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Use of the production systems modelling and simulation tools allows integrating both technical and organisational production preparation areas. The higher integration level the better utilisation of enterprise resources is. In the paper a comparison analysis of simulations results got for the model of a real production line is performed. The main motivation of the paper was to compare simulation results obtained in the two simulation tools it is FlexSim and Tecnomatix Plant Simulation in order to state if the simulation quality depends on the choice the simulation tool.

The paper presents the most important issues related to the scheduling of production orders in real manufacturing systems. In the elaborated method an and/or type graph of operations planning sequence of a production order is proposed for modelling the production system load. In a single structure the graph takes into account alternative routes of a production order realisation and the precedence constraints in presence of complex, hierarchical structures of processes. Two modelling ways of that process using the "operation on the edge" or "operation on the node" notation are also presented. In the developed method scheduling strategies, which have a major impact on the order of placing operations in the schedule and handling of production lots are also considered. By a state space graph representation of scheduling problem, using graph theory, it can be possible to analyze the structure and complexity of both the modelling problem and the graph search techniques.

Problems of design similarity identification and elements grouping play a key factor in the development of design standardization and the group technology methods. Design similarity identification methods are most often based on a comparison of codes ascribed to products design. Basically the code makes a quantitative product description including different product features. Whereas a qualitative description has constituted rather supplement of a quantitative description. The most important issue in a process of design similarity identification is a method of a product design description. This description is usually made with use of special codes composed of alphanumeric characters. The coding process allows reducing the number of data which are being processed during design similarity evaluation, but on the other hand in some cases it could cause information loss. Taking into account above there is still a need of working out of a new method of a product design description which will be able to reduce these negative features of coding techniques. In the paper a novel approach for a product design description is presented. It is proposed to apply a hybrid method for a design representation purpose. This method uses a combination of code chains for a product longitudinal cross-section representation and a spatial matrix for transvers sections. As a result of the conducted research a new method of a product design description was worked out. This method is especially suggested for application in automatic design feature recognition systems (AFR systems) in which a design feature database (DFD) is present.

This paper presents case study of data acquisition in non-automated discrete production system. The issue of acquisition of data from the production system in order to support company management is essential for the integration of business and manufacturing areas of the company. Properly organized data acquisition system, consisting of hardware, software and organizational solutions, should provide access to real-time data on production tasks, flow of materials and work in progress, usage and effectiveness of workers and equipment, and the quality of production. Availability of data depends on type of production system, more precisely on the level of automation of technological processes. The Manufacturing Information Acquisition System (MIAS) methodology has been used in order to support design of the data acquisition system for the company producing large tanks, in which there is no automated equipment and most of production operations are realised manually. The algorithm of acquiring data from workers, organisational solutions and data processing in developed “Mistrz” IT system has been described, as well as problems with MIAS encountered during system operation in early stages of introduction.

The existing manufacturing technology of small mechanisms elements (gears, gear racks, displacers, bushings, precise mechanical parts, implants) is based on standard material removal techniques (turning, milling etc.). The problem is a variety of a polyamide materials chemical composition. Each additive has a significant influence to the material machinability in technological process. In a result it changes also resistance for melting of material in heat influence area. The method is based on automatically adaptation of parameters with author GRIP NC software and repeatable check of outer layer surface quality in various conditions and cutting strategies. Siemens NX Manufacturing module was used as a tool for operation simulation, parameters correction and G-code post processing tool. Fast G-code Generations gives possibility not only of parameters correction (that can be easily made in G-code itself) but also to optimize trajectory. Iterative comparison of surface roughness and chip flow monitoring were the main criteria that decided of cutting speed modification. On the output of the proposed method the proper cutting parameters table was prepared as well as a set of manufacturing recommendations. The case study is oriented to three polyamide modified materials: ERTHALON 6 PLA PA 6G, ERTALON LFX PA 6G (oil additive) NYLATRON GSM IPA 6 (MoS2 additive). Each material has a different set of fitted cutting parameters. Achieved results could be the guidance and provide proper outer surface roughness for (rough and finish) cutting operations like: axial and radial turning, threading and cutting.

