International Journal of Manufacturing Research (24 papers in press)
Automatic Identification of Mechanical Parts for Robotic Disassembly Using the PointNet Deep Neural Network
by Senjing Zheng, Feiying Lan, Luca Baronti, Duc Pham, Marco Castellani
Abstract: This paper presents a study on the identification of objects from 3D scenes (point clouds) of mechanical components of automotive devices, using the PointNet deep neural network. PointNet was trained to recognize twelve parts of models of engine turbocharger. The twelve instances included different types of parts, as well as different models of the same part. The PointNet was trained using partial images of the objects generated from CAD models, and tested on unseen examples. Experimental trials indicated that PointNet is able to recognise with accuracy the mechanical parts, and that its learning procedure is consistent and effective. In presence of sensor imprecision, the accuracy in the recall phase can be increased adding stochastic error to the training examples. The possibility of training twelve independent classifiers to be employed separately or in one ensemble classifier was investigated. The results were comparable to those obtained using one classifier for all parts.
Keywords: Remanufacturing; Disassembly; Automotive; Machine Vision; Point Clouds; Deep Neural Networks.
Exact and Meta-heuristic Approaches for the Single-machine Scheduling Problem with Flexible Maintenance under Human Resource Constraints
by Meriem Touat, Benbouzid-Sitayeb Fatima, Belaid BENHAMOU
Abstract: This paper tackles the scheduling problem of both production and flexible preventive maintenance activities on a single machine under human resource constraints. The considered human resources oversee the maintenance activities. They are characterized by a competence level and a timetabling that determines their availabilities. Our objective is to minimize a common and weighted objective function that involves both the tardiness and the earliness resulting from production and maintenance activities when considering maintenance workers. We first introduce a mathematical modeling for the studied problem that we implemented in Cplex in order to compute the optimal solutions of small instances of this problem. Secondly, we propose an improved Guided Local Search (GLS) metaheuristic to deal with relatively large instances of the problem. Cplex is used as a reference exact method to check the solution quality of the approached method GLS. The proposed methods are evaluated on a large number of randomly
Keywords: Single machine scheduling; Flexible maintenance planning; Mathematical modeling; Guided Local Search; Human resource constraints.
Efficiency evaluation of Manufacturing firms in China. The case of Patent-Intensive Industries
by Oswin Aganda Anaba, Mingxing Li, Zhiqiang Ma, Jialu Su, Benjamin Azembila Asunka
Abstract: In an environment where there is a consistent change in the flow of innovation improvement, the advancement of innovation and technology has turned into an inevitable subject of present day enterprises, yet there exists little knowledge about their efficiency from the view point of patent-intensive industries The level of technological innovation efficiency of patent-intensive industries has an effect on the industrial structure and industrial competitiveness This paper therefore evaluates the technology innovation efficiency of Chinas patent-intensive industries using the two-stage non-parametric Data Envelopment Analysis (DEA) over the period of 2006
Keywords: patent-intensive industries; technological innovation; efficiency evaluation; two-stage DEA model.
Rapid Casting using Alternative Approach of Pattern and Mold Making
by Ranjeet Kumar Bhagchandani, K.P. Karunakaran, Pushkar Kamble, B. Ravi, Sajan Kapil
Abstract: Evaporative Pattern Casting (EPC) process facilitates the production of parts with complicated geometries. Two major problems associated with EPC are the fabrication of the metal tooling and complicated mold preparation. To overcome these limitations, a novel Rapid Foam Casting (RFC) process is proposed. The complicated pattern geometries as selected on the basis of shape complexity are produced by the authors developed Rapid Prototyping machine namely Segmented Object Manufacturing. Patterns are then converted into metallic castings by adopting two alternative molding processes for EPC i.e. no-bake and green sand molding. Taguchis orthogonal array is used for the design of experiments to investigate the effect of the part geometry, pattern density and molding method on surface finish and dimensional accuracy of the casting. Analysis of variance (ANOVA) is also performed to find out the individual participation of each factor on the surface finish and dimensional accuracy of the casting.
