Material Handling Operations Research Articles

Flexible material handling system for multi-load autonomous mobile robots in manufacturing environments: a hierarchical reinforcement learning approach

The increasing complexity of customer demands has led to the implementation of flexible job-shop scheduling and automated material handling systems across manufacturing sectors. In particular, advances in robotic technology have made autonomous mobile robots (AMRs) essential for material handling tasks within these sectors. The capability of free movement, path planning, and loading multiple work-in-processes (WIPs) can significantly enhance the efficiency of material handling operations. However, the full flexibility of AMRs cannot be utilised when their decisions regarding the sequence of loading and unloading multiple WIPs are made by specific rule-based operations, resulting in inefficiencies in the throughput of WIPs in manufacturing environments. To address this inefficiency, we introduce a hierarchical reinforcement learning algorithm to optimise material handling with AMRs, thereby maximising the throughput of WIPs. In this approach, a graph attention network (GAT) serves as an encoder for the hierarchical reinforcement learning (HRL) input, effectively capturing the complex relationships between different nodes. Computational experiments demonstrate that our approach enhances the efficiency of the material handling system more effectively than existing rule-based methods.

Symmetry-Enhanced LSTM-Based Recurrent Neural Network for Oscillation Minimization of Overhead Crane Systems during Material Transportation

This paper introduces a novel methodology for mitigating undesired oscillations in overhead crane systems used in material handling operations in the industry by leveraging Long Short-Term Memory (LSTM)-based Recurrent Neural Networks (RNNs). Oscillations during material transportation, particularly at the end location, pose safety risks and prolong carrying times. The methodology involves collecting sensor data from an overhead crane system, preprocessing the data, training an LSTM-based RNN model that incorporates symmetrical features, and integrating the model into a control algorithm. The control algorithm utilizes swing angle predictions from the symmetry-enhanced LSTM-based RNN model to dynamically adjust crane motion in real time, minimizing oscillations. Symmetry in this framework refers to the balanced and consistent handling of oscillatory data, ensuring that the model can generalize better across different scenarios and load conditions. The LSTM-based RNN model accurately predicts swing angles, enabling proactive control actions to be taken. Experimental validation demonstrates the effectiveness of the proposed approach, achieving an accuracy of approximately 98.6% in swing angle prediction. This innovative approach holds promise for transforming material transportation processes in industrial settings, enhancing operational safety, and optimizing efficiency.

Design and development of a not actively driven modular device for parts feeding and sorting

The current paper focuses on developing and designing a not actively driven module for material handling operations in the field of intra-logistic. This device, belonging to the class of systems known as smart surfaces, is planned to be assembled with others to create manipulative arrays. As a novel feature, the reported concept aims to generate the frictional forces required for surface operation avoiding motors and with a simplified design. The article not only presents the design of the concept, but also the analytic models used to describe its operation and handling forces. In addition, a characterization of the fundamental parameters and the validation of the mentioned analytic descriptions together with the functioning itself are reported. As result, the analysis and the measurements presented show a real solution for a not actively driven concept, along with a methodology to characterize it and predict its handling capabilities. Specifically, the validation test proved that the model is able to represent the behavior of the friction forces with relative errors mainly in the range of 10% or lower.

Ranking of Technologies for Intralogistic Bulk Material Handling Processes Using Fuzzy Step-Wise Weight Assessment Ratio Analysis and Axial-Distance-Based Aggregated Measurement Methods

