Mechatronika Modul 5-8: mechatronické komponenty mechatronické systémy a funkce uvedení do provozu, bezpečnost, vzdálený servis dálková údržba a diagnostika Učebnice (koncept) Evropský koncept pro doplňkovou kvalifikaci mechatronik odborných procovníků v globalizované průmyslové výorbě. EU Projekt č. DE/08/LLP-LdV/TOI/147110 MINOS ++, platnost od 2008 do 2010, EU Projekt č. 2005-146319 Minos, platnost od 2005 od 2007 Tento projekt byl realizován za finanční podpory Evropské unie. Za obsah publikací (sdělení) odpovídá výlučně autor. Publikace (sdělení) nereprezentují názory Evropské komise a Evropská komise neodpovídá za použití informací, jež jsou jejich obsahem. www.minos-mechatronic.eu
Partne i pro provád ní, hodnocení a ší ení výsledk projekt MINOS a MINOS**. - Chemnitz University of Technology, Institute for Machine Tools and Production Processes, Germany - np neugebauer und partner OhG, Germany - Henschke Consulting, Germany - Corvinus University of Budapest, Hungary - Wroclaw University of Technology, Poland - IMH, Machine Tool Institute, Spain - Brno University of Technology, Czech Republic - CICmargune, Spain - University of Naples Federico II, Italy - Unis a.s. company, Czech Republic - Blumenbecker Prag s.r.o., Czech Republic - Tower Automotive Sud S.r.l., Italy - Bildungs-Werkstatt Chemnitz ggmbh, Germany - Verbundinitiative Maschinenbau Sachsen VEMAS, Germany - Euroregionala IHK, Poland - Korff Isomatic sp.z.o.o. Wroclaw, Polen - Euroregionale Industrie- und Handelskammer Jelenia Gora, Poland - Dunaferr Metallwerke Dunajvaros, Hungary - Knorr-Bremse Kft. Kecskemet, Hungary - Nationales Institut für berufliche Bildung Budapest, Hungary - Christian Stöhr Unternehmensberatung, Germany - Universität Stockholm, Institut für Soziologie, Sweden Obsah studijních podklad Minos: moduly 1 8 (u ebnice, cvi ebnice a klí ke cvi ením) zahrnující: základy / interkulturní kompetence, projektový management / fluidní techniku / elektrické pohony a ízení/ mechatronické komponenty / mechatronické systémy a funkce / uvedení do provozu, bezpe nost, vzdálený servis / dálková údržbu a diagnostiku. Minos **: moduly 9 12 (u ebnice, cvi ebnice a klí ke cvi ením) zahrnující: rychlé vytvá ení prototyp / robotiku / migraci / rozhraní. Všechny moduly jsou dostupné v následujících jazycích: n m ina, angli tina, špan lština, italština, polština, eština a ma arština. Pro více informací prosím kontaktujte: Technical University Chemnitz Dr. Ing. Andreas Hirsch Reichenhainer Straße 70, 09107 Chemnitz Tel.: + 49(0)0371 531-23500 Fax.: + 49(0)0371 531-23509 Email: wzm@mb.tu-chemnitz.de Internet: www.tu-chemnitz.de/mb/werkzmasch www.minos-mechatronic.eu
Mechatronika Modul 5: mechatronické komponenty Učebnice (koncept) Wojciech Kwasny Andrzej Blazejewski Wroclaw University of Technology, Polsko Evropský koncept pro doplňkovou kvalifikaci mechatronik odborných procovníků v globalizované průmyslové výorbě. EU Projekt č. DE/08/LLP-LdV/TOI/147110 MINOS ++, platnost od 2008 do 2010, EU Projekt č. 2005-146319 Minos, platnost od 2005 od 2007 Tento projekt byl realizován za finanční podpory Evropské unie. Za obsah publikací (sdělení) odpovídá výlučně autor. Publikace (sdělení) nereprezentují názory Evropské komise a Evropská komise neodpovídá za použití informací, jež jsou jejich obsahem. www.minos-mechatronic.eu
Mechatronické komponenty Minos Obsah:... 7... 7... 8... 8... 10...11...11... 14... 15... 17... 17... 18... 19... 20... 21... 22... 23... 24... 25... 27... 28... 29 3
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Mechatronické komponenty Minos... 79 4.1 Charakteristika konstrukce... 79 4.2 Fotoelektrické elementy... 81... 81... 81... 83 4.2.2 Fotoemitor... 85... 86... 89 4.2.3 Fotodetektory... 91 4.2.3.1 Fotodiody... 91... 94... 95... 96... 97... 97... 99... 102... 104... 104... 106... 106... 107... 109...112...114...115...115...116... 120... 121... 121... 124... 126... 126... 127... 129 5
Minos Mechatronické komponenty... 131... 131... 132... 132... 135... 137... 138... 139... 140... 143... 144... 144... 145... 147... 148... 149 6
Mechatronické komponenty Minos 1.1 Základní informace OBJEKT GENERÁTOR VÝSTUPNÍ SYSTÉM 7
Minos Mechatronické komponenty E L E C E= E L + E C - - I I max 8
Mechatronické komponenty Minos 0 Henrry] Farad] amplituda. 9
Minos Mechatronické komponenty Q 10
Mechatronické komponenty Minos - - amplituda amplituda 11
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Mechatronické komponenty Minos n - r n - n S r n. S a n a n n D 13
