company of different power capacity of respective length 16 and 18 meters.

Design Considerations for Automated Crane Assignment

This paper describes a method of multiple cranes assignment to operators who call cranes in a factory. Due to a crane moving on a rail, there is a restriction on the movement. Therefore, the crane cannot be delivered without proper assignment. To solve the cranes assignment problem, we propose two methods. The first is the optimal solution search method which finds the minimum travel distance combination from the number of cases that are derived by calculating the distance between all the cranes and all the operators. The second is the dynamic mapping method which finds the number of operators between each crane. Simulation results show that the dynamic mapping method sometimes performs the same assignment results as the optimal solution search method, but on average, the result of dynamic mapping method is farther than the optimal solution as the number of cranes increases. When partial regions are created by using the dynamic mapping method and an optimal solution search method is applied to each region, optimal solutions can be acquired while reducing the number of calculations.

Probability Analysis of Crane Load and Load Combination Actions

This study presents probability models of crane load and load combination actions for reliability analysis of the industry buildings. Crane load values are simplified here only varying in time, and load combination actions only vary in space. With the feasible survey program and K-S test, the Gumbel distribution is chosen as the probability distribution of the arbitrary point-in-time crane load values with the statistical investigation data. With the simple stationary binomial random process model hypothesis and the block maxima method, it determined that the maximum value of crane load during the design reference period also follows the Gumbel distribution, with the peaks-over-threshold method evaluation. For multiple crane load combination actions, the modified Turkstra rule is improved to determine the probability distribution of the actions as the Gumbel distribution by considering the occurrence probability, numbers, location, and values of each crane load acting on the influence line, evaluated by the Monte Carlo simulations. Design standard values for crane loads and load combination actions, as specified in building codes, are evaluated based on these distributions in probability significance. The calculation results illustrate that the design standard values for crane loads are relatively safe and conservative.

Optimal Job Scheduling of Multiple Rail Cranes in Rail Stations

Optimal Job Scheduling of Multiple Rail Cranes in Rail Stations

Characteristics of Equipment Planning for Multi-Crane Building Construction Sites

This paper purports to provide answers to the following questions with regard to multi-crane building construction sites: (1) Do such construction sites differ from smaller sites only in magnitude, or are there unique characteristics that stem from the size of the site and the multitude of cranes? (2) Is equipment planning for such projects similar to that of projects serviced by a small number of cranes? (3) How is equipment planning affected by the site’s surroundings? (4) Does the visibility of multiple cranes in the near and far surroundings of the project affect the approach to equipment planning? Answers to these questions were sought after through the investigation of several measures, based on case studies of mega building projects in Europe, all located in busy urban surroundings. On-site interviews focused on multiple research variables, of which four are used here: project planning stages, planning parties, plan formats, and the cranes on site. The study found that multi-crane sites are characterized by unique features; equipment planning for such sites differs significantly from that conducted for regular sites; the site-surroundings interface plays an important role in equipment and logistics planning for such sites; and the awareness of reputation plays a role in crane selection. The study’s main contribution is in reducing the knowledge gap that exists with regard to the unique determinants of equipment planning for multi-crane projects and to its importance to the success of such projects.

Optimally scheduling interfering and non‐interfering cranes

AbstractThis article treats the problem of scheduling multiple cranes processing jobs along a line, where cranes are divided into different groups and only cranes in the same group can interfere with each other. Such crane scheduling problems occur, for example, at indented berths or in container yards where double rail‐mounted gantry cranes stack containers such that cranes of the same size can interfere with each other but small cranes can pass underneath larger ones. We propose a novel algorithm based on Benders decomposition to solve this problem to optimality. In a computational study, it is shown that this algorithm solves small and medium‐sized instances and even many large instances within a few seconds or minutes. Moreover, it improves several best known solutions from the literature with regard to the simpler problem version with only one crane group. We also look into whether investment in more complicated crane configurations with multiple crane groups is actually worthwhile.

Multiple quay cranes scheduling for double cycling in container terminals.