Keywords: Rapid Foam Casting; Rapid Prototyping; Evaporative Pattern Casting; Segmented Object Manufacturing; Expanded Polystyrene.
Exploiting the Drill Cutting Lip to Quantify the Contributions of Process Parameters To Cutting Pressures - A Response Surface Analysis
by Charbel Seif, Ramsey Hamade, Ilige Hage, Re-Mi Hage
Abstract: This work exploits the characteristically complex geometry along the lip of a chisel drill. Few dry drilling experiments are conducted on aluminium 6061-T6 workpieces pre-cored with holes of diameters ranging from 25% to 75% of the drill diameter. Based on the generated torque and thrust force drilling profiles, incremental tangential, Ktc, and normal, Knc, cutting pressures values are assigned to the radial position of each cutting lip element. The resulting pressures amounted to a large number (192) of equivalent oblique turning tests with each edge possessing individual cutting parameters of uncut chip thickness, cutting speed, normal rake angle, and oblique cutting angle, Statistical analyses were performed on collected data. Sensitivity of the found cutting pressures with respect to cutting parameters is validated against literature-reported findings based mainly on turning tests. The findings support this works approach of employing drilling as a data collection tool in lieu of orthogonal cutting experiments.
Keywords: drilling; cutting pressures; response surface design; data analysis.
A Modeling and Semantic Description Method of Cloud 3D Printing Order Task Ontology Based on Multidimensional Features
by Chenglei ZHANG
Abstract: Aiming at the demands of unified modeling and standardization description of Cloud 3D Printing order tasks which are heterogeneous, multidimensional, semantic and other characteristics in Cloud manufacturing environment, based on Web Service and Semantic Web Services, a semantic description and encapsulation method of 3D Printing order tasks is studied. It includes: proposes a modeling and semantic description method of Cloud 3D Printing order task ontology Based on multidimensional features. Through the this features of Cloud 3D Printing order resources, the attributes of Cloud 3D Printing order tasks are decomposed them into atomic tasks according to the purpose of order tasks; the Cloud 3D Printing order task meta-data ontology modeling method and service packaging technology are studied, and then the feasibility of the method is verified by an example of Cloud 3D Printing order task semantic description model.
Keywords: Multidimensional Features · Order Task · Web Services · C3DP · Semantic Description · Meta-data.
Flow field analysis of the measuring stability of the head of a pneumatic measuring instrument
by Xianjie Wei, Wei Long, Pu Ren, Wei Deng
Abstract: The existing air gauge structure often exhibits instability in measurement values, and the workpiece measurement process is prone to wear, thereby affecting the measurement accuracy and scope of the use of air gauges. Based on the principle of pneumatic measuring instruments, in this work, calculation results of the flow field between the large hole of the connecting rod and the probe are compared with measured results. It is found that the supporting air film at the guide surface of the existing probe is not complete and the airflow in the exhaust groove is disordered, thereby leading to the poor stability of the measurement process. Via further analysis of the flow field pressure, it is found that the edge of the exhaust groove near the end face of the nozzle will produce a local high-pressure zone, which will lead to the increase of the gas resistance and affect the measurement accuracy.
Keywords: pneumatic gauge; engine connecting rod; flow field stability; exhaust groove; gas resistance coefficient.
Emergency order replacement of substandard products under economic production quantity model, including shortages and backordering
by Harun Öztürk
Abstract: This paper concerns inventory control under the economic production quantity model, allowing for substandard products and shortages The imperfect manufacturing system creates a percentage of substandard products, treated as a random variable having a known probability distribution function All products produced are screened to identify substandard products. Restrictions such as production programming may make it impossible to rework substandard products, but the manufacturer has the option of replacing them by purchasing products of good quality from a domestic supplier, though these will normally have a higher unit cost. Three possible cases can occur, depending on the timing of adding emergency-purchased products to the inventory. The paper presents a numerical example and a sensitivity analysis to show how the three cases are applied within the proposed inventory model.
Keywords: inventory; economic production quantity; substandard products; shortages; reduced price; emergency purchase.
