SUMMARY OF THE HABILITATION THESIS

Transcription

1 Appendix No. 3 SUMMARY OF THE HABILITATION THESIS presenting an overview of accomplishments and scientific achievements in particular referred to in article of the Act on Academic Degrees and Title and Degrees and Title in the Arts. Dr. Eng. Jarosław Konieczny jaroslaw.konieczny@agh.edu.pl Krakow, October 2014 Department of Process Control Faculty of Mechanical Engineering and Robotics AGH University of Science and Technology 30 Mickiewicza Ave., Kraków, B-2,

2 Spis treści 1. Name and surname Diplomas and scientific degrees Information on previous and current employment Scientific achievements The title of scientific achievement List of scientific works representing the monothematic cycle of publication Characteristics of the scientific achievement Discussion of works belonging to the monothematic publication cycle Modelling the controlled vibration reduction systems Quality indicators used to rating controlled suspensions The synthesis of control laws for selected suspensions The results of laboratory tests of selected controlled suspension structures The applicant's individual contribution to the development of scientific discipline and contribution in percentage Summary Other scientific and research achievements Author and co-author of scientific publications Participation in thematic conferences Patents Contribution to scientific research projects execution Participation in contracts with industrial centres Foreign internships Didactic activities Organisational activities Editor and reviewer in scientific journals Quotation indexes Strona 2 z 39

3 1. Name and surname Jarosław Konieczny 2. Diplomas and scientific degrees specifying the name, place and year they were obtained as well as the title of the doctoral thesis. Title: Technician of electronics Tadeusz Kosciuszko, Energy Technical Secondary School in Cracow Specialization: General electronics Year of graduation: Degree: Master of Engineering AGH University of Science and Technology, Faculty of Mechanical Engineering and Robotics, Department of Process Control Field of study: Mechanics and Machine Construction Specialization: Measurement systems and Automatic Control MSc. thesis title: Adaptive control in active mechanical vibrations reduction systems Supervisor: Professor Janusz Kowal, AGH University of Science and Technology Date of thesis submission: Degree: Doctor of Engineering AGH University of Science and Technology Faculty of Mechanical Engineering and Robotics In the field of Automatics and Robotics Specialization: Control of mechanical systems Doctor dissertation entitled: Active vehicle suspension with limited energy consumption Supervisor: Professor Janusz Kowal, AGH University of Science and Technology Reviewed by: Professor Zenon Hendzel, Ignacy Lukasiewicz Technical University of Rzeszow Reviewed by: Professor Bogdan Sapinski, AGH University of Science and Technology Thesis defence date: Thesis distinguished with honours by the resolution of the Board of the Faculty of Mechanical Engineering and Robotics of the AGH University of Science and Technology 3. Information on previous and current employment Since October 1998 until 2 October 2006 assistant in the Department of Process Control of the Faculty of Mechanical Engineering and Robotics of the AGH University of Science and Technology. In years academic lecturer in the University of Business and Enterprise in Ostrowiec Świętokrzyski, the post of teaching assistant. The scope of duties included didactic activities (lectures and laboratory classes whose curricula were developed by the TA himself) of the following subjects: Introduction to IT, Data Bases, Calculation Strona 3 z 39

4 Sheet, Office Work Automation, WWW page development, Computer Networks and Local Computer Networks. In years own business under the commercial name of INFOKON Jarosław Konieczny. The object of business operations was to offer IT software and hardware trainings, IT services, design and implementation of automation systems. In years teacher in the Private Medical Postgraduate School of the Pharmaceutical Technique in Cracow. The scope of duties included teaching classes in the subject 'Information and computer techniques in a pharmacy' pursuant to the author's own curriculum. Since 2 October 2006 adjunct (assistant professor) in the Department of Process Control of the Faculty of Mechanical Engineering and Robotics of the AGH University of Science and Technology. 4. Scientific achievements Scientific achievements pursuant to art of the Act of 14 March 2003 on Law on Academic Degrees and Title and Degrees and Title in the Arts (Official Journal of Laws No. 65, item 595 as amended): 4.1. The title of scientific achievement The scientific achievement which constitutes a significant input into the development of the science area: Automation and Robotics defined in art of the Act, I hereby present a cycle of publications devoted to one subject under the collective title of: Analysis and Synthesis of Vibration Control Systems with Emphasis of Energetic Parameters List of scientific works representing the monothematic cycle of publication The list of monothematic cycle of publications constituting my scientific achievement includes the following articles published in domestic and foreign scientific journals 1 : [1] J. Konieczny, J. Kowal, J. Pluta, A. Podsiadło, Laboratory research of the controllable hydraulic damper, Engineering Transactions. 54 (2006) punkty MNiSW: (4 point), liczba cytowań WOS (0), PP (10) [2] J. Konieczny, Modelling of the Electrohydraulic Full Active Vehicle Suspension, Engineering Transactions. 56 (2008) punkty MNiSW: (4 point), liczba cytowań WOS (0), PP (9) 1 The IF values have been determined based on the '5-Year Impact Factor' as specified by Thomson Reuters in Journal Citation Reports. The points awarded by the Ministry of Science and Higher Education (MNSiW) comply with the list of the publication's year. The number of times cited has been given pursuant to the following bases: Web of Science (WOS) and Publish or Perish (PP). Declarations by co-authors of the monothematic cycle of publications specifying their individual contribution into the work have been presented in appendix 6 to the application. Strona 4 z 39