Double cycling is an efficient tool to increase the efficiency of quay crane (QC) in container terminals. In this paper, an optimization model for double cycling is developed to optimize the operation sequence of multiple QCs. The objective is to minimize the makespan of the ship handling operation considering the ship balance constraint. To solve the model, an algorithm based on Lagrangian relaxation is designed. Finally, we compare the efficiency of the Lagrangian relaxation based heuristic with the branch-and-bound method and a genetic algorithm using instances of different sizes. The results of numerical experiments indicate that the proposed model can effectively reduce the unloading and loading times of QCs. The effects of the ship balance constraint are more notable when the number of QCs is high.

Multiple crane scheduling in a batch annealing process with no-delay constraints for machine unloading

• We model the problem as a mixed integer linear programming (MILP) model. • Some feasible properties are proposed. • A heuristic algorithm is proposed and further its worst case bound is analyzed. • The lower bound to the problem is also developed. • The proposed heuristic algorithm is capable of generating good quality solutions. In this work, we focus on the scheduling of multi-crane operations in an iron and steel enterprise for a two-stage batch annealing process. The first stage is the heating process, and the second stage is the cooling process. To start the heating (cooling) stage, a special machine called a furnace (cooler) must be loaded. The real constraints of no-delay machine unloading are defined as follows: once the heating (cooling) is completed, the furnace (cooler) must be unloaded by crane immediately. The goal is to schedule limited machines (furnaces and coolers) operated by multiple cranes to minimize the completion time of the last annealed coil ( makespan ). We formulate a mixed-integer linear programming model to address this problem. Certain feasible properties are identified to avoid crane conflicts and ensure that the machine unloading no-delay constraints are met. Based on these necessary conditions, we then present a heuristic algorithm with running time in connection with the number of cranes, coils and machines. A lower bound to the problem is also developed. Through theoretical analysis, we show the worst-case bound of our heuristic algorithm. The average performances of the solution approaches are computationally evaluated. The computational results show that the proposed heuristic algorithm is capable of generating good quality solutions.

Event-based scenario manager for multibody dynamics simulation of heavy load lifting operations in shipyards

This paper suggests an event-based scenario manager capable of creating and editing a scenario for shipbuilding process simulation based on multibody dynamics. To configure various situation in shipyards and easily connect with multibody dynamics, the proposed method has two main concepts: an Actor and an Action List. The Actor represents the anatomic unit of action in the multibody dynamics and can be connected to a specific component of the dynamics kernel such as the body and joint. The user can make a scenario up by combining the actors. The Action List contains information for arranging and executing the actors. Since the shipbuilding process is a kind of event-based sequence, all simulation models were configured using Discrete EVent System Specification (DEVS) formalism. The proposed method was applied to simulations of various operations in shipyards such as lifting and erection of a block and heavy load lifting operation using multiple cranes.

Scheduling Multiple Yard Cranes with Crane Interference and Safety Distance Requirement

Container terminals require robust scheduling algorithms for yard cranes to optimally determine the sequence of storage and retrieval operations in yard blocks for higher container terminal performance. This paper investigates the multiple yard crane scheduling problem within a generic yard block and considers the operational restrictions such as the crane noncrossing constraint and models the crane travel time realistically. Further, the fact that any two adjacent cranes must keep an operational safety distance is also taken into consideration. These physical constraints limit the mobility of yard cranes and greatly render the scheduling difficulty for such pieces of equipment. This paper proposes a clustering-reassigning approach, which fully considers all of the operational constraints in practice. The complexity of the approach is o(n3), where n is the number of container moves to be scheduled, making it suitable for real-time scheduling. Numerical experiments and benchmark with a continuous time-based mixed-integer linear programming model indicate that the clustering-reassigning approach can provide satisfactory near optimal solutions for different sets of test cases in a real-time scheduling context.