The logistics network is considered the provider of logistics activities in supply chains. The fluctuating requirements of customers and the logistics network’s complex structure are only a few of the factors that cause challenges to its management. Industrial facilities are particularly vulnerable to challenges because material handling operations dominate in addition to manufacturing activities. Disruptions at industrial plants are disseminated through the logistics network, affecting all supply chain participants. As a result, reducing material handling time and costs to decrease material losses, pollution, and productivity is vital to their business. Due to their distinctive properties and significant share in finished goods, bulk materials are particularly vulnerable to issues during manufacturing. Accordingly, this study aims to rank and select technologies for handling bulk materials in an industrial plant where the production of construction materials is performed. This paper proposes four alternative solutions for the observed case study, and nine criteria were selected for the evaluation. A new hybrid multi-criteria decision-making model is proposed. The model combines Fuzzy Step-Wise Weight Assessment Ratio Analysis (SWARA), used to determine the weight of criteria, and the Axial-Distance-Based Aggregated Measurement (ADAM) method, used to rank alternative solutions. The model results indicate that the pneumatic conveyor is the best ranked alternative that significantly increases productivity, reduces losses, and improves working conditions. The key contributions of this study are its analysis of the efficiency of the technologies proposed for bulk material handling and the development and implementation of a model framework for the ranking of these technologies.

Innovations in Ergonomic Risk Assessment and Intervention in Material Handling

This review paper delves into the complex facets of ergonomic risk evaluation and reduction across various industrial sectors. The focus is on identifying the hazards linked to manual labor, especially those contributing to physical risks and musculoskeletal disorders among workers, and proposing inventive solutions to mitigate these threats. The review brings together insights from different studies, emphasizing the application of automation, virtual modeling, Kinect-based evaluations, and other innovative tools in repetitive tasks and material handling operations. It also explores the usage of back-support exoskeletons, observational checklists, and workspace redesigns to decrease risks in construction, manufacturing, vegetable transportation, clothing accessories, and other sectors. The development of risk assessment frameworks for specific roles such as container terminal operators and the examination of musculoskeletal disorders in diverse worker demographics, including older female farmers and factory workers, are also featured. The comprehensive approach of the journal sets the stage for future research, aiming to further reduce the prevalence of musculoskeletal disorders through continued innovation and cross-sector collaboration.

A Review of the Blast Fragmentation Analysis Techniques used in Surface Mines

Fragmentation refers to the process of breaking solid in-situ rock masses into smaller pieces during excavation or material handling operations. The fragment size distribution and degree of fragmentation within the blasted rock mass stand as a critical aspect for optimizing the efficiency of loading, transportation, crushing, and milling operations. The analysis of blast fragmentation analysis is done by several existing modern techniques which include the visual analysis method, photogrammetric method, and image analysis method, etc. In this study, all the blast fragmentation techniques are reviewed, and the advantages and disadvantages of all the methods are discussed. Along with that, a blast fragmentation analysis is conducted for the rock pile images of a blasting site collected from Dongri Buzurg Mine (MOIL), India using the image processing technique in WipFrag software. The feasibility of the blasting patterns is judged based on the uniformity coefficient (Cu) and the coefficient of gradation (Cg) which are found to be 4.47 and 0.94 respectively. The fragmentation for the muck pile is found to be uniform and well-graded for the blast site and the methodology used is found to be simple yet effective for the analysis.

Mobile Crane for Workshop

Abstract: In material handling, the cranes play a vital role in modern manufacturing industries. In our project we aim to fabricate a hydraulic operated floor crane for handling various kinds of materials. The hydraulic floor crane consists of mast, boom, base, lift cylinder, hand lever, hook and wheels. The hydraulic cylinder is pumped with the help of hand lever at the same time the material with the help of hook and hydraulic cylinder released to the pressure valve so the material is unloaded. The material from one place goes to the other place with the help of hydraulic floor crane. The crane reduces the worker’s fatigue and increases the overall efficiency of production process with good safety. The crane is fabricated with complete clear front, small compact frame, good reach, high lift. The crane has the capacity of lifting 250kg to half ton with wide spread application in the shop floor. Thus the floor crane would serve as a safe and versatile model for material handling operations.

A STUDY ON WAREHOUSE MANAGEMENT AND MATERIAL HANDLING PROCESS AT POLKART LOGISTICS

The structuring of your warehouse material handling system will necessitate high-level efficiency. This will entail efficient logistics for warehouse and customer requirements. Both inbound and outbound processes will be crucial to material handling. Materials handling is essentially related to warehouse management. Thus, it has a direct impact on transit time, resources usage, and service levels. Materials handling is one among the factors that made an imperative contribution to the logistics and supply chain efficiency.The inventory management plays the main role in a warehouse management. Stock audit has to be done monthly.The present study delineates the material handling operations at third party logistics warehouses. it was possible to suggest that internal customers understood that the new materials handling management system enlarged service agility and reliability and reduced costs, which caused an improvement in overall satisfaction. The main objective of this study is to identify the methods employed in the material handling department at logistics warehouses.