5 [3] J. Konieczny, Laboratory tests of active suspension system, Journal of KONES. 18 (2011) punkty MNiSW: (9 point), liczba cytowań WOS (0), PP (2) [4] J. Konieczny, J. Kowal, W. Raczka, M. Sibielak, Bench Tests of Slow and Full Active Suspensions in Terms of Energy Consumption, Journal of Low Frequency Noise, Vibration and Active Control. 32 (2013) IF: 0,283, punkty MNiSW: (15 point), liczba cytowań WOS (1), PP (2) [5] M. Sibielak, J. Konieczny, J. Kowal, W. Raczka, D. Marszalik, Optimal Control of Slow- Active Vehicle Suspension - Results of Experimental Data, Journal of Low Frequency Noise, Vibration and Active Control. 32 (2013) IF: 0,283, punkty MNiSW: (15 point), liczba cytowań WOS (1), PP (3) [6] M. Sibielak, W. Raczka, J. Konieczny, J. Kowal, Optimal control based on a modified quadratic performance index for systems disturbed by sinusoidal signals, Mechanical Systems and Signal Processing. Artykuł złożony do publikacji. IF: 2.623, punkty MNiSW: (45 point), liczba cytowań WOS (0), PP (0) [7] J. Kowal, J. Pluta, J. Konieczny, A. Kot, Energy Recovering in Active Vibration Isolation System Results of Experimental Research, Journal of Vibration and Control. 14 (2008) IF: 1.736, punkty MNiSW: (20 point), liczba cytowań WOS (6), PP (12) [8] M. Sibielak, W. Raczka, J. Konieczny, Modified Clipped-LQR Method for Semi-Active Vibration Reduction Systems with Hysteresis, Solid State Phenomena. 177 (2011) punkty MNiSW: (20 point), liczba cytowań WOS (5), PP (8) [9] W. Raczka, M. Sibielak, J. Kowal, J. Konieczny, Application of an SMA Spring for Vibration Screen Control, Journal of Low Frequency Noise, Vibration and Active Control. 32 (2013) IF: 0,283, punkty MNiSW: (15 point), liczba cytowań WOS (1), PP (3) [10] J. Konieczny, J. Pluta, A. Podsiadło, Technical condition diagnosing of the cableway supports foundations, Acta Montanistica Slovaca. 13 (2008) IF: 0.133, punkty MNiSW: (2 point), liczba cytowań WOS (3), PP (4) Comment: The total Impact Factor (IF) for articles published in journal [1-10] with the exclusion of item [6] amounts to Sum of the Times Cited specified according to WOS amounts to (17), and according to PP it is (53). The said factors have been given only in reference to the monothematic cycle of publications. Strona 5 z 39

6 4.3. Characteristics of the scientific achievement Introduction to vibration control The idea of active vibration control methods has been formulated in the 30's of the 20th century and applied to reduce the intensity of unwanted sounds. Due to the development of signal processing methods, only since the 80's of the 20th century, has it been undertaken in practical applications of mechanical vibration reduction. In Poland in 1993 the first scientific conference on 'Active Noise and Vibration Control Methods' MARDiH was organised and it included into its scope the issues of active vibration control methods. The on-going technological progress opens wider possibilities concerning vibration control systems, in particular in the field of implementation of new mechatronic actuator which converts energy into motion. The main factors limiting in practice the use of vibration control systems are their high execution and exploitation costs. Therefore I started to work on identifying the source of these high exploitation costs, by taking into account primarily the power consumption of these systems. I launched research on how to limit the demand for external energy by means of modifying the analysed systems' structure and how to minimise the energy consumption by choosing and tuning the appropriate control laws. The constant need to develop vibration control techniques is discussed by the authors of the 'Aeronautical Technologies for the Twenty-First Century' publication. The authors of that monograph express their hopes for a quick development of active vibration control methods; owing technologies such as new solutions of high frequency sensors and actuators as well as the development of control theories, going in the direction of dedicated control laws for active vibration control methods. Vibration control is an area of science covering a set of issues related to the vibration systems in which, to control them, an additional controlled actuator has been introduced. Controlling the said actuator is executed in compliance with the control law, which could be selected so as to: reduce (control) the vibrations to the greatest extent possible, gain them or control them at a strictly defined level. To perform the vibration control task it is necessary to introduce into the system an additional element which converts energy into motion, called the actuator. In the above-mentioned monothematic cycle of publications, the majority of my papers is about the vehicle vibration control with the use of controlled suspension. The remaining works refer to vibration control at an appropriate level and methods of rating its quality. A significant part of my works concerns the modelling, both of actuators used in vibration control systems, and the entire systems of controlled suspensions. Historically speaking, suspension is classified as passive or controlled; the latter on the other hand are either semi-active or active. If no energy is supplied to the suspension from the outside in order to minimise vibrations, we say it is passive. On the other hand the controlled suspensions can be classified according to two criteria: according to the input energy supplied to them and according to the frequency band of the actuator operation. If we supply external energy to drive the system generating force in order to vibrations control, we are talking about an active suspension. In the case in which the said energy is Strona 6 z 39

7 supplied in order to control the suspension parameters, i.e. the stiffness (spring constant) or viscous damping, we are dealing with a semi-active suspension. The classification made according to the frequency band defines the relations between the excitation frequency and the cutoff frequency specifying the actuator operation range. In the course of recent years there have appeared many classifications of controlled suspensions. The author is inclined to extract five types of controlled suspension, arranged pursuant to their external energy demand: 1. adaptive suspension, 2. semi-active suspension, 3. load-levelling suspension, 4. slow-active suspension (serial structure), 5. full-active suspension (parallel structure). The first two types are suspensions, in which an vibration reduction efficiency can be obtained only owing to a controlled change of parameters such as viscous damping or spring constant. In these systems the energy supplied to the controlled suspension is used only to change the parameters of the vibrating system. The difference between these two types of suspension is in the frequency range of the actuators operations range. The adaptive systems are limited only to slow changes (below 5 Hz) and adjust to them for example they adapt to the type of surface: from the gravel to asphalt one. On the other hand, semi-active suspensions reduce vibrations within a wide frequency range and its actuator is characterised by an operational range even up to 40 Hz. The suspension of the load-levelling, slow-active and full-active types are characterised by the fact that the energy driving the system generating power is used to reduce the vibration amplitude. The efficiency of vibration reduction in the case of these three suspension types is higher than in the case of the adaptive or semi-active systems. The first system in which we are dealing with supplying energy to the actuator of an active suspension in order to generate forces in the opposite direction as disturbances from road irregularities is the load levelling system. In this system, the energy delivered to drive the actuator is transformed into the work in order to compensate the suspension pitching (rolling) or deflection in the steady state. The other systems in which actuators generate the power directed to reduce of vibrations are the slow-active and full-active suspensions. The basic difference between these structures is the location of the actuator. In the full-active structure the actuator is connected to a spring in a parallel way while in the slow-active one in a series manner. The construction of these structures results in that - for the slow-active system - the expected frequency band of the actuator's operational frequency is limited in comparison to the fullactive structure. Due to the potentially higher efficiency of isolation, in my works I focused mainly on two type of suspensions: the full and slow-active one. The application of active vibration control systems in vehicles appears to be related to a high demand for external energy. This is the most important parameter limiting the Strona 7 z 39

