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This article presents the methodology and process of the modeling, designing, and testing of a research station enabling the identification, tuning, and verification of Digital Twin (DT) in control systems in power hydraulics. The concept of the station is presented, the main part of which is a subsystem forcing a dynamic, variable load using a hydraulic actuator controlled by a proportional valve, together with data acquisition and processing systems and software. The load application subsystem can subject the tested power hydraulic system, usually consisting of an actuator with its own control system, to controlled dynamic loads, which allows for the determination of its characteristics and tuning of the DT. This article describes the electro-hydraulic elements used to adjust the position of the actuators and the designed hydraulic and electrical diagrams of the station. The process of identifying, modeling, and selecting a controller for a subsystem simulating an external load is presented. The test station is built and tested. The identification, modeling, and tuning of DTs, for example, actuators and controllers, are described. A satisfactory convergence of the simulation and modeling results with the operation of the real system is achieved, which allows the obtaining of a reliable DT for actuator control systems operating under variable load. [ABSTRACT FROM AUTHOR]

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.

The paper presents issues related to data acquisition and communication between the manufacturing system and the business area of a company, understood as the transmission of real-time information about the status of the production system (the state of equipment, production tasks, workers, the flow of materials, work in progress and products), and, production orders, which is the basis of the Industry 4.0 concept. Data can be acquired from various sensors, PLCs and automatic identification systems, through interfaces (e.g. IO-Link, OPC, MTConnect), providing translation of data between different producer’s equipment and software. The article presents assumptions, concept, interfaces, as well as hardware and software equipment of the Integrated Manufacturing Systems Laboratory, allowing research and teaching of integration of production and business areas. Laboratory workstations equipped with PLCs (3 different producers), sensors (e.g. distance, proximity, colour, position), actuators, HMI panels, hardware interfaces, RFID readers, barcode readers and vision systems, interfacing through OPC, IO-Link or Profinet with SCADA and other IT systems have been presented. An example of systems integration has also been presented.

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.

Industrial robots are widely used in mass production, successfully replacing the workers during repetitive tasks. The lack of direct human participation in the production process involves the necessity of programming of the machines, which is mostly the time-consuming process. Most of the operations are well described in the process documentation, but some actions require the use of complicated paths, like for example welding, laser or water cutting, edge grinding, application of liquid sealants or films of paint etc. All of the mentioned activities need the precise movements of robot’s effector and this is - in many cases - connected with the necessity of entering of many points that approximate the path. One of the ways to solve this problem is the possibility of generating the complex path automatically, using the information from the technical documentation. This paper presents such approach that uses the CAD drawings as a data source. The available literature presents this problem mainly in the aspects of large software applications, but this paper was focused on presenting the problems of the proper analysis of the drawing and how to process the data to the form that can be used during robot programming.

The article presents tests on the possibility of using ultrasonic transducers for accurate distance measurement in hard coal mines. In order to check the impact of selected disturbing factors on the measurement results, test stands were built, and then a full cycle of measurements with the use of different transducers (AR30 and AR41), which were selected and pre-tested in previous research projects, was realized. The impact of such disturbing factors as airborne dust (coal, stone, lime and mixed dust), changes in temperature and humidity on the propagation of ultrasonic waves, amplitude and measurement accuracy was investigated. The tests were preceded by theoretical analysis. It was found that the transducers selected for the tests had a sufficient accuracy and range, so they can be used in the devices planned to be designed, allowing for the determining of the location of a roadheader in hard coal mine roadways, taking into account technical and legal restrictions. It was also specified which disturbing factors should be compensated and what methods and parameters of this compensation should be used. [ABSTRACT FROM AUTHOR]