Dynamic seru order acceptance and scheduling with periodic worker assignment
by Zhe Zhang, Lili Wang, Yong Yin
Abstract: In this paper, we examine the dynamic seru order acceptance and scheduling problem with periodic worker assignment. To deal with the dynamic order arrival environment, a periodic dynamic adjustment strategy combined the technology of rolling window will be adopted. In other words, we periodically accept, schedule the coming orders and reassign workers in a periodic manner to decompose the dynamic problem into a series of continuous static sub-problems to maximize total net revenue. At the same time, an extended bi-level chromosome coding genetic algorithm combining order acceptance and scheduling results with worker assignment is designed which automatically constructs reactive adjustment strategy for the dynamic order acceptance and scheduling with worker assignment. In the end, the experimental results show that the improved genetic algorithm with rolling window technology (IGA-RWT) is feasible and effective.
Keywords: seru production system; order acceptance and scheduling; rolling window technology; worker assignment; improved genetic algorithm.
Determining favourable process parameters in Computer Numerically Controlled polishing of metal surfaces
by G.-C. Vosniakos, Panagiotis Avrampos, Theodore Mitropoulos
Abstract: Traditionally, metal surface polishing has been an important high precision process that has mostly been carried out manually, due to its high complexity and the difficulty in controlling many process parameters simultaneously. In this work a prototype polishing jig that offers elementary force control capability is utilised in order to perform flat metal surface polishing experiments based on trochoid toolpaths. The goal of this study is to optimise polishing speed, feed rate and force levels by designing Taguchi experiments and implementing subsequent ANOVA for three successive polishing stages (grinding, lapping and finishing) while following a certain polishing method (tool and diamond paste combination), which is standard knowledge contributed by domain experts. The Taguchi approach ultimately fine-tunes the polishing procedures, ensuring that the results are both consistent and optimal, the pertinent criterion being the roughness of the polished surface.
Keywords: polishing; Taguchi experiments; ANOVA; polishing rings; abrasive; jig; trochoid; toolpath.
A Genetic Algorithm for Designing an Integrated Cellular Manufacturing System Considering a Linear Double-Row Layout
by Mohammad Nagahisarchoghaei, Morteza Nagahi, Hamed Sharifi, Javad Rezaeian, Iraj Mahdavi, Mohammad Mahdi Paydar, Raed M. Jaradat
Abstract: To design an integrated cellular manufacturing system, cell formation (CF), cellular layout (CL), and cellular scheduling (CS) need to be determined efficiently. In this study, we propose a theoretical model for designing a cellular manufacturing system that will optimise the total completion time by making these three interrelated decisions concurrently. In the theoretical model, linear single-row and double-row cellular layouts were applied, and a genetic algorithm (GA) to solve real-sized problems was developed and tested. The results of the study indicate that the proposed model with the linear double-row layout provides more reliable results than the single-row layout, and the GA achieves acceptable solutions in a more reasonable time period compared to the traditional solution method.
Keywords: cellular manufacturing; cell formation; linear double-row layout; group scheduling; genetic algorithm.
Characteristics of Cross-Wire Welding Process Used for Welded Wire Mesh
by Huanbo Cheng, Xin Zhang, Xin Wang, Yancheng Zhu, Yu Sun, Jie Zhang
Abstract: Cross-wire welding of welded wire mesh was a complex process of interaction among thermal, electrical and mechanical field. The quantitative analysis of its welding characteristics was a difficult problem. The article presented a direct coupling analysis method of thermal, electrical and mechanical fields. The welding model was simplified to be used for simulating the actual working conditions of high temperature, strong pressure and high current. The cross-wire welding characteristics of welded wire mesh was investigated. The optimum combination and prioritisation of welding process parameters were obtained by using range analysis method, which provides reference for the selection of cross-wire welding process parameters in the actual production.
Keywords: cross-wire welding; projection welding; welding characteristic; quantitative analysis; direct coupling simulation.