8 wide use of controlled suspension in vehicles, therefore in my research I paid special attention to energetic issues. In the publications on this topic there are a number of active suspension control strategies discussed, yet most solutions focus on the efficiency of vibration isolation. In the case of classic passive wheeled vehicle suspensions, the discussed issues are also the handling of the vehicle, its road holding and road surface protection. However, there are few papers discussing the issue of controlled suspensions and the issue of demand for energy of active control systems, in particular in the context of vibration isolation efficiency. The majority of research on the demand for external energy for active vehicle suspension is limited to simulation research. In the controlled suspension systems for the car industry, the most important control task is to reduce the dynamic effect resulting from road roughness. In the vibration control system, the said effects are treated as a disturbances. Depending on the type of the object model used, the disturbances is treated as a displacement or a force acting to the controlled object, i.e. the active suspension. It is considered as a random disturbances with a normal distribution and the power spectrum density function dependant on the class of road. For this reason it is important to take into consideration the variable character of disturbances at the stage of the control law synthesis. An additional problem are the different locations of the disturbances operation and the controlling force generated by the active element. In literature such systems are called the 'non-collocated systems'. Disturbances for the controlled vehicle suspension are usually difficult to measure, while the active actuators used in practice have limited dynamics and are often described by non-linear differential equations. The techniques of synthesising vibration control laws are applied also for vibration generators. The vibration system analysis and quality rating methods, as proposed in the monothematic publication cycle, are used also in diagnostics systems, for example, in building constructions. The author's individual contribution In the monothematic publications cycle I prepared a new and original approach (so far not published in the world literature) to analyse and synthesise vibration control systems, in particular vehicle suspension. This approach, apart from vibration control efficiency, takes into account also the external energy supplied to the active element, which so far was not taken into account in active suspension systems. The presented methods of analysis and synthesis of control laws have been implemented by myself into real time controllers for laboratory objects and I tested them by means of experiments. This confirmed their efficiency in practical vibration control tasks. The significant of the presented scientific achievement for the development of science in the field of signal analysis, control theories and mechanics is in defining a set of own quality indicators used to rating vibration control systems. These indicators make it possible to rating nonlinear vibration control systems, both with respect to vibration transmission as well as demand for external energy, necessary to drive the active element. Strona 8 z 39

9 They are the basis for formulating control laws. Due to their features, the vibration control systems are subject to specific, opposing assessment criteria. On the one hand in order to maximise the reduction or gain of vibrations in the whole range of the analysed frequencies one needs the highest energy possible to drive the actuator. On the other hand, however, the high demand for external energy constitutes an important factor limiting in practice the widespread application of vibration control systems. For wheeled vehicles the other facts which are opposing to the above-mentioned are: vehicle handling, road holding and road surface protection. Finding a compromise between those opposing criterion is the basic task executed by an active control system. In my papers submitted as the monothematic publication cycle I presented, among others, an analysis and research on two different structures of vehicle controlled suspension: the slow-active and the full-active one. I proved that, due to the efficiency of vibration reduction (control), the choice of the suspension mechanical structure (provided that the object is controllable) is of secondary importance. However, the research conducted by me demonstrates also that these structures differ with respect to their demand for energy from an external source. Active elements used in the analysed suspensions have been modelled with consideration to their nonlinear character. The actuators used in vibration control systems are usually described with nonlinear differential equations. Frequently also the controlled object in itself is nonlinear; for this reason the synthesis of effective control algorithms is quite a significant challenge in itself. In such a situation, the synthesis of nonlinear control systems is the first obvious solution. Defining the optimum control law in the case of nonlinear features occurring in the analysed execution systems is a task with high computational complexity. Due to the performance computing of the controller, it is not an effective approach to the control process implementation. The most common method of solving the issue of control law synthesis for nonlinear object is the linearization of the model. For the analysed controlled vehicle suspension with a hydraulic actuator, controlled by a flow servo-valve, I made a synthesis of nonlinear mathematical models. Unlike in the classic linearization method at the operating point, I proposed the method of linearization along the admissible trajectories of the system in the work interval for real scope values of changes of the limited state vector. In the situation in which the nonlinear function is not differentiable at the operating point, the proposed method is a solution to the problem of linearization of a nonlinear suspension model. Moreover, due to the linearization in the working range, the proposed method gives a better approximation of the nonlinear model by the use of the linear model. The achievements presented in the monothematic cycle of publications have been confirmed by experiments and they constitute my significant research contribution into the development of the science field of Automation and Robotics. These achievements are related mainly to the practical implementation of the proposed control methods. I developed test stands that enable the verification by means of experiments of my theoretical and simulation research. They include the preparation of the measurement and control methods as well as their implementation into real time controllers (RT) and Strona 9 z 39