Minos Mechatronické komponenty - - ocel St37 chrom 14
Mechatronické komponenty Minos - n D D 15
Minos Mechatronické komponenty - n - f = 1/(t 1 + t 2 ) - 16
Mechatronické komponenty Minos - - - délka 17
Minos Mechatronické komponenty - - - - 18
Mechatronické komponenty Minos - 19
Minos Mechatronické komponenty - - L do diskriminátoru. R. 20
Mechatronické komponenty Minos proud 21
Minos Mechatronické komponenty - GENERÁTOR SYSTÉM VÝSTUPNÍ SYSTÉM proud 22
Mechatronické komponenty Minos U 0,1U D U - R L U - NONC NP NO a NC. PNP NPN 23
Minos Mechatronické komponenty - R L. Sen- - 24
Mechatronické komponenty Minos - 25
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Mechatronické komponenty Minos - R p. Hodnota odporu R p P min P=U 2 I p 27
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Mechatronické komponenty Minos - - elektrody potenciometr DETEKTOR VÝSTUPNÍ SYSTÉM 31
Minos Mechatronické komponenty - S - plocha elektrody 0 r 32
Mechatronické komponenty Minos - - - 33
Minos Mechatronické komponenty obal 34
Mechatronické komponenty Minos - 35
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Mechatronické komponenty Minos - - 37
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Minos Mechatronické komponenty Materiál alkohol bakelit mramor polyamid polyethylen polypropylen polyester porcelán sklo r n n materiál ocel plyn PVC PE keramika 40
Mechatronické komponenty Minos - - - 41
Minos Mechatronické komponenty Mohou: 42
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Mechatronické komponenty Minos 3.1 Základní informace - - OBJEKT GENERÁTOR DETEKTOR 45
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Minos Mechatronické komponenty 1 2 OBJEKT SENZOR 1 2 48
Mechatronické komponenty Minos Teplota: - Tlak: ± ± tlak 1013 hpa teplota 49
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Mechatronické komponenty Minos - -12 - - - keramická deska 51
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Minos Mechatronické komponenty - i e e amplituda impulsu T i i e 58
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Minos Mechatronické komponenty - - - n 60
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Minos Mechatronické komponenty ± ± 90 64
Mechatronické komponenty Minos kapalin 65
Minos Mechatronické komponenty 1 1 dosáhne 1 66
Mechatronické komponenty Minos 67
Minos Mechatronické komponenty plocha 68
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Mechatronické komponenty Minos 71
Minos Mechatronické komponenty konec 72
Mechatronické komponenty Minos - stupni propustnosti 73
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Mechatronické komponenty Minos 4 Optoelektronické senzory 4.1 Charakteristika konstrukce - 79
Minos Mechatronické komponenty - 80
Mechatronické komponenty Minos 4.2 Fotoelektrické elementy 4.2.1 Fyzikální základy
Minos Mechatronické komponenty
Mechatronické komponenty Minos Odraz Absorbce Optický lom
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Mechatronické komponenty Minos 4.2.2 Fotoemitor - 85
Minos Mechatronické komponenty ma 86
Mechatronické komponenty Minos 87
Minos Mechatronické komponenty intenzita 88
Mechatronické komponenty Minos - 89
Minos Mechatronické komponenty Intenzita 90
Mechatronické komponenty Minos 4.2.3 Fotodetektory 4.2.3.1 Fotodiody - - - r
Minos Mechatronické komponenty kontakt kontakt plocha
Mechatronické komponenty Minos - - Kontakt elektrické pole kontakt
Minos Mechatronické komponenty - A a I A
Mechatronické komponenty Minos Délka Intenzita 95
Minos Mechatronické komponenty 4.2.3.4 Fototranzistory - 96
Mechatronické komponenty Minos Emitor Emitor 97
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Minos Mechatronické komponenty 4.4 Zpracování signálu - Intenzita
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Mechatronické komponenty Minos - Hystereze H
Minos Mechatronické komponenty 4.4.4 Pracovní vzdálenost
Mechatronické komponenty Minos -
Minos Mechatronické komponenty -
Mechatronické komponenty Minos horizontální polarizátor emitor trojným zrcadlem vertikální polarizátor
Minos Mechatronické komponenty - - optická osa optická osa aktivní oblast
Mechatronické komponenty Minos - MAX MAX - -
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Mechatronické komponenty Minos - -
Minos Mechatronické komponenty paprsek paprsek paprsek
Mechatronické komponenty Minos 4.5.4 Senzory s optickými vlákny 4.5.4.1 Optické vlákno - n
Minos Mechatronické komponenty
Mechatronické komponenty Minos optické vlákno optické vlákno hlava senzoru