Nowadays, companies have to react dynamically to changes in the demand of a products. Therefore, the production processes should be properly planned. The problem arises when there are several options, but it is not known which version to choose. By using the KbRS tool, sample schedules for a certain production processes were shown. In addition, the program is not only focused on the achieved maximum process times, but also on the module related to the costs. Thanks to this solution, the decision-maker obtains information not only about times, but also costs. Of course, there are also specific constraints, which make a set of solutions. At this point, depending on the situation examined, which decision making people determines, which solution to choose. It can be a time-related version or a cost-related version. This is important because, manufacturers receive a signal from the market that informs about the need of a personalized products. This needs are characteristic of the so-called fourth industrial revolution, in which customers are looking for a personalized products. But also this revolution is connected with the integration: machines, people and computer systems. And next the price of personalized products are close to the price obtained in mass production. Therefore, apart from integration and security, there is need to have tools that will help planning production processes in dynamic changing needs.

The paper presents algorithms of control parameters selection of the Fused Deposition Modelling (FDM) technology in case of an open printing solutions environment and 3DGence ONE printer. The following parameters were distinguished: model mesh density, material flow speed, cooling performance, retraction and printing speeds. These parameters are independent in principle printing system, but in fact to a certain degree that results from the selected printing equipment features. This is the first step for automation of the 3D printing process in FDM technology.

This paper presents results of tensile tests carried out for specimens made of the selected group of the filament materials. As a manufacturing technology FDM 3D printing method was chosen. The selected group of the filament materials involved the group of wood, PLA, ABS, PET, PMMA and ASA. Herein, it should be noticed, that technical data sheets that are delivered by filament materials producers include data that are valid for only one specific printing direction. This printing direction is deliberately selected, in such way that ensures the best material characteristics. Therefore, received during the research results allow to make comparison between a catalogue data and data obtained in the printing process. It aids both mechanical designer and product manufacturer at the stage of the printed product mechanical properties shaping.

Feature Recognition (FR) technique is a technique for identifying and extracting design features from a geometric CAD model in order to obtain manufacturing and analysis information about a product.

In the paper a job shop and flow shop scheduling problems with availability time constraint for maintenance are considered. Unavailability time due to maintenance is estimated basing on information about predicted Mean Time To Failure/To First Failure and Mean Time of Repair of a machine. Maintenance actions are introduced into a schedule to keep the machine available in a good operation condition. The efficiency of predictive schedules (PS) is evaluated using criteria: makespan, flow time, total tardiness, idle time. The efficiency of reactive schedules (RSs) is evaluated using criteria: solution and quality robustness. For basic schedule generation Multi Objective Immune Algorithm is applied. For predictive scheduling Minimal Impact of Disturbed Operation on the Schedule is applied. After doing computer simulations for the job shop scheduling problem following question arises: do dominated Pareto optimal basic schedules achieve better PSs? Although a single Pareto-optimal solution is achieved on Pareto-optimal frontier three different schedules have the same quality in the flow shop scheduling problem. The question is: which schedule is the most robust solution?

Real-time information feed describing the state of production system is the key to successful management of any company, because up-to-date information is necessary basis for decision making in company operating on globalised market. Data describing the state of the production system should be collected in the manufacturing system, pre-processed, interpreted, filtered, archived and finally, either used in IT systems supporting company management (MES, ERP), or directly presented to crew and managers responsible for specific areas of interest. Possibility of data acquisition in companies strongly depends on specific of branch of industry, technological processes automation level, number of operations performed manually, type of production, etc. Acquisition of data on state of the production system should be carried-on automatically, without involvement of workers. This paper presents overall description of issues of data acquisition in company, proposed Manufacturing Information Acquisition System (MIAS) and the case study of data acquisition in company leading continuous, automated production processes Central Wastewater Treatment Plant (WWTP) in Gliwice, Poland.

The proposed idea of the integration methodology is based on the two basic pillars it is the modified functional model of the manufacturing process plan and a product intermediate states representation. The product state in certain moment of the manufacturing process can be identified by a set of states which describe the current status of the manufacturing process advance for particular manufacturing features. On the other hand from a manufacturing process nature results that during its course a product can be at one of the following states after rough, medium and finishing manufacturing treatment. Information about product states makes the full integration between CAPP and CAP systems possible. The proposed methodology allows reacting to unexpected production process disturbances. In this case the CAP system in cooperation with manufacturing execution system MES, which collects production data just from PLCs controllers, communicates with CAPP system in the feedback loop and sends a set of the product intermediate states. Base on this description the CAPP system redesign a manufacturing process plan taking into account the current product state. In the paper the modified functional model of the technological process plan and the method of product intermediate states are presented. Moreover the proposal of the functional schema of the integrated CAD/CAPP/CAP environment is shown.