10 reprogrammable FPGA systems. The FPGA systems have been used for the hardware realization of some selected time-critical algorithms due to their execution time and the reliability of their controller's operation. The designed vibration control systems were tested at special rigs, designed specifically for testing controlled suspension; I am the person who conceived and designed them. Laboratory tests of the physical models of vibration control models have confirmed the high efficiency of the proposed approach, both for the reduction systems and the vibration control. Detailed description of results obtained in the monothematic cycle have been presented below, in the part called 'Discussion of works belonging to the monothematic publication cycle'. The works listed in the monothematic cycle have been published (except for [6], which is being in publishing process as I am drafting this application) and in international scientific journals, whose field of interest were the issues discussed in individual publications. The cycle has the following structure: articles (3 of them) published in highly-rated periodicals under the aegis of the Polish Academy of Sciences (these are the publications dating prior to the Regulation of the Minister of Science and Higher Education of on the assessment criteria for a person applying for the degree of habilitated doctor). articles (in the amount of 6) in journals listed in the base of Journal Citation Reports (JCR), the so-called Philadelphia list, one article in a topical scientific journal, published in part B of the list of periodicals by the Ministry of Science and Higher Education for Discussion of works belonging to the monothematic publication cycle The works presented here constitute a synthesis of my research results in years An inspiration for my scientific and research works, after obtaining the title of Doctor of Science, was the multi-annual research programme implemented in the Department of Process Control. I planned the monothematic cycle of publications so that the result of my research be the knowledge, practice and experience necessary to design, execute and run correctly a controlled vehicle suspension. While I conducted my research, mainly in the framework of research projects, there were many works were published whose results allowed me to apply and implement in practice the vibration control systems. An important problem discussed in my publications related to vibration control techniques is taking into account the energy dependency, both at the stage of synthesising the control law and demand for external energy necessary to achieve the assumed effect of vibrations control. Energy issues are hardly ever discussed in papers on vibration control. In the Web of Science base, out of almost 3000 papers on vibration control, there are only 345 touch the energy issues. Among those 345 works, the majority of energy analysis relates to energy dispersion in vibration control systems or it harvesting; the aspect of demand for external energy is omitted in most papers. This, however, is one of the main elements determining the exploitation costs of controlled suspensions. Strona 10 z 39

11 In my works presented as the monothematic publication cycle, one can distinguish common elements, characterised by common approach to the execution of a vibration control system. I have extracted four stages of a vibration control system development: 1. modelling the controlled vibration reduction systems, 2. defining quality indicators for formulating and analysis the control law, 3. synthesis of the control law, 4. simulation and experimental tests on physical models with the application of real controllers. Below are characteristics of the implemented monothematic cycle with a view to the above-mentioned stages of vibration control system development. Modelling the controlled vibration reduction systems In papers [1,2] I focused on the modelling both of the active elements applied for the controlled vibration reduction system and for the entire layout of controlled system. Familiarity with mathematical models determined by analytical means as well as by identification of experimental models is extremely important in particular during the synthesis of control laws for active and semi-active vibration control systems according to the proposed research method. In paper [1] I discussed the issue of hydraulic vibration dampers used in various types of vehicle suspension. My considerations were made mainly about the influence of parameters related to the adjusting of the damping force on the system properties and the amounts of energy dispersed. I conducted my research on the example of an experimental damper with controlled parameters. In this publication I presented the methods of how to describe the properties of dampers in the form of parametric models and their identification methods. The core part of my paper [1] is the description of laboratory tests. I illustrated them with a number of features making it possible to compare the static and dynamic properties of a controlled damper. My own contribution is the proposed, and described in this paper, method of determination the vicarious damping factors based on energy dependency of the tested laboratory dampers. In order to determine the parameters presented in the operation of models, I developed a measurement and control system. My research was conducted with the use of such programming environments as Matlab, LabVIEW. The application of a shock absorber with controlled damping force enables one to shape the frequency characteristics of the suspension. Owing to a variable (controlled) force one can obtain the required shape of characteristic within the scope limited by nominal parameters. As I have already mentioned, the most frequently considered system of active vehicle suspension are the parallel and serial structure (the full-active and slow-active one). An advantage of the proposed structures is a possibility for them to work (to a limited range) in the case of failure of the active system. In the case of a parallel structure, the system must be designed in such a way so that, if a failure happens, the active element generates the smallest possible force. On the other hand, in the case of a serial structure, the failure of the active element should result in making the actuator stiff. Strona 11 z 39

12 The full-active structure, called also the broadband one, requires the operation of an active system within a wide range of frequencies, from 0 to 20 Hz. The broadband frequency character of the active system operation results in high demand for power from an external power source. An advantage of this structure is that it does not require any developments of the suspension strut construction. On the other hand the serial structure, called also the narrowband one, makes it possible for the active system to work below the theoretical vibration isolation condition ( for the passive part of the suspension, usually up to 5 Hz. Above this frequency, the function of vibration reduction is to a great extent taken over by the passive spring. This type of construction makes it possible to reduce the demand for external power compared to the parallel structure system. The most important disadvantage of a suspension whose active element in a series with the spring is increasing the height of the suspension strut. In order to maintain the suspension stroke, both the spring and the active element must have their strokes equal to the planned suspension stroke. Another disadvantage of this type of suspension is its high sensitivity to changes of the sprung mass, which with the use of small spring constant could lead to unstable work of the system. In my works on the suspension systems with a slow-active structure, I used a pneumatic spring connected in a serial manner with an electro-hydraulic active element (actuator). The above described active suspension structures require control systems. I have formulated mathematical models for the proposed structures in order to synthesise the control laws. In paper [2] I proposed a mathematical model of a parallel structure taking into consideration the dynamic properties of an active element described by nonlinear differential equations. The above-mentioned mathematical model was written down in the form of state equations, from which I separated the linear and nonlinear part. I identified parameters of the constructed physical model of the suspension. I compared the results of computer simulations made pursuant to the phenomenological model with the results of experimental tests of a laboratory model with an active suspension of the full-active structure. The laboratory verification confirmed the correctness of the proposed model and allowed to fine-tune it in order to obtain a model with a required precision, enabling the synthesis of a control law. In the last part of the article I determined the static and dynamic properties of an open suspension system (without a controller) on the basis of the obtained models. Extensive parts of the work [3] were presented during the ACTIVE 2009 international conference in Ottawa and on the XLIX Symposium ' Modelowanie w Mechanice ' in In this paper I focused on the issues of active vibration reduction in vehicles and on experimental tests of the used controlled suspension structure. My objective was to prepare an active vehicle suspension, which with limited external energy use would ensure high efficiency of vibration control and vehicle stability. I have presented a synthesis of control laws for an active vehicle suspension with a parallel structure. I compared the control systems of an active vehicle suspension with limited parameters of the power supplier. Strona 12 z 39