A Study on the Usage of Robot Navigation to Determine Robot’s Own Position in its Frame of Reference and then to Plan a Path towards Some Goal Location

In this study, the issues and opportunities can be achieved with the help of a robotic navigation system. The determination of a robotic navigational system is able to ensure the proper development of different understandings which are achieved with the help of different problems as these can solve different issues. Navigational robots are used in different fields and provide great growth in these fields which are effective and promotional developments are understood. Drones are used for different navigational improvements such as mapping which provide accuracy in the system as these are beneficial for gaining growth in goal achievement through different AI-based software systems. Secondary qualitative research is done for the completion of the research which is able to provide proper knowledge in this research in the field of robot navigation. Nowadays navigation can be easily accessible with the help of GPS systems as people are able to get the location of any place from anywhere on the internet. These facilities are ensuring proper development in the business process of companies as different businesses achieve their profitability with the help of a robotic navigational system that has gained progressive development in the research. The understanding of the robot's own location is able to develop the quality of the robot's ability which are helping to ensure planning toward the goal location. Real-time navigation is creating different ways for aiming towards navigational path planning which are helping to achieve material handling, patrolling, disaster relief, and rescue operations. Keywords : Artificial potential field, autonomous navigation, Dijkstra, extended Kalman filter, Global Navigation Satellite System, Global Positioning System, hybridization techniques, LIDAR, local navigation system, near fields communication, Robotic navigation, Vector field histograms.

Wedge-Shaped Hopper Design for Milled Woody Biomass Flow

The bioenergy industry has been challenged by unstable flow and transport of milled biomass in material handling operations. Handling issues such as hopper clogging and auger jamming are attributed to knowledge gaps between existing handling units designed for bulk solids and their suitability for milled biomass with high compressibility. This work investigates various flow behaviors of granular woody biomass in wedge-shaped hoppers. Hopper flow physical experiments and numerical simulations are conducted to study the influence of the critical material attributes and critical processing parameters on the flow pattern, arching, and throughput. The results show that (1) the preferred flow pattern, mass flow, can be achieved by controlling the material’s internal friction angle, hopper inclination, and hopper wall friction; (2) hopper arching, governed by the competing gravity-driven force against flow resistance from material internal friction and material–wall friction, can be controlled by the hopper wall friction angle and the inclination angle; and (3) flow throughput can be accurately estimated from our empirical equation with inputs of hopper outlet geometry and particle-scale to bulk-scale material attributes. This study elucidates woody biomass flow physics and provides guidance for industrial equipment design.

A two-stage solution approach for unequal area facility layout problem with bi-directional relaxed flexible bay structure