Minos Mechatronické komponenty - optického vlákna výstup objekt optického vlákna výstup objekt senzorová hlava
Mechatronické komponenty Minos - -
Minos Mechatronické komponenty - - výstupní signál: OFF objekt výstupní signál: ON výstupní signál: OFF výstupní signál: ON objekt výstupní signál: ON výstupní signál: OFF objekt objekt
Mechatronické komponenty Minos 4.6.2 Sepnutí výstupu senzoru - -
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Mechatronické komponenty Minos 5 Magnetické senzory - - - -
Minos Mechatronické komponenty 5.2 Teoretické základy 5.2.1 Magnetické pole - N S - - H B r
Mechatronické komponenty Minos diamagnetika paramagnetika - magnetické domény -
Minos Mechatronické komponenty - B 0 B pole pole
Mechatronické komponenty Minos - - mezera kontakt
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Mechatronické komponenty Minos V H pole I C C /d -
Minos Mechatronické komponenty AMR tického pole H I R M - R M0 R M permalloy
Mechatronické komponenty Minos - -
Minos Mechatronické komponenty - NC NO MAX MAX
Mechatronické komponenty Minos -
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Mechatronické komponenty Minos 5.4 Hallovy senzory V H - - - magnet detektor výstupní systém
Minos Mechatronické komponenty 5.5 Speciální magnetické senzory 5.5.1 Magnetorezistivní senzory M M - systém
Mechatronické komponenty Minos 5.5.2 Wiegand senzor - detektor výstupní systém detektor výstupní systém
Minos Mechatronické komponenty
Mechatronické komponenty Minos 5.5.3 Magnetické senzory s jedním magnetem - - detektor výstupní systém
Minos Mechatronické komponenty - - - - senzor senzor senzor senzor
Mechatronické komponenty Minos
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Mechatronika Modul 6: mechatronické systémy a funkce Učebnice (koncept) Jerzy Jedrzejewski Wojciech Kwasny Zbigniew Rodziewicz Andrzej Blazejewski Wroclaw University of Technology, Polsko Evropský koncept pro doplňkovou kvalifikaci mechatronik odborných procovníků v globalizované průmyslové výorbě. EU Projekt č. DE/08/LLP-LdV/TOI/147110 MINOS ++, platnost od 2008 do 2010, EU Projekt č. 2005-146319 Minos, platnost od 2005 od 2007 Tento projekt byl realizován za finanční podpory Evropské unie. Za obsah publikací (sdělení) odpovídá výlučně autor. Publikace (sdělení) nereprezentují názory Evropské komise a Evropská komise neodpovídá za použití informací, jež jsou jejich obsahem. www.minos-mechatronic.eu
Mechatronika Modul 7 :uvedení do provozu, bezpečnost, vzdálený servis Učebnice (koncept) Jerzy Jedrzejewski Wroclaw University of Technology, Polsko Evropský koncept pro doplňkovou kvalifikaci mechatronik odborných procovníků v globalizované průmyslové výorbě. EU Projekt č. DE/08/LLP-LdV/TOI/147110 MINOS ++, platnost od 2008 do 2010, EU Projekt č. 2005-146319 Minos, platnost od 2005 od 2007 Tento projekt byl realizován za finanční podpory Evropské unie. Za obsah publikací (sdělení) odpovídá výlučně autor. Publikace (sdělení) nereprezentují názory Evropské komise a Evropská komise neodpovídá za použití informací, jež jsou jejich obsahem. www.minos-mechatronic.eu
Mechatronika Modul 8: dálková údržba a diagnostika Učebnice (koncept) Jerzy Jedrzejewski Wroclaw University of Technology, Polsko Evropský koncept pro doplňkovou kvalifikaci mechatronik odborných procovníků v globalizované průmyslové výorbě. EU Projekt č. DE/08/LLP-LdV/TOI/147110 MINOS ++, platnost od 2008 do 2010, EU Projekt č. 2005-146319 Minos, platnost od 2005 od 2007 Tento projekt byl realizován za finanční podpory Evropské unie. Za obsah publikací (sdělení) odpovídá výlučně autor. Publikace (sdělení) nereprezentují názory Evropské komise a Evropská komise neodpovídá za použití informací, jež jsou jejich obsahem. www.minos-mechatronic.eu
Remote diagnostics and servicing of mechatronic systems - Textbook Minos Contents: 1 Aims and tasks of remote diagnostics and servicing... 5 2 Idea, components and operation of diagnostic system... 7 3 Idea, components and operation of service diagnosing system... 12 4 Developmental trends... 16 3
4 Remote diagnostics and servicing of mechatronic systems - Textbook Minos