13 A very important element of this work are the laboratory tests on the designed active vehicle suspension in the form of a quarter vehicle model. In the course of these tests I determined the demand for external energy with various control algorithms of active element. As the quality indicator for the designed and constructed suspension, apart from the efficiency of vibration isolation system, I took into account the stability of the system (vehicle suspension) and the demand for external energy. The results of research for the full-active (parallel) structure have been presented in work [3] I compared in [4] with the tests results for the slow-active (serial) structure. In the serial slow-active structure I used the same active element and I applied the same control laws. Therefore the adopted mathematical description of the active element (actuator servo-valve) was the same. The models of entire slow- and full-active suspensions used in this paper [4] have been presented in the form of nonlinear state equations. They are the basis for formulating control laws. The parameters of linear slow- and full-active models were fine-tuned based on laboratory tests to the models of the discussed suspension structures. In the paper [5] I presented a nonlinear model of a serial structure. This model was used for the synthesis of the control law both in the paper [5] and in paper [6].[7] In the article [8] I applied the so-called Spencer's model known from the literature, a nonlinear model of a magnetorheological damper for the mathematical description of industrial heavy equipment seat. Similarly as previously, I wrote down the model in the form of state equations with a separated nonlinear part. In work [9], for the control synthesis I used the nonlinear model determined pursuant to an identification of the SMA (Shape Memory Alloy) spring parameters. I presented this model in the form of spectral transfer function. Quality indicators used to rating controlled suspensions The basic criterion for rating of vibration control efficiency is the vibration transmissibility ratio. Due to that the excitation amplitude and the amplitude of the sprung mass vibrations are the function of frequency. It is handy to make the value of the vibration transmissibility ratio also dependant on the frequency. Therefore to rating the vibration control one uses the vibration transmissibility function (it is frequency-dependant). It corresponds to the amplitude-frequency response, provided that the output signal from the object is a displacement (or acceleration) of the sprung mass while the input signal is the displacement (or acceleration) of the contractual point of contact between the tire and road surface. The displacement in time is caused by the vehicle movement on a rough road. An additional disturbance for the suspension are forces acting directly to the sprung mass related to a variable i.e. wind blasts, effect related to moving load, etc. The suspension quality rating based on the vibration transmissibility function course is ambiguous; therefore in my works I have proposed an aggregated quality factors. Strona 13 z 39

14 Summary of the habilitation thesis, Dr. Eng. Jarosław Konieczny Due to the nonlinear character of the tested suspensions, in order to determine the vibration transmissibility function one calculates the variances, of the displacement signals, based on an estimator determined by the formula (1) (1) where arithmetic mean of measurements. The values of vibration transmissibility function shall be determined pursuant to (2) ( ) (2) where: is an physical realization of a signal generated by vibration exciter The function is determined with the mono-harmonic excitation for frequencies within the scope of vibration reduction system. In the case of nonlinear system, this function depends on the excitation amplitude. To rating suspensions, one can also determine auxiliary characteristics illustrating the movement of the unsprung mass or the active part only. In this case, the output signal is the displacement of the unsprung mass while the input signal is the displacement resulting from road roughness or, in the case of rating an active part, it is the displacement of the sprung mass and the displacement of the unsprung mass. For linear systems the calculation of the value is reduced to determining the ratios of vibration transmissibility given in decibels (db) for various excitation frequencies. For the quality factor used to evaluate the driving comfort and the efficiency of vibration reduction system of the tested suspension I proposed the factor determined pursuant to the formula (3) ( ) (3) where: Fourier's transform of the output signal, Fourier's transform of the input signal. Frequency response (amplitude vs. frequency characteristics) of vibration reduction systems can be easily presented on the decibel scale. In connection with the said I proposed an aggregated quality factor in the form of the averaged vibration transmissibility function, expressed in decibels (3) (the Vibration Reduction Efficiency Indicator VREI). Then the indicator is also expressed in decibels. The mean is calculated within the range of the analysed frequencies from to. For the vibration reduction systems, the vibration transmissibility function chat should be under the X-axis (0 db) and should assume the smallest possible values. In the analysed cases of vehicle suspension systems, one should consider how the vibration caused by road roughness are transmitted onto the vibration of sprung mass. Strona 14 z 39

15 To evaluate the vibration transmissibility by construction element connections I used the coherence function. The coherence function between the output signal and the input signal has been defined by the formula (4) where: cross power spectral density,, power spectrum densities of the signals i. The function (4) is the frequency correlation coefficient between signals and. It rates the values from range [0, 1]. In the case when the value equals 0, signals and are independent of each other; this means lack of connection between construction elements. For the value equal 1, the output signal is a linear combination of input signal, which means a connection between construction elements. If the value of the coherence function is higher than zero but smaller than one, there is at least one of the following three cases: 1. the results of measurements are burdened with an error resulting from the presence of measurement noise, 2. the system combining with each other signals and is nonlinear, 3. the output signal is the result of influence of the input signal and other input signals not provided for. The assessment of the coherence function is obtained based on the determined estimates of power spectrum densities and the cross power spectrum densities. To assess efficiency of wheeled vehicle suspension, in work [5] I defined other quality factors. As mentioned above, the basic quality indicator used to assess vibration reduction efficiency is the vibration transmissibility ratio. This ratio, i.e. the quotient of displacements, considered in the frequency function is defined as the displacement transmissibility function. Due to the existence of nonlinear phenomena, in this article [5] I proposed the determination of this function based on the standard deviation (5) of the input and output signals, in compliance with the formula (6). (4), (5) where: response of the system (displacement of the sprung mass) to the monoharmonic input function,, standard deviation of the input and output signals. Defined by the formula (6), the function depends not only on the angular frequency but also on the amplitude of the excitation signal. In the case of a linear object, the proposed formula (6) boils down to determination the modulus of transmittance and does not depend on the amplitude. (6) Strona 15 z 39