PurposeThe purpose of this article is to develop a bi-directional relaxed flexible bay structure (BRFBS) in the layout for the unequal area facility layout problems (UA-FLPs) and test the suitability of the proposed approach using literature data.Design/methodology/approachThis research adopts a two-stage solution approach for UA-FLPs to form BRFBS in the layout. The solution to UA-FLPs is carried out in discrete space. The proposed heuristic method optimises the layout plan for minimising the material handling cost (MHC), and also, it indirectly optimises the space utilisation by reducing the empty space in the layout. The first stage of layout design assumes that all facilities are equal in size and uses quadratic assignment problem (QAP) model. QAP is solved with a simulated annealing heuristic method. In the second stage, a heuristic method is proposed to find the optimum width for each bay and the dimension for facilities. The proposed heuristic method is tested with numerical data available in the literature. Results are compared with the results obtained by layout planning software, and with the simulated annealing algorithm for flexible bay structure (SA-FBS) heuristic procedure for continuous space UA-FLPs.FindingsThe proposed two-stage solution approach gives the BRFBS for the UA-FLPs. BRFBS helps to create proper aisle structure in the layout plan. The layout configuration and solution of the proposed method is better than the layout planning software solution and SA-FBS solution. The application of the proposed heuristic method to case data gave lesser MHC, better space utilisation and better aisle formation than the existing layout.Research limitations/implicationsThe proposed approach has the limitation that it can be applied only to UA-FLPs solved in discrete space. When the UA-FLPs are solved in continuous space, then it is not possible to make application of this approach to form bi-directional relaxed flexible bays in the layout plan.Practical implicationsMost of the modern industries are automated, and they use material handling equipment (MHE) like automated guided vehicles (AGVs). Design of layout plans that help to create proper aisle structure for AGV’s in the layout plan is a challenging to the researchers. The BRFBS configuration is more suitable in the flexible manufacturing system where AGVs are used for material transportation.Originality/valueThis paper proposes a novel two-stage heuristic method for solving the UA-FLPs in discrete space. The proposed approach generates a BRFBS in the layout plan. The BRFBS helps to create a proper aisle structure suitable for better material handling operations. Hence, this type of layout helps in easy interaction of the MHE (e.g. AGVs) with the boundaries of the facilities touching the aisle.

Strategy for the introduction of autonomous driving technologies: a case study in the logistics area of an automotive company

These days, due to the emergence of Industry 4.0, it is possible to notice a growing interest among companies in automating their processes. Autonomous driving technologies are generating increasing interest in carrying out material handling operations, being clear that these technologies allow companies to have greater flexibility, higher accuracy, lower costs, and higher productivity. What is not clear is how to implement these autonomous driving vehicles, which raises questions such as: What are the requirements to consider when using autonomous transport to move materials in the shopfloor? What are steps must be taken to introduce autonomous driving technologies in an industrial environment?This article, which describes a case study carried out in an automotive company, provides the answers to these questions, as well as presents a methodology to implement Autonomous Guided Vehicles (AGVs), being a relevant contribution to the understanding and implementation of AGVs in the industrial context. During the case study, the number of AGVs required was estimated (by analytical method and using SIMIO simulation software), and an economic feasibility study of the project was also performed.

Regenerative Belt Conveyor versus Haul Truck-Based Transport: Polish Open-Pit Mines Facing Sustainable Development Challenges

The mining industry is facing sustainable development challenges, among which the energy efficiency issues seem to be of major importance. As transport of the mined ore is considered as one of the most energy intensive operations, the improvement of its energy efficiency is a key indicator in terms of sustainable actions taken by mining companies. In open-pit mines, the material handling operations are mostly performed with trucks. Their electrified version—truck trolley systems—surpass diesel trucks’ efficiency while comparing the increased production capacity and the reduction of maintenance cost and fuel consumption. The paper analyzes the opportunities and benefits of the replacement of an ore transport system based on hauling trucks with a regenerative belt conveying in an open-pit mine. Presented case study has been analyzed from energy consumption and environmental impact reduction perspectives. Generally, conception of a regenerative conveyor is based on recuperation of energy or continuous braking needed while a conveyor is running downhill. Energy generated during the braking process (converted from the potential gravitational energy of the conveyed material) is fed back to the electrical grid. Then the regenerative conveyor can be considered as a machine that mines energy as an additional by-product of an exploited deposit. It was shown that difference in transportation cost between haul trucks and energy efficient regenerative conveyors is around 95%. The paper points the conditioning elements to allow the implementation of a regenerative belt conveyor system.

The effectiveness of ergonomic interventions in material handling operations

This study evaluated the effectiveness of ergonomic interventions in material handling operations involving 33 employers and 535 employees from 2012 to 2017. Outcomes included employee-reported low back/upper extremity pain and safety incidents at baseline, every three months, and annually for up to two years. A total of 32.5% of employees completed at least one survey, while 13.6% completed all nine surveys over two years. Among highly exposed employees (who reported handling >= 50 lbs. > 33% of the time), upper extremity pain frequency and severity were lower among those who reported using the intervention routinely versus those that reported using their body strength alone to handle objects >= 50 lbs. After excluding from analyses one employer that used anti-fatigue mats, low back pain frequency was also significantly lower among highly exposed intervention users. In conclusion, there was some evidence that the interventions were effective in reducing employee-reported pain for highly exposed employees.