In the paper, a production model with maintenance is presented. Successive failure-free times of a bottleneck are supposed to have predefined distributions and are followed by distributed times of repair. Having values of parameters: Mean Time To Failure and Mean Time of Repair, a predictive schedule is generated. To assess wastes due to unplanned events of the bottleneck, such as unplanned downtime the Overall Equipment Effectiveness indicator is applied. To assess failure rate of the bottleneck the Parts Per Million Opportunities indicator is applied. Prediction capability, detection capability of a failure and effects of the failure occurrence are evaluated and registered in the Exploitation Failure Mode and Effects Analysis form. The objective of the presented predictive scheduling model is to achieve: zero machines failures, zero defects, zero accidents at work.

An operation of a single-machine manufacturing system is modeled by an unreliable finite-buffer-type queuing system with Poisson arrivals, in which service times, failure-free times and times of repairs are totally independent and exponentially distributed random variables. Applying the idea of embedded Markov chain and the formula of total probability a system of integral equations for the transient conditional queue-size distributions of jobs present in the system at fixed time t is built. The solution of the corresponding system written for Laplace transforms is obtained in a compact form using the potential technique.

The need of integration of all engineering activities starting from a designing stage finishing on manufacturing implies the necessity of application of a new software solution. Among them CAPP systems seem to be the best and the most promising integration tool. There are the two basic methods of the computer aided process planning it is the variant and generative methods. These CAPP modelling methods are based on the different principles. The variant method is based, in general, on the ideas of the design similarity and group technology whilst the generative one mainly on the basis of utilization of the manufacturing knowledge store and the automatic process synthesis. It is a well-known fact that the variant process planning approach is based on the hypothesis that similar parts would have similar process plans. In a CAPP variant process planning system it is necessary to look for similarities between parts. Process plans formerly prepared and stored in the CAPP system manufacturing database are used for planning of new manufacturing processes for new parts similar to those recorded in system database. In the variant system working out of the classification schema and similarity measures is essential. In this paper an attempt to application of chain codes for a design similarity evaluation is presented. The proposed procedure is based on application of the chain codes for description of the parts selected longitudinal cross sections. The proposed chain code structure is created in similar way to this used for the Freeman code formation but unlike classic Freeman chain code the parts cross section is discretized in more than the 8 cardinal directions. The characteristic feature of the proposed profile coding method is the approach for the code starting point selection. In each case the part design chain code is created starting from the a priori selected upper left corner of a product. The idea of products similarity evaluation bases on the parts profile codes and application of the minimum edit distance definitions. In the paper the Levenshtein and Hamming distance for code chains similarity comparison are proposed At the current stage of research this method is used for similarity evaluation of rotational symmetric parts. The choice of the minimum edit distance measure in the proposed solution depends on product pins number.

Rescheduling, as a process of updating the production schedule is a very important element of production planning and control. The occurrence of events that outdate existing schedule is a typical situation in real manufacturing systems. Correct reaction to them allows maintaining the continuity of production and the value of evaluation indicators at the satisfactory level. The paper presents the general rescheduling procedure including activities taken from the occurrence of a disturbance up to introduction of the revised schedule. The procedure includes following steps: registering and identification of the event parameters, decision-making steps about the need and time for schedule correction, steps of changing the scheduling model, selection of rescheduling method, selection of a set of operations to rescheduling and also steps of the creation, selection, and implementation of the new schedule .

In the paper a production model with failures is presented where successive failure-free times are supposed to have normal distributions and are followed by normally distributed times of repairs. Unknown parameters of distributions are estimated using e.g. empirical moments approach. Predictions of unknown parameters are done using classical regression method. Having Mean Time To First Failure, and Mean Time of Repair a disturbance robust predictive schedule is generated using rule: Minimal Impact of Disturbed Operation on the Schedule. If a machine's failure-free time is not successfully predicted reactive schedule is generated using criterion: Minimal Impact of Rescheduled Operation on the Schedule.