16 Summary of the habilitation thesis, Dr. Eng. Jarosław Konieczny In order to assess the comfort and vibration isolation efficiency of vehicle suspension I used also the acceleration transmissibility function. For nonlinear systems, the function is determined as and defined by the equation (7) where:, standard deviation of the input velocity and output acceleration. An important problem in suspensions are dynamic interactions between the vehicle and the road and the wheel's maintaining contact with the surface (road holding). To assess these properties I used the criterion of (downforce) of the tire deflection defined by the formula (8) where: is the standard deviation of the wheel displacement signal in relation to the input displacement signal, absolute displacement of the excitation (input signal), wheel absolute displacement. Owing to this ratio one can assess the downforce of the wheel to the road surface. This is important for modern vehicle safety systems such as: ABS, ESP, EBD, etc., which require constant contact between the wheel and the surface. For evaluation quality of part of suspension without inclusion of the wheel dynamic properties, I used also the rattle space function defined by the formula (9). This function is the rattle space deviation measure where: is the standard deviation of the suspension displacement signal in relation to the wheel displacement signal, By analogy, just as in the case of displacement transmissibility function, definitions of the acceleration transmissibility function, tire deflection and rattle space, have been defined for nonlinear models of the vehicles suspension, (the formulae (7) - (9)). To compare the external energy demand of active elements I proposed an indicators specified by the following formulas (10) and (11) (7) (8) (9) (10) where: the instantaneous power charged by the active element from supplying system, transformed into the work and directed at vibration reduction system. Strona 16 z 39

17 This indicator is equal to the mean value of the instantaneous power delivered by the supplying system for the active element in the period of tests. The mean value of power is proportional to the work done by the active system in the period of the excitation signal. In the case in which the signal for the tested systems is the same, then based on the determined mean power one can make a comparison showing their demand for external energy (W= ). The tested system is understood to be a concrete structure controlled by a specific controller. The instantaneous power delivered from the hydraulic supplying unit is directly proportional to the value of the sprung mass. In order to compare the analysed active systems with regards to their energy, I introduced two additional ratios expressed in W/kg: the first one is related to the mean power - the power-to-weight ratio, and the latter, which is related to the maximum power. These ratios make it possible to compare the use of energy by active vibration reduction systems of various sprung masses. The quotient of the average power-to-weight ratio has been defined by the following formula (11) (11) where: the sprung mass. By analogy, I defined the maximum power-to-weight ratio. The synthesis of control laws for selected suspensions The PID controllers are the most frequently used controllers in industrial automation systems. In the case of control systems using these controllers, the results obtained are the basis for comparisons with other, more advanced control methods. However, in the process of control synthesis with the PID controller one cannot include the energy parameters, such as demand for external energy or the currently available power. In my works the said controller has been used for comparative purposes. One of the controller synthesis methods proposed by me, used for vibration control systems and presented in the papers of the monothematic cycle is the modal control approach. The modal control ensures both the required stability margin and the appropriate shaping of frequency characteristics. This method is a generalisation for the techniques based on the concept pursuant to which a system control can be achieved by means of controlling the systems' modes. One of the examples of this technique is the pole allocation method. For the MIMO systems the method boils down to the placement of a closed system's eigenvalues. The method of pole allocation enables choosing natural frequencies and the damping ratios. In the vibration reduction systems these are key parameters, therefore this method makes it possible to shape the amplitude versus frequency characteristics of a closed active vibration reduction system at the stage of its synthesis. In works [3,4] the control synthesis for the modal controller has been made owing the rules of choice of a closed vibration control systems eigenvalues, as defined by myself. I defined the rules governing the eigenvalues selection of the closed control system for active vehicle suspensions. Strona 17 z 39

18 The rules of eigenvalues selection for controlled vibration reduction systems. Eigenvalues of the system after the feedback loop closure should change the dynamic properties in such a way that the following conditions be fulfilled: The vibration transmissibility function should take the smallest possible values. For vehicle suspension these values should be below the 20 db line. Vibrations appearing as a result of dynamic effects, caused by road roughness and reduced tenfold ( 20 db) will have such a small amplitude that they could be reduced by, for example, the use of passive elements such as: sponge (seat), rubber vibro-isolators. The amplitude-frequency characteristics (for the suspension: vibration transmissibility) should be smooth, without any visible local gaining or reduction bands. The natural frequency of the closed system should be selected in such a way so as to omit the dominant frequencies of the excitation signal. The dominant natural frequency should be as low as possible (below 2 Hz) with simultaneous high damping. The damping ratio should be close to 1. In order to meet the above-specified conditions I have proposed a solution enabling the determination of system eigenvalues based on the selected amplitude-frequency characteristics. The method of control laws synthesis presented in papers [3,4] is a novelty for active vibration system reduction. It is based on the Bessel polynomials, which are frequently used in designing filters. Due to that from the Bessel polynomials one obtains the filter equation, i.e. a low-pass one, the beginning of amplitude-frequency characteristics will go along the line equal 0 db. For vibration reduction systems such properties, as for the lowpass filter, is admissible but only after lowering down it by for example 20 db. One can also take care to reduce vibration transmissibility in the pre-resonance band (of an open system) by correcting natural values. Therefore the method of Bessel polynomials is used only for the initial choice of the closed system poles while the final choice of their location depends on the knowledge of the object and the designer's experience. In order to determine the roots of a closed system characteristic equation I used the geometric dependencies (12) on a complex plane and I determined the roots of a characteristic equation based on the assumed damping ratios and natural frequencies : ( ) (12) Once the required roots of the characteristic equation are known, one determines the coefficients of the closed system characteristic polynomial to depending on (13) (13) The gains equation (14) for the modal controller should be determined based on the following (14) Strona 18 z 39