Remote diagnostics and servicing of mechatronic systems - Textbook Minos 1 Aims and tasks of remote diagnostics and servicing Modern machine systems are highly automated. The control systems used in the automation perform their tasks on the basis of instructions (control decisions) generated in microprocessors, processors or computers. Control decisions are taken on the basis of signals from sensors located in executing mechatronic system components, supplying information about the condition of the latter and about the performance of the tasks. The information is used to infer about system operation and task (process) performance correctness and to evaluate the intensity of disturbances resulting in errors which need to be actively minimized and compensated. The control is conducted according to an algorithm which takes into account all the factors having a bearing on the functioning of the mechatronic system and on the performance of the processes. In many cases control functions are carried out intelligently using appropriate AI tools. The diagnosing of a single mechatronic system, whole machines and processes, the supervising of the operation of mechatronic systems and machines and their diagnosing for service purposes can be made intelligent. Malfunctions of and damage to machines during their operation result in high costs of production delays, standstills and repairs for the users. Therefore it has become necessary to continuously monitor machines and processes, forecast disturbances, take measures preventing process quality deterioration and take necessary remedial actions based on the forecasts. Such monitoring is more and more often remote and decisions are taken remotely. Even service functions are performed remotely. In many cases it is necessary to monitor and service remotely since only the manufacturers of mechatronic modules and systems have the required knowledge to identify nonstandard disturbances and their effects and to take service decisions. The task of remote diagnostics is to wirelessly transmit (for a short or considerable distance) diagnostic signals with the required informational content from the diagnosed object to a near or far receiver, a monitoring station or a monitoring centre. A proper inference system, an intelligent advisory system or an expert will assess the disturbances and will take appropriate service decisions, remotely generating forecasts, evaluating the deviations and identifying the degradation of the operating parameters with a required accuracy and probability. The diagnosing system s response are diagnostic inferences which are the basis for taking service decisions. The tasks of a remote servicing system include: - preventing excessive deterioration of mechatronic system (machine and equipment) operating parameters by reducing disturbances and compensating errors; - predicting excessive errors and defects before they occur, whereby remedial action can be taken in a planned and prepared way to keep adverse economic consequences to minimum (intelligent action); - optimum planning of service tasks for operating periods most convenient to the user. 5
Remote diagnostics and servicing of mechatronic systems - Textbook Minos A revolution in remote diagnostics was the development of wireless supply of sensors and wireless reception of their diagnostic signals, whereby the measuring systems could be miniaturized, measurements could be improved and the structure of objects could be penetrated by means of sensors to satisfy diagnostic needs. The connection of sensors to communication networks has resulted in almost limitless possibilities of controlling the diagnosis process using not only single sensors but also groups of sensors. As a result, information from sensors can be used by control, diagnostic and forecasting systems. This is of great significance for the diagnosis of mechatronic system components and modules. 6
Remote diagnostics and servicing of mechatronic systems - Textbook Minos 2 Idea, structure and operation of diagnostic system Diagnostics of machines ensures their precise and reliable operation. The more complex a machine, its mechatronic system and the conducted technological processes are, the larger the number of various disturbances which need to be periodically or continuously monitored and the errors they cause reduced. The higher the precision required of machines (diagnosed objects), the greater the precision and reliability of identification (i.e. the greater the precision of the sensors, the processing of diagnostic signals and transmitting them to a monitor, a control system and a diagnostic or service centre) must be. Thus the design or choice of a proper diagnostic system, software and hardware requires extensive knowledge of machine building, the processes involved, the theory and practice of diagnosis and all diagnostic system components. Diagnostic complexity and precision depends on the effect which the diagnosed parameters of machines have on the latter s work processes. Typical malfunction percentages for a selected machining centre are shown in table 1 and typical quantities to be monitored are presented in Fig. 1. Malfunction location Share [%] Conveying and feeding objects 20.1 DNC system 18.2 Retooling mechanism 14.6 Tool length setting 14.1 Machine tool mechanical assemblies 12.1 Tool damage 6.8 Workpiece clamping 2.6 Fine-tuning control 1.7 Feeding coolant 1.7 Clamping palettes 1.1 NC system 0.9 Problems with chips 0.9 Hydraulics 0.9 Other malfunctions 4.3 Table 1: Malfunction percentages for machining centres 7