In the paper the role of the decision maker in the process of production scheduling is discussed. A general procedure specifying the activities carried out within the framework of particular steps of scheduling is shown. The scope of the interactions of the decision maker in the scheduling process under conditions of real time system is commented. The purpose of this work is to present a range of knowledge and information which should have a decision maker and also the advantages and disadvantages of each method of participation. The work in this area is one of the most important steps when designing a new, dedicated scheduling system as well as during the analysis, selection and adaptation of an external one.

In the paper a survey of predictive and reactive scheduling methods is done in order to evaluate how ability of prediction of reliability characteristics influence over robustness criteria. Survey analysis is done for two job shop scheduling problems: 5x8 and 5x10. The paper answers the question: what method generates robust schedules in case of a failure of a bottleneck occurrence before or after maintenance actions? The Hybrid - Multi Objective Immune Algorithm (H-MOIA) is aided with heuristics: Minimal Impact of Disturbed Operation on the Schedule (MIDOS) for predictive scheduling and Minimal Impact of Rescheduled Operation on the Schedule (MIROS) for reactive scheduling. Sensitivity analysis is done for predictive scheduling methods 1) H-MOIA +MIDOS, 2) algorithm based on priority rules: the Least Flexible Job First (LFJ) and the Longest Processing Time (LPT) and 3) the Average Slack Method. Reactive schedules are generated for various scenarios of the bottleneck occurrence in order to evaluate the efficiency of predictive scheduling methods. Reactive schedules are generated using 1) H-MOIA+MIROS, 2) Right Shifting, 3) rescheduling disturbed operations to parallel machines first available. Efficiency of predictive schedules is evaluated using criteria: makespan, total tardiness, flow time, idle time. Efficiency of reactive schedules is evaluated using: solution robustness criterion and quality robustness criterion.

A queueing system of the M/M/1/N type with cyclic failure-free and repair times is used as a model of a single-machine manufacturing line. Jobs arrive according to a Poisson process and are being served with exponentially distributed processing time. Successive working (failure-free) and repair times have exponential distributions, too. Basing on a system of integral equations for double transforms of conditional probability distributions of the number of jobs completely processed before the fixed time (departure process), comprehensive numerical analysis of the impact of system parameters on the mean number of departures before the fixed epoch T>0 is carried out.

Element geometry can be restored with basic measurement techniques. However if the element geometry is too complex (free form surfaces), it is not possible to take all measurements in that way. Example presented in the paper is a drop forged element (car suspension link). In situation when spare element is out of reach (product withdraw from market, producer technological process tooling redesign), the element can be reproduced (singularly or in series, what depends on producer). Reconstructed element is slightly different from a master element (impossible existence of reliably identically designed and manufactured parts), because of measurement uncertainty. Another problem is that original element is usually worn out or during disassembly process can be damaged, so it has different geometry,(when worn out is not fitting to tolerances) than newly manufactured one. The practical approach for reverse engineering is based on: measurement uncertainty extrapolation, 3D part scanning, transformation of point cloud to solid model, composition examination of an alloy. The method is a complex solution that brings: geometrical description and material assignment and heat treatment. Important part of the method is typical measurement techniques. In cases when tolerances have to be preserved, additional tolerance assignment is needed according to linkage between redesigned part of element and parts of other elements in assembly. The insurance of measurement was checked according to typical tolerance of the drop forged element. The retrieved 3D model was compared with virtual mass to real master element mass. The technological tooling reconstructed prototype and element reconstructed prototype have been made. Finally the alloy material is assigned according to measurement result analysis (electron spectroscopy EDS). Proposed example shows many important clues that can be used in order to provide properly redesigned element.

The paper presents a solution useful for production scheduling in the context of the constraints arising from the complexity of the structures of realized processes and possibilities of use variants of their implementation. The proposed method uses both activity on arc and activity on node types of graph for describing multivariant processes. Representation of complex (composed) structures the AND-OR graphs are used that combines both conjunction and disjunction relations between nodes.

The modeling phase of the computer system development is one of the most important elements affecting the final success of the created software. Structures developed at this stage are the basis for the design and implementation of computer program code. The paper presents the general model of static structures (main classes and their relationships) of production scheduling system supporting discrete and multiassortment production. In the description of the object-oriented model a graphical systems and specifications modeling language notation UML was used.