19 Vector elements are determined on the basis of characteristic equation coefficients of an open loop system to, a closed one to and the matrix. The matrix is a non-singular similarity transformation matrix, which transforms the state equations into the controllable canonical form. The other method proposed by me in works related to control of vibration is optimal control technique. In systems with optimal controllers the use of energy is taken into consideration by formulating an appropriate quality factor. This factor, apart from the state variables, takes into account the control signal. One could assume that the power delivered from an external power source is proportional to the power of the control signal. Choosing appropriately the weighting factors we get an indirect influence on the energy consumed by the active system. A synthesis of the optimal controller for the vibration control system is based on solving the optimisation problem for the object described by the differential equations. The most frequently used optimal controller is the linear controller with a quadratic quality cost function (LQR). The solutions of dynamic optimisation problem (LQ) have a number of valuable properties for the vibration control systems: The determined controls are accommodating due to opposing requirements the minimisation of output signal deviation from the desired path and a simultaneous minimisation of the 'input energy' delivered into the system. In the case of vibration control, the determined control laws take into consideration a compromise between opposing assessments for example the minimisation of the sprung mass acceleration, constant ground clearance, constant downforce of the wheel on the surface and a simultaneous minimisation of external energy consumption. The optimal control signal depends linearly from the state vector and therefore the control can be executed up to date in the feedback loop with only small requirements, if compared to the controllers computing power. The algorithms of solving the linear quadratic problem are fast convergent and low sensitive to rounding errors. This gives a possibility to adapt the controller gains to the object parameters in real time. In the case when the object model includes the suspension and road parameters, this feature can be used for the adapting the controller gains to the changing road parameters. The optimal controller can be executed in the analogue or digital technique for practically any number of: controlling variables, state variables or outputs. In modern control systems increasingly more frequently one can encounter the FPGA systems (Field Programmable Gate Array) co-operating with the FPAA (Field Programmable Analog Array) ones. The FPAA systems are based on CABs (Configurable Analog Blocks). Re-programmable analogue systems are used for continuous control systems. This technique makes it possible to omit the discretisation process in the control process. Due to the CAB structure, composed of operational amplifiers, analogue keys, resistors and capacitors with programmable values, one can fine-tune Strona 19 z 39

20 the optimum controller gains to the current disturbances band (i.e. changing road profile). In the vibration control systems with nonlinear executive elements one often uses linear approximation of their models for the synthesis of the control law. Owing to the minimisation of expressions dependent in the square form the control signal and state variables, one can ensure the correctness of linear approximation of the nonlinear system. In the case of the LQR controller at work [4] the minimised performance index has been written down by means of the equation (15) (15) The matrixes and have been taken by experimenting during my laboratory research, taking into consideration the compromise between effective vibration reduction and a minimal demand for external energy. The selection of weight matrixes provided for limitations related to the input range of the signal controlling the hydraulic servo-valve. The above-mentioned advantages result in that the application of optimum controller with a quadratic quality factor is justified for the execution of control in the analysed mechanical structures. Particularly important is the fact that in the synthesis of the controller one can take into consideration also the limitations of power of control signal while the state trajectory remains optimal. Nevertheless, in the process of its synthesis one cannot provide for a stability margin. In my papers the main control objective is the minimisation of output signal deviation (sprung mass displacement or acceleration) from the demanded path (in this case the desired value of ground clearance). A parallel objective is to obtain the desired vibration reduction with a minimum energy expenditure rate. In the paper [5] I conducted further research on the slow-active structure controlled by the LQ controller, with particular attention paid to indicators specified by the formulas (6) (9). Assessments of the suspension are made based on a number of frequently opposing indexes. For the needs of the of LQ controller synthesis I assumed the integral, quadratic performance index specified by the formula of (16) (16) It is determined as the weighted average of quality criteria corresponding to the indicators (6) (9) and the control signal energy (vibration transmissibility function (6), the acceleration transmissibility function (7), tire deflection function (8), the rattle space function (9), control signal energy). For the needs of the controller synthesis I assumed that the measure of energy consumed by the active system is the energy of the control signal. Limitations of the control signal scope is realised by the choice of weight. Strona 20 z 39

21 The controllers have been determined for various sets of weight values (16), corresponding to individual criteria of the suspension system. The method of control law synthesis used in this work [5] is based on a linear object model, therefore for the syntheses I also used the linear model. In the paper [6] the performance index for the LQ controller has also been defined as the weighted average of ratios corresponding to the selected criteria of the suspension system assessment. I treated the equilibrium point for the serial structure as the operating point. In this case, this point depends on the value of the sprung mass which can change, depending on the operator's mass, the load, etc. In particular, the value of differential pressure in the hydraulic cylinder chambers can change as well as the value of the signal controlling the servo-valve (at the equilibrium point). Pressure difference must compensate the sprung mass, i.e. the vehicle mass, the load or the operator. The servo-valve control signal is the sum of the signal determined from the LQ controller and the signal resulting from the operating point. In order to enable the compensation of this signal for various masses I determined analytically the (operating) equilibrium point for the discussed serial structure. Substituting for the performance index (16) the state variables assumed for the linear model, I obtained the performance index (17) ( ) (17) In my paper [8] to synthesise control I applied the optimal controller clipped to possibilities related to the actuator properties (clipped-lqr). More details concerning the vibration control system with a clipped-lqr controller have been presented in the part on laboratory tests of this elaboration. The results of laboratory tests of selected controlled suspension structures In order to assess the kinematic and energetic properties of the controlled dynamic structures I proposed a laboratory test methodology using a physical model of the discussed structure. The research technique presented in this monothematic cycle can be used also for the research on non-controlled vibration reduction systems. The research presented in my papers is based on subjecting the physical model of the analysed object to force or kinematic excitation. The applied excitations for a given object have a real nature or they occur purely for test reasons, i.e. random excitation with a set power spectrum density function, monoharmonic ones, etc. The assessment of the examined vibration control system occurs by comparing the defined quality factors determined based on signals: both experimental (obtained on the basis of research with the use of a physical model), and those obtained by means of numeric simulation of a mathematical model of the analysed object. For the execution of experimental tests on the considered vibration control system in accordance with the proposed method, one needs to develop measurement systems and control systems for the shaker giving the required excitation as well as for one for the tested vibration control systems. Due to the hardware structure and the software Strona 21 z 39

