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Experiment folder for optimization shows the different best designs identified over the course of the optimization and the log

Experiment folder for optimization shows the different best designs identified over the course of the optimization and the log

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Article
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Even though order picking is the most costly operation in a warehouse, current design practices have used the same principles (straight rows with parallel pick aisles and perpendicular cross aisles) to reduce travel distances between pick locations for more than sixty years. We present an open-source computational software system for facilitating t...

Citations

... Large businesses may afford designed-for-purpose warehouses [4][5][6][7][8], use picking strategies suitable for large throughput [9][10][11], including combined strategies [12], and invest in automation, such as the use of autonomous mobilerack vehicles [13], robotics [14][15][16], and automated guided vehicles to support human order pickers [17]. However, smaller businesses may need to adapt existing, irregularlyshaped, building space [18]. ...
... Each edge connects neighboring graph nodes that are either end points or points of intersection in the warehouse. For example, the green way in Fig. 2 consists of three edges: from point (0,7) to point (5,7), from point (5,7) to point (5,4), and from point (5,4) to point (0,4). In bidirectional ways, each pair of nodes is connected by two edges with opposite directions. ...
Article
This work presents a procedure to plan the storage, picking sequences, and picking paths in warehouses, focusing on small businesses that may not afford the construction of designed-for-purposes storage facilities or use sophisticated picking strategies. The procedure considers storage spaces of irregular shapes and assumes the use of a picker-to-parts strategy. It considers constraints, such as proximity constraints and comprises three nested loops. The innermost loop uses the NetworkX package to find the shortest path between two locations. The intermediate loop uses the traveling salesperson problem implementation of Google OR-Tools to find the optimal path to collect the items in a given order. The third loop uses the simulated annealing method for optimal storage allocations. A class-based approach to simulated annealing optimization proposed in this work systematically improves the storage/picking configuration.
... Important research for the storage layout definition considering the relation between the orders and SKUs characteristics to minimize the tardiness and the total distance traveled by pickers was proposed by Wutthisirisart et al. [145]. The most current research for facilitating the design of WAs layouts is the computational software system (that considers the routes average distance as the objective function) presented by Ozden et al. [100]. This software is open source available on a GitHub (https://github.com/) ...
Article
Literature has shown expressive demands for Picking Optimization Methods (POMs) that are better suited to the manual picking systems and Warehouses (WAs). There are still many gaps and trade-offs between the level of customer service and the WA efficiency for the so-called Joint Order Batching, Assignment and Sequencing, and Routing Problem (JOBASRP). Thus, the objective of this manuscript is to provide a literature review on the POMs proposed for the JOBASRP in WAs that deal with low-level picker-to-parts systems together with the order due dates and Stock Keeping Units. In the total of analyzed manuscripts (from 1960 to 2021), metaheuristics together with constructive heuristics obtained the best solutions for the JOBASRP. The most used technique is the Genetic Algorithm (50 %), followed by the Variable Neighborhood Search (40 %) and Iterated Local Search (10 %). The main performance indicators are Total Picking Time, Tardiness in Customer Orders and Computational Processing Time for POMs. In addition, we present a reflection focused on the main gaps, trade-offs, and prospects for improving the level of adaptation and performance demanded for the POMs. This manuscript provides eminent contributions to WAs management theory and practice and to the application of the so-called POMs. The theoretical framework presented summarizes the state of the art, defining the basic guidelines regarding new research opportunities, and supporting managers, students, and researchers in the optimization processes and decision making in WAs. We conclude that broader views on adaptation taxonomies and multi-objective algorithms will guide the integration between different areas of the WAs and the development of better POMs.
... Kocaman et al. 34 investigated the best layouts with arbitrary angles of picking and crossing aisles in a continuous space for single-command travel. Ozden et al. 35 proposed an open-source warehouse layout system that automatically generates and evaluates layout designs for warehouses, using the average walking distance of the picker as the objective function. Non-traditional layouts provide new ideas and methods for the rational design of warehouse layouts. ...
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In order to improve the picking efficiency of warehouses, shorten the time cost and promote the development of the logistics industry, this study analyzes the routing strategies in fishbone layout warehouses under the class-based storage strategy. The fishbone layout was divided into three storage areas for class A, class B, and class C items according to the proportion using the straight line, to meet the classification requirements of items. Under the class-based storage strategy, to evaluate the performance of the return routing strategy and the S-shape routing strategy, the stochastic models of the expected walking distance of the two routing strategies in the fishbone layout warehouse are established by calculating the sum of the expected walking distances in diagonal cross-aisles and picking aisles. Finally, the stochastic models of the two routing strategies are simulated and verified, and the impacts of the two routing strategies on walking distances are analyzed by comparing the expected distances under different ordering frequencies and space allocation strategies. The numerical results show that the return routing strategy has an advantage over the S-shape routing strategy when determining the relevant parameters of the fishbone layout and picking orders. Meanwhile, it also provides a theoretical basis for research on stochastic models of routing strategies in fishbone layout warehouses under the class-based storage strategy.
Article
Full-text available
Purpose: This article aims to show the methods used to optimize layout and tools that have been applied since 2010 in the most diverse production environments. Theoretical Reference: Due to the intense competitiveness and uncertainties in the current market, improving processes and increasing production efficiency by managing the layout of a facility can be one of the methods to benefit organizations. In this context, knowledge of the main tools and methods is essential in defining the conduct of studies. Design/methodology/approach: Research was carried out through a systematic literature review. The databases used were Science Direct and Portal Capes. Using keywords, a defined scope and the relevance of the theme, international articles were selected for reading and discussion. Findings: Through the review, it was possible to select 51 articles which were relevant to the topic. Due to the complexity of the layout management study, it was found that increasingly more algorithms, mathematical and computational models are being used to solve these NP-hardness problems. Research, Practical & Social implications: adjusting to new methods and ways of solving problems laying out facilities, although scenarios can be extremely varied, they can improve business results by making the process more efficient. Originality/value: The article compiles and briefly explains the methods found to optimize the layout, which is of great importance considering the knowledge that these models spread on production management practices. Keywords: Layout optimization. Algorithm. Method. Facility layout planning