Mariusz Piotr Hetmańczyk

The Self-Excitation Phenomenon of Quasi Shielded Inductive Proximity Switches

Authors of this article had to build the Poka-Yoke [ unit for unusual geometry element, which require to use the inductive proximity switches with relatively small diameter and good sensing range. Industrial sensors suppliers putted on to the market new type of sensor named quasi flush or semi flush which fulfill the needs. An article shows the observed influence of the geometry of tested elements for the self-excitation phenomenon of quasi shielded inductive proximity switches. In consequence this phenomenon can cause in false quality control and passing the wrong elements through the Poka-Yoke unit.

Adaptation of the Expert System in Diagnosis of the Connection of the PLC User Interface System and A Field Level

Authors of the paper focused on the problem of devising a concept of computer-aided diagnosis system of a centralized PLC control coupled with the distributed drive systems operated by frequency converters via the ProfiBus industrial network. It is worth emphasizing that the presented concept is useful in all automated systems characterized by the PLC centralized control. The paper provides the description of one of the several modules of dedicated software developed by the authors [6].

Hardware and Software Integration of Mechatronic Systems for an Example Measurement Path for Temperature Sensors

This paper presents the method of designing a mechatronic system, as a result of an integration. As an example of the integration automation components, in one coherent measuring system, a measurement path for temperature sensors is proposed. A measuring path can be defined as a scale model, which reproduces thermal states of a temperature sensors system, used in real industrial applications. The system is extended by database application based on Access. Taking advantage of an iFIX special database block the temporary values of temperature are recorded in Access database with permanent period of time. The final analysis is performed in an Excel sheet.

The Reliability Model of AC-Asynchronous Drive Based on the Multilevel Prognosis System Supported by Matrices and Digraphs Methods

Author of this article presents an authorship reliability model of a AC-asynchronous drive written in accordance with assumptions of the multilevel prognosis system based on matrices and digraphs methods. Described model take advantage of knowledge gathered from specialists on the basis of their experience. It is worth to stress that parameters of the reliability model of the AC-drive meet the requirements of units utilized in case of distributed drives. Each change of its application range requires a modification of internal parameters, but the functional structure remains without any variations, because presented reliability model has been based on the functional structure. An intention of the author is focused on an elaboration of a collection of reliability models [ of distributed drives components, prepared in accordance with the multilevel system of prognosis based on matrices and digraphs methods. The model has been specified to the level of the independent subsystem. This approach allows the use of this model in the analysis of complex systems, consisting of separated drive subsystems, which meet the requirements of the method. Using multilevel prediction models should be possible in all applications of electric drives, regardless of purpose functions.

The Aid of a Mistake Proofing with the use of Mechatronic Systems According to the Poka-Yoke Methodology

An important aspect raised in the article is the practical application of rules dedicated to Poka-Yoke systems using real industrial automation components that enable detection of defective elements. The article includes also an optimization of the structure of constructed devices for an unambiguous determination of the Poka-Yoke criteria and a minimization of the possibility of random errors made by the employee (or intentionally deceives of sensor systems). Despite clear conditions of the method the authors observed a lack of publications related to the description of the implementation of equipment elaborated in accordance with the presented methodology in industrial applications. This article presents the authors Poka-Yoke system used for a detection of drawpieces made of steel (with welded nuts) which are components of systems of passenger cars.

Influence of the Controller Settings on the Behaviour of the Hydraulic Servo Drive

The article presents the influence of the position loop gain setting on the position error values of the hydraulic servo drive. Results of the experimental tests have also been compared with the analytically determined gain values. For the tests, servo cylinder has been loaded with the active force of 2500 N, pointed in the direction opposite to the direction of piston rod extension. The result of the experimental tests was the discovery that the accuracy and stability of the servo drive positioning depends not only on the value of Kv factor, but is also influenced by the direction of the active force loading the servo cylinder. In the tested hydraulic servo drive (hydraulic axis controller), the Compax3F controller by Parker Hannifin was used.

Simply-Integrated Method of Judgments of Expert Knowledge Collected in Databases for Objective Computer-Aided Engineering Systems

Prediction of the machinery or process malfunction states is one of the important and challenging task for knowledge engineers. Nowadays it is a common situation, that the reliable companies collect all kind of important knowledge and by the work of knowledge engineers remake it for well known know-how. The problem we would like to solve is touching the area of objective computer-aided engineering systems. The new proposal of the method for judgments of the expert rules collected in the databases which is arbitral in our opinion has been described in this article. New method based on aggregation process of subjective marks of reasoning rules from independent experts, which gives back an more objective parameters for faster computing of the reasoning process. Thanks to this the malfunctions can be reduced to minimum or much faster eliminate.

The Multilevel Prognosis System Based on Matrices and Digraphs Methods

The author of this article considers new approach based on operational reliability models, written in the form of matrices and digraphs methods. At a core of the method the author used the theory of systems and their decomposition consistent with the FMEA methodology [, that allows a simplification of the distribution of elements within the system into smaller parts having a greater susceptibility to the error analysis and forecasting of their states. The method mainly refers to decentralized systems, linked via reciprocal relationships (that can be applied to manufacturing work centres, transport lines, etc.), containing subsystems that use the control, power, noise and mass flows streams. Article includes also main assumptions of described method, realizability studies, application areas and significant restrictions.

The Prediction Oriented Analysis of Mechatronic Machine Structures in Terms of the Signal Stream Flow

The article describes an approach dedicated to a hybrid representation of mechatronic systems combining matrix and block notations. The main attention is focused on the identification of relationships between mechatronic machines in respect of functional reliability (analysed in the form of block and digraph notations) and rules that allow for the simplification of the reliability function in the systems of machines connected in parallel, series and complex arrangement. The author has adopted a functional representation based on system demonstration employing a binary function of reliability in which the equation is determined based on the method for setting minimum paths in the graph (structural representation of each subsystem). The introduced assumption allows reducing any structure to a serial connection of functional blocks. The author of the paper has also described a manner of implementation in real systems. This article does not include the description of the method used for determining the reliability function, but only theoretical assumptions used in case of identifying functional dependencies.

The Systematized Data Structures Oriented Towards Diagnosis and Prediction

The structured notation using an identification of relations between key process data and functional characteristics of distributed systems has been presented in the paper. Such approach allows obtaining optimal form mapping the structures stored in a PLC‘s memory and also forming reciprocal relationships between hardware devices. Described notation is used at the stage connected with elaboration of diagnostic and prognostic functions. The authors have proposed an universal notation in a domain of sets, which can be used in identification of operational data indispensable in phase connected with a definition of program structures. A particular attention was given to stages connected with optimization necessity of number of main parameters (especially an isolation of a minimal data set required at control and diagnosis stages in case of distributed drives). Revised data sets combine both quantitative and qualitative features, allowing simultaneously for a reconstruction of the structural relationships between real components of distributed systems (a minimization of technical documentation).