Advanced Materials Research Vol. 1036

Abstract: The most important element of the production process is the optimization of the conducted operations. It is particularly important for the lean production process. In the paper is presented the analysis of the optimization approach using the CAE systems, the multi-agents systems (MAS) and the distributed robotics (DR) systems. Using the CAE techniques it is possible to elaborate the virtual environment in which the manufacturing cell is designed. The interaction between the virtual model and the process rule base allow improving the design of the existing standard machining technology. The MAS approach let to create the structure of the manufacturing process, taking into account both the machining stands and transport units according to the elaborate technological process. Finally the utilization of the DR approach for the optimization of transport operations including the heuristic algorithms. Moreover in the paper are presented the results of the investigations of analyzed problem on the base of complex production line for the cylindrical elements. The simulations and other analysis have been conducted in advanced computer systems. Also the basic relation between mentioned systems are discussed.

Abstract: The paper presents the task scheduling issue, which main aim is to establish a proper sequence of tasks, that would maximize the utilization of companys production capacity. According to the literature sources, the presented sequencing problem, denoted as CSP (Car Sequencing Problem) belongs to the NP-hard class, as has been proven by simple reduction from Hamiltonians Path problem. Optimal method of solution has not yet been found, only approximate solutions have been offered, especially from the range of evolutionary algorithms. Regardless of specific production system, while considering reception of new tasks into the system, current review of the state of the system is required in order to decide whether and when a new order can be accepted for execution. In this paper, the problem of task scheduling is limited to the specific existing mixed-model production system. The main goal is to determine the effective method of creation of task sequence. Through the use of computational algorithms, and automatic analysis of the resulting sequence, rates of production are able to be checked in a real time, and so improvements can be proposed and implemented.

Abstract: : In this work there were developed fundamentals in parameter definition of products routing in flow-spatial technological systems which have branching flows of products. In work there have been established initial conditions for definition of parameters of products routing.In work there were considered peculiarities of operation of flow-spatial technological systems with branching flows of products. There were developed basics of definition of parameters of products routing on the basis of multidimensional algebra of groups.

Abstract: 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

Abstract: This paper aims to analyze the classical transport system using only two processing centers, maintenance can ensure, without negatively impacting the transportation system optimization. To achieve transport system simulation packages have been used to simulate Petri and implementation specialist and preparing conclusion is made based on data specialist. The model is intended to be a source of help in the activities of companies seeking to optimize the transport system and not be disrupted by achieving maintenance. Benefits are those prototypes and analyze the whole system after the implementation of tracking and being able to control the entire system, leading to the prevention and elimination of queues later appearance possible accidents. Studying this system model can deduce new information without the high costs.

Abstract: 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.

Abstract: The main achievements presented in this paper are developed method orientated on computer aiding and computer program method, both used in designing process of the new technical features. Analyzed methods develop algorithmisation of selection features and support integration with the process of the preparation of the production. Further analyses will be carried on in order to specify the theory of the technological similarity in the new forms of computer aiding (relational databases). The represented programs were being developed on the practical examples of creating the module systems of hydraulic cylinders used in mining, slag cars used in metallurgy and gears series of types. Programs and data bases presented in the paper are basis of selection of the technological features in the process series of types of the technology creating. All of these applications support the intensive development of the types of technical features and affect on their competitive on the ready market.

Abstract: 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.

Abstract: ERP systems help organizations to monitor and report on environmental factors, both in the area of individual plants or entire companies. Regular monitoring and analyzing indicators of impact of the company on the environmental enable organizations to determine the effects of the implemented environmental programs. Article concerns the monitoring and reporting of environmental impact in relation to the use of raw materials and semi-finished products in manufacturing processes.

Abstract: 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.