A Framework for Planning a Reconfigurable Assembly System for Press Brake Production
by Olayinka Olabanji, Khumbulani Mpofu
Abstract: This article presents the design of a framework for the development of a reconfigurable assembly system (RAS) to facilitate the assembly of press brakes varieties. A consideration of press brake varieties is achieved by examining the parts taxonomy of press brakes from which a framework for assembly process plan is developed that considers all the types of press brakes identified from the classification. Also, a layout for the RAS is developed by considering a prototype of the major enabling equipment of the system which is a reconfigurable assembly fixture (RAF). The development of the assembly process plan and layout of the RAS enabled the design of a reconfiguration model for operation in the RAS. The designed assembly framework will provide; rapid and physical reconfiguration of the RAF in the RAS, generation of assembly sequence for press brake varieties and allocation of assembly operations to assembly work cells in the system.
Keywords: assembly planning; press brakes; reconfigurable assembly fixture; reconfigurable assembly system.
Computational Modeling of SLM Additive Manufacturing of Metals
by Shubham Chaudhry, JAMES WILLIAM TCHEUMANAK CHUITCHEU I.V. TCHOUAMBE, Azzeddine Soulaimani, Rajeev Das
Abstract: Additive manufacturing (AM) is a technology that can create 3D structures by depositing or melting material in a layer-by-layer manner. This paper focuses on the metal-based powder bed fusion AM approach, specifically the selective laser melting (SLM) technique. The repetitive hot and cold cycles associated with AM cause localised compression and tension giving rise to significant residual stresses, which can lead to shape loss, structural failure, etc. Numerous parameters determine the thermal gradient; these include the thermal characteristics of the powder, the bed temperature, and the part size. This investigation describes the associated problem formulation and numerical resolution in the SLM simulation. An ANSYS-additive model is developed to determine the parameter dependence on the process. An efficient parameter calibration algorithm is proposed to generate an accurate numerical model. Three numerical studies are conducted using a vertical prism, a horizontal prism, and an L-shaped structure also compared with the experimental data.
Keywords: selective laser melting; SLM; simulation; additive manufacturing; ANSYS-additive.
A review: Finishing technologies of parts made by metal powder-bed additive manufacturing
by Li Liu, Guilian Wang, Jie Liu, Minke Cai
Abstract: Metal powder-bed additive manufacturing (AM) is known to possess good application prospects in the aerospace, medical and other fields. However, the furnishing of the surface quality of the AM parts is poor, and post-processing is required to meet the high applicability. Finishing processing is the main link in the post-processing for high-performance AM parts. In this report, the applications of machining, laser polishing, chemical and electrochemical polishing, abrasive flow machining and other typical finishing techniques used in the finishing of metal powder-bed AM parts are reviewed. Additionally, the evolution of surface roughness, material removal and residual stress of workpieces with different materials, different manufacturing processes (SLM, EBM, etc.) and different structural forms during the finishing process were analysed. An efficient and precise finishing technology can obviously improve the surface quality of the AM metal parts, which can be of great significance for the diverse applications of AM parts and reduce the costs.
Keywords: finishing technologies; additive manufacturing; metal parts; powder-bed.
A Batch Scheduling and Operator Assignment Model with Time-Changing Effects to Minimise Total Actual Flow Time
by Dwi Kurniawan, Andi Cakravastia, Suprayogi Suprayogi, Abdul Hakim Halim
Abstract: This paper investigates integrated problems of batch scheduling and operator assignment with time-changing effects due to the operators experiencing different degrees of learning and forgetting, and accumulating different degrees of fatigue. Each batch will be processed through a number of operations in a flow shop, where each operation can be performed by one of the alternative operators. Each operator will be assigned to a maximum of one machine, and a minimum of one operator will be assigned to each machine. The production process could produce a number of defective products that can be reworked. The problems are formulated in a model, and the decision variables are operators assignment to machines, the number of batches, batch sizes, items allocation to batches, and the schedule of the resulting batches. A proposed algorithm is developed to solve the model, and numerical examples show that the model and the algorithm work effectively for the investigated problem.
Keywords: batch scheduling; operator assignment; learning-forgetting; fatigue-recovery; actual flow time.