Remote diagnostics and servicing of mechatronic systems - Textbook Minos Full diagnostics of such a complex object as an operating machine tool is very difficult and costly. Sensors for continuous or periodic monitoring must be permanently installed within the machine tool structure, which is highly expensive. The sensors are connected by wires and sometimes wirelessly (using proper communication standard) to signal processing circuits. The signals must be explicit, i.e. they should precisely inform about any changes in the monitored quantities and should not be subject to any interference during their transmission to processing circuits. The processed signal is then used in inference which, in a simple case, consists in evaluating the measured quantity against the value proper for the monitored parameter. The result of inference is the basis for the formulation of diagnostic conclusions. For complex phenomena and object behaviours many diagnostic signals must be simultaneously evaluated. Such an inference process can be highly complex and require very complex procedures and algorithms and sometimes artificial intelligence tools: fuzzy logic, artificial neural networks and expert systems. Also the efficiency of the communication system, especially when the diagnosed quantities are critical for system operation reliability (require a quick response), is important. The further away from the signal source the sensor is, the greater the danger that the monitoring system sensitivity may be not high enough and the response time too long. In such cases it may become necessary to employ measurement amplifiers integrated with the sensors, digital filters and proper signal processing. In this way one can greatly increase the measurement resolution. Tool wear Tool chipping Machine force Air temperature and humidity Machine tool temperature Workpiece temperature and geometry Palette clamping force Presence of unmachined workpiece Geometry of unmachined workpiece Tool temperature Geometry deformation Guard closing Vibrations Main drive load Feed drive load Supply voltage Rotation speed Ball screw forces Spindle torgue Oil feed Oil pressure Oil temperature Air pressure Acoustic emission Clamping pressure Feed force Positioning accuracy Axies and connectors Palette clamping force Fig.1: Typical machining centre quantities requiring monitoring 8
Remote diagnostics and servicing of mechatronic systems - Textbook Minos The input data for object diagnostics are: - diagnostic signal properties and acquisition points (sensor locations, the rate of changes and availability for service), - the boundary values of controlled quantities, - dependencies between the generated signal and the disturbances in the performance of an object or a process, - sensors and measuring instruments (sensitivity, complexity, adaptability, numerousness, cost, the degree of automation), - the form of acquired information, - the methods of processing signals, - verification methods, - the method of communicating with receivers, - the strategy of diagnosis, - inference methods. In order to reduce the number of sensors and the complexity of the signal processing system one should use such sensors which can supply much information about the behaviour of an object. Measurement paths can be much simplified and diagnostic information more easily acquired if intelligent converters are used. The structure of an intelligent force converter is shown in Fig. 2. These are usually small-sized units made as MEMS (Micro-Electro-Mechanical Systems) microstructures, which include a sensor with a matching digital amplifier and a microprocessor with stored knowledge for intelligent signal processing. DIN 66348 Force sensor 1 Force sensor 2 Pressure sensor Sampling-storing system a/d converter RS 485 RS 232 Microprocessor Inputs Outputs, Alarm PC Temp. sensor a/c 5 2 6 9 3 Fig. 2: Structure of intelligent force converter 9
