APPLICATION POSSIBILITIES OF DYNAMIC VALUE STREAM MAPPING IN PRODUCTION LOGISTICS

An increase in the number of product types required by customers results in an increase in the complexity of logistics systems. This finding is particularly characteristic of production logistics systems, where the use of flexible production systems is becoming increasingly important. One of the defining tools for the development of these processes is the value process mapping method, a static version of which suitable for the simultaneous examination of a product family has become widespread in corporate practice. The paper presents the method of dynamic value stream mapping, which is also suitable for the examination of complex logistics systems, exploring its steps and the possibilities of its application in production logistics. An example prepared using the VSM module of the Plant Simulation framework is also presented to illustrate the application of the method.

Automation technology as a key component of the Industry 4.0 production development path

Since 2011, the Industry 4.0 initiative is a key research and development direction towards flexible production systems in Germany. The objective of the initiative is to deal with the challenge of an increased production complexity caused by various factors such as increasing global competition between companies, product variety, and individualization to meet customer needs. For this, Industry 4.0 envisions an overarching connection of information technologies with the production process, enabling smart manufacturing. Bringing current production systems to this objective will be a long transformation process, which requires a coherent migration path. The aim of this paper is to represent an exemplary production development way towards Industry 4.0 using eminent formalization approaches and standardized automation technologies.

ESTIMATION OF THE EFFICIENCY OF FLEXIBLE PRODUCTION SYSTEMS AND ROBOTIC COMPLEXES USING SIMULATION

The article presents a methodology for forecasting and analyzing the effectiveness of the use of flexible production systems and robotic systems. Simulation modeling and queuing theory are used as analysis tools. The production program for the release of products, which has a certain nomenclature and production volumes, is represented by a flow of applications. The production process is modeled over time and various technological situations are predicted. The computational experiment is conducted on the basis of the developed program using the object-oriented programming paradigm in Python. A probabilistic model of the dependence of the quality indicators of the line on the production program for manufacturing parts is implemented. Variants of production programs are presented in the form of combinations of dispersion fields of stages of the life cycle: frequency of receipt of parts and pro-cessing time on machine tools. The frequency of receipt of workpieces on the processing line is ap-proximated by an exponential law; the time of mechanical processing on machines is approximated by the law of normal distribution. A number of series of computational experiments have been carried out and their results have been analyzed, which characterize the stability of the line operation through the values of quality indicators: changeable loading of machine tools, loading of a parts accumulator, the probability of its overflow. The main regularities are revealed that provide high indicators of the shift loading of equipment, as well as the factors leading to their decrease.

Improving Energy Efficiency of Flexible Pneumatic Systems

During pneumatic control system design, the critical value for choosing the appropriate pneumatic actuator is the weight of the workpiece. In the case of flexible production systems, which are the core part of the Industry 4.0 (I4.0) concept, the weight of the workpieces is often variable, since the crucial feature of this kind of production is its ability to deal with variable parts. Therefore, in order to deal with the variable weight of parts, a pneumatic actuator is chosen according to the heaviest part. However, according to another I4.0 principle, energy efficient operation of machines, the previous criteria for choosing a pneumatic actuator is energy efficient only when handling the heaviest part. In all other cases, operation of the pneumatic actuator is suboptimal in terms of energy efficiency. Aiming to solve this problem, this paper considers the possibility of using a new pressure regulator instead of traditional manually adjusted pressure regulators. This regulator provides operating pressure modification in real-time in accordance with the weight of the workpieces. In this way, the optimal compressed air consumption is ensured for each workpiece. Implementation of this device has yielded significant energy savings; however, the value is variable and depends on working task characteristics.

Applied Simulation Modelling and Evolutionary Computation Methods in Industry 4.0 CPS Architecture

Industry 4.0 has recently opened a number of new research questions relating to the production scheduling of flexible production systems. The high complexity of flexible production systems` scheduling is reflected in the multi-objective nature of optimisation problems, which cannot be solved satisfactorily with conventional techniques. Researchers are developing various optimisation techniques based on the use of advanced evolutionary computation methods and simulation modelling, but it is difficult to transmit the proposed solutions to the real world of Industry 4.0. The chapter present new method of evolutionary computation and simulation modelling for the purpose of comprehensive multi-objective optimisation of flexible production systems. In the research part, the chapter presents an applied example of the advanced optimisation methods used in order to provide timely and economically sustainable production systems in Industry 4.0. The research results prove the importance and justification of using the proposed CPS architecture ensuring economic and time optimised production systems.

PREVENTING PROCESS FATIGUE WHEN FINISHING A PART

Possibilities of preventing the appearance of fatigue cracks during finishing processing of a part by changing the elastic–mechanical characteristics of the workpiece due to the accumulation of fatigue defects preceding the appearance of a crack are considered. Modules of elasticity and shear are considered as characteristics to be controlled under the assumption that the material of the part is isotropic. To control these values, the equation of vibrations of the part is used, which is solved by the numerical method, and the values of E and G are selected, corresponding to the measured displacements of surface points that occur during a given movement of the processing tool. The movements are proposed to be measured remotely. The obtained sequences of estimates of the elasticity and shear moduli form two time series, according to which a long–range forecast is made, and the limiting values of the sequences are calculated with an unlimited increase in time. The fatigue criterion is the reduction of these values at the present or future points in time below a preset value. Depending on the degree of reduction, a decision can be made to reject the part or to correct the technological process with a change in the law of the machining tool motion. The proposed control method can be used in the construction of flexible production systems.