Prediction Model of Cutting Force in Micro-milling Single Crystal Copper
by Xiaohong Lu, Yihan Luan, Xiangyue Meng, Jianhui Feng, Steven Y. Liang
Abstract: Micro-parts of single crystal copper have been widely used in the fields of precision instruments and electricity, but little research has been done on the prediction of micro-milling force for single crystal copper. The accurate prediction of micro-milling force is the basis of studying the cutting process and tool wear. Experiments of micro-milling single crystal copper are carried out. Based on the experimental results, the effects of spindle speed, feed per tooth and axial cutting depth on the micro-milling force are analysed by using control variable method and Taguchi method. Based on the orthogonal experimental results, micro-milling force prediction models of three crystal orientations of single crystal copper are established. The exponential empirical formula between cutting force and cutting parameters is built. The coefficients of the formula are estimated by least square method. The experiment shows that the biggest relative errors are 29.38%, 32.09%, 30.30%, respectively. The average relative errors are 17.15%, 17.48%, 16.84%, respectively. Experiment verifies the validity of the model and provides a basis for subsequent single crystal materials research.
Keywords: single crystal copper; micro-milling; cutting force; crystal orientation.
Improvement of Lean Manufacturing approach based on MCDM techniques for sustainable manufacturing
by Hichem Aouag, Soltani Mohyiddine
Abstract: The purpose of this paper is to propose an improved lean manufacturing approach to enhance the sustainability performances of manufacturing processes. To do that three phases are proposed. The first phase aims to propose an extended value stream mapping method to quantify the sustainability indicators and assess the manufacturing process. Secondly, entropy method is used to determine the weights of indicators. Finally, the weights obtained from entropy method are used in fuzzy evaluation based on distance from average solution (EDAS) and fuzzy technique for order preference by similarity to the ideal solution (TOPSIS) to rank a set of kaizen events according to their ability to improve the sustainable indicators. The novelty and the main contributions of the proposed approach are proved by the development of an extended VSM method. Also, the proposed approach contributes by a new methodology for enhancing the application process of the conventional lean manufacturing approach.
Keywords: value stream mapping; VSM; lean manufacturing tools; entropy; fuzzy logic; evaluation based on distance from average solution; EDAS; TOPSIS; sustainable manufacturing.
A hybrid GA-PSO algorithm for seru scheduling problem with dynamic resource allocation
by Ling Shen, Zhe Zhang, Xiaoling Song, Yong Yin
Abstract: : As a new type flexible production mode, seru production is widely used in Japanese enterprises to deal with the manufacturing market with volatile and diversified demand. In practical seru production, product processing time may be related to resource allocation, i.e., more resource allocation, less processing time. Thus, this paper attempts to solve seru scheduling problems with dynamic resource allocation, along with which the learning effect of workers is also considered. A combinatorial optimisation model is proposed to minimise the makespan, and a hybrid GA-PSO algorithm with nonlinear inertia weight is specifically designed to solve the proposed model. Finally, a numerical example is presented to verify the effectiveness of hybrid algorithm. The computational results indicate that hybrid GA-PSO algorithm is efficient, and dynamic resource allocation should be considered in seru scheduling problems.
Keywords: seru scheduling; GA-PSO; dynamic resource allocation; learning effect.
Analysis of the Synergistic Integration of DFMT with CAPP and MP in Metal Parts Manufacturing based on Cost Analysis and Systematic Algorithm
by Omar Al-Shebeeb, Bhaskaran Gopalakrishnan, Kenneth R. Currie, Thorsten Wuest, Todd Hamrick
Abstract: This research focused primarily on self-fastening characteristics, standardisation of parts and minimal use of fasteners. The work investigated the significance of synergistic design for manufacturing techniques (DFMTs), with their inherent machine element systems (MES) and machining parameters (MPs) to evaluate which DFMT has the most influence on cost reduction and increasing throughput and under which circumstances. In sum, this research applies DFMT to product design. For each DFMT and associated MES and MP, process planning was used effectively with computer aided process planning (CAPP) tools to enhance the evaluation impact of the dialogue between the design and manufacturing functions. A systematic algorithm was inherently developed and incorporated into the software tools used herein. Generative process planning software is used to measure and analyse sensitivity in plan effectiveness. The final results showed a significant improvement in cost reduction and production rates. DFMTs 1 and 2 have the main influence on the systematic algorithm.