Sustainable Scheduling of Material Handling Activities in Labor-Intensive Warehouses: A Decision and Control Model

In recent years, the continuous increase of greenhouse gas emissions has led many companies to investigate the activities that have the greatest impact on the environment. Recent studies estimate that around 10% of worldwide CO2 emissions derive from logistical supply chains. The considerable amount of energy required for heating, cooling, and lighting as well as material handling equipment (MHE) in warehouses represents about 20% of the overall logistical costs. The reduction of warehouses’ energy consumption would thus lead to a significant benefit from an environmental point of view. In this context, sustainable strategies allowing the minimization of the cost of energy consumption due to MHE represent a new challenge in warehouse management. Consistent with this purpose, a two-step optimization model based on integer programming is developed in this paper to automatically identify an optimal schedule of the material handling activities of electric mobile MHEs (MMHEs) (i.e., forklifts) in labor-intensive warehouses from profit and sustainability perspectives. The resulting scheduling aims at minimizing the total cost, which is the sum of the penalty cost related to the makespan of the material handling activities and the total electricity cost of charging batteries. The approach ensures that jobs are executed in accordance with priority queuing and that the completion time of battery recharging is minimized. Realistic numerical experiments are conducted to evaluate the effects of integrating the scheduling of electric loads into the scheduling of material handling operations. The obtained results show the effectiveness of the model in identifying the optimal battery-charging schedule for a fleet of electric MMHEs from economic and environmental perspectives simultaneously.

Naval Supply Systems Command Change Management Support Solicitation: Bid or No-Bid (A)

Cowan and Associates (C&A) provided strategic planning, business planning, change management, performance measurement, and knowledge management support to various Navy commands. Its managing director, Jeff Pottinger, was contemplating a Request for Proposal to provide change management support services to the Naval Supply Systems Command (NAVSUP) in Mechanicsburg, Pennsylvania. Pottinger was intimately aware of the significant change management challenges facing NAVSUP through his experience with several previous contracts supporting NAVSUP, and he knew his company had the capability to support its requirements. He was meeting with C&A's founder and president and its CFO to discuss this opportunity and whether to devote scarce resources to writing a winning proposal. Excerpt UVA-S-0222 Rev. Mar. 18, 2020 Naval Supply Systems Command Change Management Support Solicitation: Bid or No-Bid (A) Jeff Pottinger sat in his office in Arlington, Virginia, contemplating the Request for Proposal (RFP) in his hands. Here was an opportunity to provide change management support services to the Naval Supply Systems Command (NAVSUP) in Mechanicsburg, Pennsylvania. Pottinger had retired out of NAVSUP in 2001 after serving 24 years of commissioned service. As a Supply Corps Officer, he had gained extensive leadership, logistics, and financial management experience, in both his sea and shore assignments. His logistics assignments had included positions in transportation, warehousing, material-handling operations, inventory management, and operational logistics. After retiring, Pottinger had spent a year with a large DoD consulting firm before going to work for a big-box electronics retailer, overseeing a two-state district of eight retail stores with $ 100 million in annual sales. Pottinger joined Cowan & Associates, Inc. (C&A) in late 2005 and for the past six years had provided strategic planning, business planning, change management, performance measurement, and knowledge management support to various Navy commands. Additionally, Pottinger provided executive education support to the Darden Graduate School of Business Administration and the Naval Postgraduate School. As managing director of the firm, he played a key role in determining which opportunities the company would pursue, coordinating the company's response to key proposals (especially those for strategic customers), and determining how the company would execute a contract it had won. . . .