Having in mind the need of the computer adding of the technical production preparation functions the elaboration of models of the design and knowledge representation is essential. In order to prepare these models the object paradigm in the meaning of object oriented techniques and the UML language would be applied. Thanks to this solution the coherent representation of the design and manufacturing knowledge in the framework of a new created CAPP is possible to achieve. The main purpose of the presented work is to show and discuss original models of a design and manufacturing knowledge representations. In the proposed solution the product design is represented by means of the hierarchical class structure in which a particular class is responsible for representing a characteristic type of the model feature. The manufacturing knowledge similarly to knowledge representation is also represented by means of the hierarchical class structure. Each class in the manufacturing knowledge model stores a certain amount of manufacturing knowledge. This model allow representing both procedural and declarative knowledge. The declarative character of the model results from storing of manufacturing process planning rules whilst procedural one from recording of manufacturing instrumentation, cutting parameters etc. selection procedures. Having these models done it is possible to undertake a research on connections between a design and manufacturing knowledge representations.

Process planning is one of the most important links in planning of the manufacturing system functioning, it coordinates and integrates processes planners, designers and economists intentions. The main goal to reach during the process planning phase is to determine the process plan structure it is manufacturing operations and cuts which have to be applied in order to transform given semifinished product into a product with the strict determined design and properties. Simultaneously process planers strive for working out such a process plan which satisfies criteria of the lowest manufacturing cost and labour consumption taking into account current accessibility of manufacturing resources. Process planning is still one of the most difficult, complex and time consuming process planner activities. Traditionally the process plan is designed with so-called manual method. During process planning with this method a process planner is forced to analyse the sequence of manufacturing cuts and operations in the process plan structure and also to analyse alternative processes taking into consideration achieving as low as possible unit manufacturing cost. In this case the process plan quality in principle depends exclusively on process planner knowledge and skills. Taking into account above the methods of process planning functions automation are searched. This goal can be reached by application of computer tools. Computer methods of process planning went through the long evolution process and their development is characterized by the following features: decreasing of process planner participation in the planning of the base structure of process plan, broad application of technological databases, broad application of technological knowledge bases, and possibilities of cooperation with commercial CAD/CAM/CAE systems [1,. In this paper the detailed information on methods of computer aided process planning are given. The variant, semi generative and generative methods are discussed. The main merits and drawbacks for each method are shown.

Currently industrial needs exceed traditional design approach solutions. To satisfy that need designer have to deal with mutually exclusive restrictions. The solution to this problemis to maintain these restrictions with proper methodthat guarantees right result. The concrete casting matrixes are not only transits beauty and art but they have also important technical sense in final product. The master model represents the final product a concrete sidewalk brick which have specified form of the top surface. This special structure of the top surface helps drain water off the brick in order to maintain proper griping properties of it after it rains. As soon as the master model wasscannedit was necessary to change outer border line of 3D model because themaster model appeared to be a little bit bigger than the original one. Finally the 3D model it is the outer border line and its geometry were modified in order to keep the original model functionality. All modifications were done with application of reverse engineering and CAD/CAM software.

In this paper a solution of soft real time scheduling in manufacturing systems is presented. The basic requirements of scheduling as a real time system are discussed. The proposed rescheduling method uses predictive-reactive strategy and multi thread searching approach with rule-based heuristics, meta-heuristics and random modules.

A single-channel queueing model with finite buffer capacity, Poisson arrival stream and generally distributed processing times is considered. After each busy period the service station is being switched off but this operation requires a randomly distributed closedown time. Similarly, after the idle time, the first service in a new busy period is preceded by a random setup time, during which the processing is still suspended and the server achieves full readiness for the service process. A system of integral equations for transient conditional queueing delay distribution is derived, by using the idea of embedded Markov chain and the formula of total probability. The solution of the corresponding system written for Laplace transforms is obtained via the linear algebraic technique. Numerical examples are attached as well.

The paper focuses on the scheduling problem of minimizing flow time of production orders in job shop class systems. The proposed method supports both forward and backward scheduling and use additional backward pass for calculating the latest possible release date of a given production order. Depending on the adopted strategy, two or three stages are implemented in which the new due date and new release date is searched successively for each production order. Application of this approach causes that the scheduling of any order can be realized according to one of five ways. Four decision steps associated with the choice of the right method of order scheduling were distinguished. Examples illustrating the application of the proposed approach for the case of the forward and backward base strategy were also presented.