Remote diagnostics and servicing of mechatronic systems - Textbook Minos The criteria for designing diagnostics are: - diagnostic signal sensitivity to changes in machine/process performance and information capacity, - the degree of machine/process degradation, - the level of service personnel qualifications, - reliability, - operating costs. A typical unit for diagnosing mechanical objects consists of the following assemblies and components: 1. A measuring system (sensors, matching systems responsible for energy and information matching of signals, diagnostic sockets for retrieving information from the object). 2. Instrumentation amplifiers, a/d converters, channel selectors, I/O ports and other. 3. A digital signal processor (used for calculating diagnostic symptoms). 4. A decision system (incorporating logic converters, voltage level translators, digital comparators and other). 5. An information display system which decodes information and presents it in the form most convenient for the user (monitor, printer, analogue indicators, digital indicators and other). 6. An information storage system (memory: RAM, RAM-DISK, VDISK). 7. Software (operating system, signal processing and analysis, state diagnosis and prediction, functions performed by the diagnostic unit, communication between system layers, system operation management). 10
Remote diagnostics and servicing of mechatronic systems - Textbook Minos A block diagram of the diagnostic unit is shown in Fig. 3. DIAGNOSTIC UNIT Components Diagnostic signal sensors Diagnostic system Diagnostic sockets Processor Multichannel diagnostic signal converter System bus RAM, RAM-DISK, VDISK Keyboard Monitor Printer Software Fig. 3: Block diagram of microprocessor diagnostic unit 11
Remote diagnostics and servicing of mechatronic systems - Textbook Minos 3 Idea, components and operation of service diagnosing system As opposed to the general diagnosing of the operation of an object and the work processes the latter carries out, which informs the user if the disturbances are within permissible limits and if sufficient product accuracy is being achieved, the purpose of service diagnostics is periodic error correction and planned recovery of the correct operating parameters. Service diagnostics consists in tracking the degree of object (machine) degradation in order to apply error correction and compensation or carry out a planned and well prepared repairs during a short standstill at a time convenient for the user. Thus the purpose of service diagnostics is to restore the machine s operating parameters guaranteeing the desired process (product) accuracy. In order to forecast the degradation of machine components one must probe deeper into the wear processes and the mechanism of change of operating parameter values (symptoms of progressing damage) than in general diagnostics. This means that in service diagnostics one must apply extensive up-to-date knowledge about the design and operation of the machine, its precision, disturbances in the precision, error correction and compensation methods and repair techniques and technologies. Service diagnostics capabilities should be generally taken into account already at the machine design stage. This applies particularly to the location in the machine of (intelligent) sensors and components enabling their communication with the user s or manufacturer s diagnosticservicing centre. Also at this stage simulations of the dependencies between diagnostic signals and defects should be carried out, which will facilitate forecasting service activities and determining the needs relating to the structure of the measuring systems. The application of knowledge in this kind of diagnostics involves modelling machine behaviour in the operating conditions, modelling errors in the form of simplified functions suitable for periodic supervision and compensation, limited forecasting and modelling permissible deterioration in machine performance and possible types of damage. These are highly complex activities and require adequate computer hardware and software and highly qualified designers. In many cases one can use dedicated commercial software and diagnostic modules. A typical graph of machine/technological device operating parameter degradation, with the admissible value and the boundary value of the measured signal (diagnostic symptom) marked (indicating whether the machine is or is not functional), is shown in Fig. 4. If the symptom exceeds admissible value U d, this means that the diagnosed device is no longer fully functional but it can be operated for a certain time, i.e. it is still capable of performing its functions. If the symptom exceeds boundary value U g (which marks the ultimate date for doing repairs), this means that it is no longer fit for use. Serviceability and unserviceability areas can overlap to some extent. In the overlapped area the device is not fully functional but still serviceable (Fig.5). 12