Overhead Travelling Crane Construction Deflection Measurements with Telematic Approach

Abstract Transport has always been a fundamental impulse for the development of civilization. Issues related to the regularity of operation of technical systems, in the last decade have become important issues being considered from both the point of view, as well as economics. Today the major threat in the operational reliability constitutes intensification of the machine and equipment use leading to excessive degradation. In automated manufacturing processes where the material handling operations are realized by the cranes, the safety as both devices and operating people constitute important factor. The main purpose of the article was focused on the set of issues including the material handling devices (MHD) reliability shaping problem especially presents work in progress towards development the MHD condition assessment system with using telematic approach. In the article author, special care was enclosed to MHD devices with strength human factor interaction and relatively large construction, so the overhead travelling crane was chose. The object of the statement constitutes an attempt of collecting the knowledge concerning a possibility of use modern measurement systems to monitoring crane bridge deflection. All tests and considerations were conducted on the double girder overhead travelling crane with hosting capability 1000 kg and bridge span 8000 mm.

Warehousing and Material Handling Practices in Ghana: A Tale of Tradition and Modernity

The paper investigates warehousing and material handling practices in the civil service of Ghana. The purpose is to ascertain the level of transition from fully manual operations to the integration of technology in warehousing and material handling operations in selected Metropolitan, Municipal and District Assemblies (MMDAs). Data were collected from 40 MMDAs cross the current 10 regions of Ghana. The study noted among others that, most warehouses lacked basic mechanical equipment for effective and efficient operations. Warehouse automation was completely non-existent in all selected Assemblies. In the case of material handling, the research discovered that very little effort has been made to equip employees with the requisite handling equipment for the execution of tasks. The study further revealed that there was virtually no in-service training on effective material handling practices in the civil service of Ghana. Indeed, practitioners most often use their bare hands and feet in handling all forms of materials including hazardous chemicals. The study also indicated that, on few instances where some handling and protective equipment were made available, most employees refused to use them citing reasons that bother on culture and tradition. The study concludes that it is imperative for authorities to put in place policies to protect practitioners in the execution of tasks. Thus, there should be an efficient change management system to ensure a gradual paradigm shift from obsolete warehousing and material handling practices to a much-integrated system where aspects of manual, mechanical and automated systems are combined.

Multi-load AGVs scheduling by application of modified memetic particle swarm optimization algorithm

The automated guided vehicles (AGVs) are extensively applied for material handling operations in the flexible manufacturing system (FMS) facilities. The scheduling decisions for the multi-load AGVs serving in the FMS with minimum travel time, waiting time and time to serve jobs are highly significant from the sustainable profits point of view. The present study proposes a combination of particle swarm optimization (PSO) for global search and memetic algorithm (MA) for local search termed as the modified memetic particle swarm optimization algorithm (MMPSO) for scheduling of multi-load AGVs in FMS. The newly proposed algorithm is applied for the generation of initial feasible solutions for scheduling of multi-load AGVs with minimum travel and minimum waiting time in the FMS. From the computational experiments, it is observed that the proposed MMPSO algorithm performs an effective and efficient exploration and exploitation process and further yields promising results for the multi-load AGVs scheduling problem in the FMS facility.

A dynamic scheduling approach for optimizing the material handling operations in a robotic cell

This paper investigates a real-time dynamic job-shop scheduling problem in a robotic cell, in which multiple jobs enter into the cell with unexpected arriving rates. Different from classical flow-shop and job-shop scheduling problems, the jobs’ transportation handled by a robot must be considered. Another characteristic is that the jobs’ processing times are not constant values but confined in time-window constraints. To efficiently solve this problem in real time, the original schedule is restricted to zero changes. The problem is formulated as a sophisticated Mixed Integer Programming (MIP) model in which the new jobs’ processing and transportation operations are inserted into the available time intervals of the original schedule. To strengthen the MIP model, speed-up constraints are added by taking advantage of specific relationships between the available time intervals arranged for a job's processing and transportation operations. Furthermore, an exact iterative algorithm is proposed, which starts with a relaxed solution of the MIP model and iteratively adds essential robot handling capacity constraints back to the relaxed MIP model until an optimal solution is found. Computational results validate effectiveness and efficiency of the strengthened MIP model and the iterative algorithm.