Keywords: design for manufacturing; computer-aided process planning; machining parameters; machine element systems; MES; process planning; machining.
Investigations on the Machining Characteristics of Ti-6Al-4V Alloy during High Speed End Milling Process
by Samsudeensadham S, V. Krishnaraj, Thilak R, Prasath V
Abstract: In recent years titanium alloys have gained prominence in aircraft component manufacturing because of their higher specific strength and aversion to oxidation. High speed machining of high hardness materials like titanium alloys under dry environmental conditions takes through a lot of challenges in maintaining a better surface integrity. This machining study emphasises the analysis of surface integrity concerning high speed machining conditions during end milling of Ti-6Al-4V alloy in dry cutting environments. The experiments were carried out under the cutting speeds of 100 to 140 m/min. The milling forces were measured in the feed, tangential and axial directions. Virtual measurement of temperature was performed through a thermal camera. Experimental tests reveal that machining parameters such as feed and speed have a higher influence on milling force and surface roughness when compared with the axial depth of cut; simultaneously cutting speed has a higher influence on the temperature induced micro harness.
Keywords: high speed machining; Ti-6Al-4V alloy; temperature; milling forces; surface integrity.
Virtual reality platform for design and evaluation of human-robot collaboration in assembly manufacturing
by Patrik Gustavsson, Anna Syberfeldt, Magnus Holm
Abstract: This paper presents
Keywords: human-robot collaboration; HRC; human-robot interaction; HRI; virtual reality; augmented reality; speech recognition.
Integration of Augmented Reality Smart Glasses as Assembly Support: A Framework Implementation in a Quick Evaluation Tool
by Oscar Danielsson, Anna Syberfeldt, Magnus Holm, Peter Thorvald
Abstract: Augmented reality smart glasses (ARSG) have been successfully used as operator support in production. However, their use is not yet widespread, likely in part due to a lack of knowledge about how to integrate ARSG into production. This lack of knowledge can also make it hard to estimate whether this is a worthwhile investment. Our solution is to provide an online evaluation tool to help production planners estimate the likelihood that ARSG will be worth the investment cost in specific production cases. Based on a strawman design, multiple design iterations were followed by a pilot test performed by participants from different manufacturing companies involved in planning production for operators. A Likert scale survey was used to evaluate the tool. The results show a slightly positive evaluation of the tool with suggestions for improvement, including widening the scope and granularity of the tool. Future works include further iterations and case studies.
Keywords: augmented reality; AR; augmented reality smart glasses; ARSG; assembly operator; framework; evaluation tool; focus groups.
Optimization of EDMed fly ash and Rice husk ash reinforced hybrid Al-based composite using improved COPRAS and Entropy method
by Mohan Kumar Pradhan
Abstract: Rice husk ash (RHA) and fly ash (FA) pose a hazard to human health environment and are available abundantly across the globe. Attempts are being made to use such waste materials to create aluminum-based composite materials that can be used in a spectrum of uses. The Al6061/RHA/FA hybrid composite was prepared with 2.5 wt.% of each RHA and FA particle using a stair casting technique. This paper discusses mechanical characteristics like tensile strength, hardness, percentage elongation, and surface morphology were investigated using SEM. Besides, machinability investigations have been carried out using electric discharge machining, targeting the productivity of the component, quality, and accuracy. Taguchis L9 array was used to investigate the impact of parameters like pulse current, duty-cycle, pulse ontime, and gap voltage on output parameters MRR, tool eroded, and radial overcut. Enhancements in tensile strength and harshness have been observed by the reinforcement of FA and RHA particles.
Keywords: die-sinking electro discharge machining; EDM; metal matrix composite; MMC; material removal rate; MRR; aluminium matrix composites; AMC.