Aerosol products combine convenience of use, various possible applications and high performance. Thanks to these features, a steady increase in their sales is observed on the global market. Yearly, over 15 billions units are globally produced and among this more than 5,5 billions are made in Europe [1, 2]. An integral part of the aerosol product is its packaging. As the size of the aerosol market opens the gate for innovations, packaging components' manufacturers try to develop packaging in both construction, material, technological and marketing directions, to get the bigger share of worldwide aerosol market. The article will review the solutions which are currently used as well as the innovations in the context of aerosol packaging. It will also demonstrate the need for further development within this segment of industry.

The necessary condition that must be performed in order to ensure full functional integration of the computer aiding systems of technical and organizational production preparation is utilisation of the coherent product model. Utilisation of feature method for representations of the construction and the technological process elements is a key factor for integration of design and technological process planning—CAD/CAPP integration model. The availability of alternative process plans plays the main role in the CAPP/PPC system integration. The main advantage of the accessibility of alternative process plans for product is that we may fast react on a disturbance in the course of the manufacturing process by help of the reactions knowledgebase—one of the module of proposed PPC system. This paper describes a methodology for integration CAD/CAPP/PPC systems in detail.

This paper presents a method of representation of the knowledge about the body construction and technology in an expert system that aids the process of designing the machining technology of bodies. The proposed method of object knowledge representation allows recording the technological knowledge acquired from experts. An example of knowledge notation using the Object Pascal language is presented.

Rapid Prototyping technologies, especially 3D printing are becoming increasingly popular due to their usability and the constant decrease in price of printing equipment and materials. The article focuses on the study of selected mechanical strength properties of 3D-printed elements, which are not very important if the element is only a model for further manufacturing techniques, but which are important when 3D-printed elements will be a part of a functioning device, e.g. a part of unique scientific equipment. The research was carried out on a set of standardised samples, printed with low-cost standard materials (ABS), using a cheap 3D printer. The influence of parameters (such as the type of infill pattern, infill density, shell thickness, printing temperature, the type of material) on selected mechanical properties of the samples, were tested. The obtained results allows making conscious decisions on the printing of elements to be durable enough, either on a non-professional printer, or when to ordered by a professional manufacturer.

This paper presents a novel approach to a problem of the design feature library elaboration. As a tool of the design feature library development CNC machining cycles were proposed. Because of the great number of commercially available CNC machine controllers, with different CNC machining cycles definitions, it was necessary to make a decision about a research methodological framework, it is the selected CNC machine controller. Taking into account the criterion of popularity as the research framework the selected group of Sinumerik CNC machine controllers was chosen. Presented in the paper idea of the feature library development is based on an assumption saying that it is possible to find a relationship between a particular CNC machining cycle and the simple design feature or even compound design features. Identified, thanks to this assumption, set of the design features could be the base for elaboration of the design feature library. This solution, it is the feature library next gave opportunity for elaboration of the feature based design modelling module (FBDMM) working in the SIEMENS NX system environment. Hence, the FBDMM module can support both a designer and CNC machine programmer which is possible due to received in the module modelling paradigm. In FBDMM module the removal feature based modelling technique is received.

The paper presents application of ant colony optimisation algorithm for scheduling multi-resources operations in flexible job shop type of production systems. Operations that require the participation of two or more resources are common in industrial practice, when planning are subject not only machines, but also other additional resources (personnel, tools, etc.). Resource requirements of operation are indicated indirectly by resource groups. The most important parameters of the resource model and resource groups are also described. A basic assumptions for ant colony algorithm used for scheduling in the considered model with multiresources requirements of operations is discussed. The main result of the research is the schema of metaheuristic that enables searching best-score solutions in manufacturing systems satisfying presented constraints.

One of the most important characteristic of each queueing model is time to buffer overflow. In the paper the distribution of that time in a single-channel manufacturing system, modelled by a Markovian finite-buffer queue with machine breakdowns, is studied. By using the analytical approach based on the idea of embedded Markov chain, total probability law and linear algebra, the formula for Laplace transform of the time to buffer overflow conditional distribution is found. Numerical illustration is presented.