Dynamics and trajectory tracking control of cooperative multiple mobile cranes

This paper addresses the dynamics and trajectory tracking control of cooperative multiple mobile cranes. Compared with a single mobile crane, cooperative cable parallel manipulators for multiple mobile cranes (CPMMC) are more complex in configuration, which have the characters of both series and parallel manipulators. Therefore, for the CPMMC, the forward as well as the inverse kinematics and dynamics include the difficulties of both series and parallel manipulators. However, the closed kinematic chain brings about potential benefits, including sufficient accuracy, higher cost performance, better lifting capacity and security. Firstly, the forward and inverse kinematics of the CPMMC with point mass are derived with elimination method, and the complete dynamic model of the CPMMC is established based on Lagrange equation and the complete kinematics. Secondly, considering the repetitive tasks and high security and precision requirement, a robust iterative learning controller is designed for trajectory tracking on the basis of the linearization of the dynamics. Thirdly, taking the engineering practice into consideration, two case studies are simulated with the same expected trajectory but with different weights of the loads. Finally, the designed controller is compared with traditional PD control algorithm via numerical simulation. The results demonstrate the feasibility and superiority of the CPMMC and designed controller, and provide a theoretical basis for the cooperation of multiple mobile cranes.

Inverse Kinematic Control of a Dual Crane System Experiencing Base Motion

For over 30 years, many active and passive antipendulation concepts have been explored for use on cranes in the marine environment. These range from simple tension member restraints to command filtering strategies and advanced feedback control laws, where both measured ship/platform motion and payload swing are required. Single crane control systems that compensate for own ship or target ship motion and payload swing damping are well developed, and have been demonstrated. Cargo transfer control is more complex when multiple ship-mounted cranes are used, representing a closed kinematic chain. However, the potential benefits include larger capacity and better load control. In this brief, an inverse kinematic control strategy is presented that uses two cranes' actuation capability (hoist lengths and boom angles) to keep its load fixed in inertial space regardless of the motion of the ship on which the cranes are mounted. An underdetermined solution is developed. Unique crane commands can then be computed using a minimum norm solution. A dynamic simulation is described for use in algorithm development and initial validation. Final verification was performed using two cranes mounted on a motion controlled platform.

Localization, obstacle avoidance planning and control of a cooperative cable parallel robot for multiple mobile cranes

This paper addresses the cooperative problems in terms of localization, obstacle avoidance planning and automatic leveling control for a cable parallel robot for multiple mobile cranes (CPRMCs). The design model of the CPRMCs is elaborated on. The three-dimensional grid map method is utilized to plot the environment map based on the operation environment model. By combining the relative localization method with the absolute localization method, a cooperative localization scheme of the CPRMCs is developed, and an improved localization algorithm is designed on the basis of multilateration method. Then, according to the grid-based artificial potential field method, a global path planning of the CPRMCs is performed. Considering the possible collision of the single mobile crane, the sensor technology is applied to the cooperative obstacle avoidance. In addition, a four-point collaborative leveling method is adopted for automatic leveling control of the platform of the CPRMCs. Finally, the effectiveness of the CPRMCs system is verified through simulations. Cable parallel robots for multiple mobile cranes are designed.Localization analysis of the robots are reported.Obstacle avoidance planning and automatic leveling control are performed.Illustrative simulation studies highlight the performance of the robots.

The study of intelligent scheduling algorithm oriented to complex constraints and multi-process roller grinding workshop

Roller grinding workshop is a typical multi-unit and multi-task manufacturing scenario, which is aimed to repair the surface damage of the rollers caused by the rolling process, so that the rollers can be reused. Due to the process complexity of roller grinding workshop and the large volume and weight of the roller, hoisting and transportation mode with multiple cranes is required. Consequently, the scheduling of the roller grinding workshop needs to consider both the task sequencing in time and the noninterference of the multi-crane trajectory in space. In this paper, the intelligent scheduling of roller grinding workshop is studied based on the characteristics of complex tasks and space-time coupling constraints. Firstly, the scheduling basis is established based on priority rules and process constraints. In order to solve the scheduling problem under the space-time coupling constraints, the position coordinate system is established, and then the algorithms of crane position tracking and cooperative motion without interference are developed. Further, considering the transportation time of crane and its out of sync time point with the processes, the intelligent decision and scheduling algorithm are developed based on the dynamic priority strategy defined to realize scheduling, including time decision, crane decision, and process decision. With the developed intelligent scheduling algorithm applied, the simulation of the roller grinding workshop is conducted under three combinations of priority strategy and noninterference strategy to verify algorithm performance. Under the guarantee of crane noninterference during the full production, the efficiency is improved by 22.1% compared with the existing processing mode of industry. Additionally, EPTR (effective process time rate) based on dynamic priority strategy and noninterference strategy B is up to 100% to avoid intervals between two processes in the scheduling. The dynamic priority developed in this paper reveals more efficiency than MOR principle, while with the strategy B the CUR (crane utilization rate) can be improved more than 20% under the condition of enough machines which facilitates to obtain shorter makespan than strategy A. The intelligent scheduling algorithm developed guarantees the effectiveness and rationality of scheduling with multi-unit and multi-task under the complex constraints. Finally, in order to realize the automatic and intelligent operation of the roller grinding workshop, the management software of the roller grinding workshop is developed by integrating the intelligent scheduling algorithm, which realizes the intelligent production, monitoring, and management of the roller grinding workshop during the full production cycle.