Remote diagnostics and servicing of mechatronic systems - Textbook Minos Uniserviceable Signal/symptom U g Ud Not fully functional but serviceable Serviceable U g - Boundary value Ud- Admissible value Structure parameter/technical condition Serviceable Functional Not fully functional Unserviceable Fig.4: Classification of technical condition of machines and devices Functional Serviceability area Not fully functional but serviceable Unserviceable Nonfunctionality area Fig. 5: Areas of technical condition of machines and devices 13
Remote diagnostics and servicing of mechatronic systems - Textbook Minos The range in which in technical object operation is aided with knowledge processing and diagnostics is shown in Fig. 6. The range covers a very wide spectrum of analyses and the use of AI tools. DIAGNOSTIC TASK (real objects) MECHANICAL MODELS (structure and condition characteristics) PHYSICAL MODEL MATHEMATICAL MODEL IDENTIFICATION OF MODELS Qualitative description Explanatory description Quantitative description STRUCTURAL MODEL - wear dynamics HOLISTIC MODEL Types of models: deterministic probabilistic fuzzy STRUCTURAL MODEL - wear evolution SYMPTOM MODEL DIAGNOSTIC MODEL HOLISTIC DIAGNOSTICS ELECTRICAL DIAGNOSTICS INFERENCE MODELS deterministic probabilistic fuzzy neural ekxpert other DIAGNOSIS (current/future) SYMPTOM DIAGNOSTICS CRITERIA division of models accuracy limit states effectiveness other Fig. 6: Object diagnostic modelling capabilities 14
Remote diagnostics and servicing of mechatronic systems - Textbook Minos The way in which relationships between a symptom and a defect are sought (which is the aim of service diagnostics) is shown in Fig. 7. This requires highly complex operations on models: model reversing, complicated testing of models sensitivity to defects, training data generation, creating adaptational models and building diagnostic relations. Thanks to the use of such simulation techniques of acquiring symptom-defect relations the operators of the device being diagnosed are able to view on the monitor not only information about the occurrence of a failure but also defect identification data. CLASSICAL METHOD DEFECT MODEL SYMPTOM MODEL REVERSAL METHOD SYMPTOM REVERSED MODEL DEFECT Reversal of models by training adaptational systems (dedicated algorithms, artificial neural network) Building object models Testing model s sensitivity to defect Training data generation Building adaptational models Training adaptational systems Building diagnostic relations Fig.7: Simulation techniques of acquiring diagnostic relations: classical and based on object model reversal methodology 15
Remote diagnostics and servicing of mechatronic systems - Textbook Minos 4 Developmental trends Remote diagnostics and servicing have strong economic reasons since they contribute to longer product life. Therefore attempts to increase product life span will translate into the development of diagnostics and supervision. In addition, as the globalization of manufacturing increases so does its dispersion whereby it becomes necessary to employ remote diagnostics and servicing in order to significantly increase the reliability of mechatronic systems, technological processes and the manufactured products. This means that diagnostic system modularity will continue to be developed and an ever larger number of diagnostic functions will be carried out by intelligent sensors. This will naturally be accompanied by the miniaturization of measuring systems and their integration with the processes responsible for signal processing and diagnostic inference. Also reliable technologies for remotely supplying the systems with power and transmitting the information generated in them to a higher decision level to diagnostic-servicing centres will continue to be developed. New, more advanced communication standards and decision algorithms aided with AI tools will be used for this purpose. The development of remote diagnosing and servicing of machine systems tends towards full coverage of the latter and towards total supervision and servicing based on forecasts. 16