컨테이너터미널에서 생산성 향상을 위한 이송장비 풀링시스템 적용방안에 관한 연구

컨테이너터미널의 증가로 터미널 물량이 분산되어 기존 물동량 보존과 새로운 물동량 유치 경쟁이 치열해지고 있으며 이에 터미널 물동량 처리 능력과 유치에 다양한 방법을 모색하고 있다. 컨테이너터미널은 물동량처리 능력을 향상시키기 위해서 최신 장비 확충과 최신 터미널 시스템 개발을 통해 터미널의 생산성 향상과 효율성 극대화에 노력을 기울이고 있다. 컨테이너터미널의 생산성 향상에 영향을 줄 수 있는 요인은 다양하게 존재 한다. 그중 야드 이송장비의 경우, 특정 선석크레인(GC, Gantry Crane)에 야드 트랙터(YT, Yard Tractor)가 고정 할당되는 방식에서 다수 선석크레인(GC, Gantry Crane)에 야드 트랙터(YT, Yard Tractor)가 적절하게 분산 할당 방식으로 처리하는 Pooling System으로 전환하게 되면 터미널 생산성과 YT의 가용성을 높일 수 있다. 컨테이너터미널에서 생산성 지표가 되는 KPI는 GC 생산성이고 GC 생산성은 물리적인 GC 작업 속도를 넘어설 수 없기에 Pooling System 적용하여 생산성을 높이는데 의미와 효과는 크다. 본 논문에서는 컨테이너터미널에서 생산성 향상을 위해 이송장비 운영을 더 효율적으로 할 수 있도록 Pooling System 알고리즘을 제시하고 실제로 컨테이너터미널에 적용하여 Non Pooling System과 Pooling System 생산성을 비교하였다. 이송장비 풀링시스템을 도입하여 타 터미널에 비해 생산성을 향상함으로써 터미널 비즈니스에 있어 지속적인 서비스 질과 수익성 향상을 위한 필수불가결한 요소가 될 수가 있다. Due to the increase of container terminals, as the volume of terminals become distributed, the competition of preserving existing volume and inviting new volume are becoming fierce, and various ways for processing terminal volume and inviting volume are being sought. Container terminal efforts to maximize efficiency in order to improve the volume handling capability and productivity by both expansion of the latest equipment and development of the latest terminal system. There are a variety of factors that influence the improvement of productivity at container terminals. Among them, in the case of yard transfer equipment, if it were to convert from the method of a Yard Tractor(YT) being fixed allocated to a certain Gantry Cranes(GC) to a Pooling System that processes in a method that properly distributes and allocates a Yard Tractor(YT) to multiple Gantry Cranes(GC), the terminal productivity and the fusibility of YT may be increased. The KPI which is an indicator for the productivity at container terminals is GC productivity and since GC productivity cannot exceed the speed of physical GC operations, a Pooling System is applied to increase productivity which its meaning and effect is massive. Here in the Report, we produce the Pooling Algorithm system to improve the efficiency of the transported equipments in container terminal which is actually applying for this method and have compared Non pooling system with Pooling system in the fields. By introducing a transfer equipment pooling system and enhancing the productivity compared to other terminals, it may become an essential factor for increasing the continuous service quality and profitability in terms of terminal business.