22 architecture applied, the control and measurement tasks differ with regards to the organisation of measurement data. A set of measurement data for the analysis of the discussed object dynamics includes a couple or to over a dozen measurement channels and the signals for parameter identification require low sampling time. In order to optimise the speed of big data volumes' transmission between the measurement system and the CPU I used such a transmission, which provides for collecting data in blocks. On the other hand, for the control tasks with deterministic sampling time, the measurement and generation of output signals must be executed point by point, with consideration to the time necessary for the execution of control algorithm. Below is my definition of six sentences selected for execution by the control and measurement system of the vibration control system in separate programme threads. The tasks to be implemented by the control and measurement system of the system of vibration control: Basic tasks: Real time control (control tasks with strictly defined time dependencies between hardware input and output), Data measurement and acquisition (various signal processing times, various kinds of input). Additional tasks: Signal processing, Monitoring various variables important for a selected process, Communication with external devices, Computing and generating the set value for kinematic and force excitation. The above-specified tasks have different priority, execution time and computing complexity. Some of them must be executed on a cyclical bases with strict execution time, in other cases the time can vary and it is not a critical parameter. Taking into consideration the above-specified requirements, tasks were divided into groups with identical priorities and cycle execution time. Owing to such an approach, individual tasks have been placed on hardware platforms most suitable for their type, priority or execution time. Moreover, the division of tasks into groups enabled their execution in separate software (threads) loops with appropriately selected cycle execution time. I used the FPGA system, a computer with real time controller and a PC playing the role of a virtual control panel as my computing platforms. The FPGA system executes the following tasks: the critical and fastest with regards to the execution time and those related to security. Owing to the FPGA use, the algorithms are hardware-executed. Such solutions are characterised by high reliability and operations speed of the control system. A disadvantage of this solution are its limitations due to the complexity of the algorithms executed and those related to the available data types (i.e. Boolean, integer, fixed-point type). Limited hardware resources of the FPGA system do not make it possible to Strona 22 z 39

23 implement: more advanced control algorithms, signal processing or generating the excitation signals. In order to execute the more advanced tasks, which require operations on signals represented by floating-point variables, I proposed a controller working with a real time operating system. An advantage of this solution is that one can execute very complex algorithms requiring high computational power; nevertheless there is a risk that the operational system will delay the control process as it executes other tasks, i.e. serves other threads. For this reason the basic task of this system is to acquire measurement data with the application of hardware buffer and the use of many modules differing with respect to the hardware. In the case one uses more than one measurement module (types of hardware input) there is a need to synchronise those with the trigger system use. An additional functionality of the designed system is the experiment planning module. To control the excitation generator (vibration shaker), set the excitation parameters, observe the shaker parameters and reaction to emergency stop function, graphic user interface is to be used. This interface is implemented on a PC or other virtual panels located on various hardware platforms communicating with each other. In the course of laboratory research presented in my papers [3 7] I measured the displacement and acceleration signals of the sprung and unsprung mass as well as the excitation signal for systems controlled with various controller types. Apart from the abovementioned quantities, I registered also the remaining signals complementing the state vectors and, additionally, the acceleration of the discussed structure's mass. Moreover, in order to compare energy dependencies of the tested systems I calculated the instantaneous power taken from the supplying source based on the measurements of the supplying pressure and the flow intensity of working fluid between the feeding system and the active element. The registered signals of the displacement allows us to determine of frequency responses. On this basis I calculated the functions of vibration transmissibility from the input disturbance to the output that is the displacement of sprung mass. My research on controlled vibration reduction systems has demonstrated that the vibration reduction efficiency, and therefore the efficiency of the applied control law, to a great extent depends on the energy used by the active element. This energy depends on the disturbance type, yet it is also the function of the control law adopted. In the controler synthesis some techniques to a smaller or greater extent enable the control of energy use by an active element (actuator). In order to assess the energy demand I proposed energetic indicators for active suspension assessment. This assessment is made based on the registered time series of the instantaneous power charged by the active element from an external power source. Additionally, I determined the average power taken from the power source by the active unit. In my work [4] I compared the laboratory test results for various active vehicle suspension structures controlled by modal and optimal controllers. This comparison refers both to the vibration transmissibility function and the time course of instantaneous power Strona 23 z 39

24 (with the identical input function for both structures). In this paper, for an easier comparative assessment I determined also the aggregated quality indicators (3), (10) and (11). In order to determine the efficiency of the serial structure for opposing indicators, in the article [5] I determined controllers by solving the optimisation problem for the performance index specified by the formula (17). Suspension quality evaluation has been made in the course of laboratory tests of the sprung systems, with controllers determined for various weighting factors sets. For every system I determined the vibration and acceleration transmissibility functions and time courses of the instantaneous power taken from an external power source. I have also made an analysis of such assessment criteria for vehicle suspension, such as the rattle space function or the tire deflection one. In order to determine these functions, vibration reduction systems have been excited by a sinusoidal disturbances with frequency increasing in a linear way. My share in work execution [5] was as follows: formulating efficiency assessment indicators for the vibration reduction systems, contribution to modelling the applied slowactive suspension type, constructing a physical model of the tested structure, synthesis of the control laws, laboratory tests, implementation of the applied control laws on the real time controller and preparing as well as analysing the results obtained. In the next paper [6] belonging to the monothematic publication cycle, I considered the problem of optimal controller synthesis for objects disturbed by sinusoidal signals with an infinity horizon time. To assess the control law I proposed a modified averaged quadratic performance index with infinity horizon time. It is based on the proposed control signal distribution method, in the range between zero and infinity on the sum of sinusoidal components with selected frequencies and an additional auxiliary signal. These frequencies correspond to external frequencies of the sinusoidal excitation. This performance index has been formulated in such a way that every sinusoidal component corresponds to a separate weight matrix. Owing to this I obtained a possibility to differentiate between energy restriction imposed on the control signals, depending on the frequencies. Due to the fact that such distribution is not always possible a class of control signals for which it is correctly determined has been characterised. The proposed performance index has been used to formulate the optimisation problem with an infinity horizon time for linear systems with sinusoidal excitation. I determined the optimal solution for the given optimisation problem. I selected the optimal control in such a way that it is not dependant on the state vector or initial conditions, but it depends only on the excitation signal vector. I have developed an original method for synthesis of control system with a modified performance index. In order to verify the presented considerations I conducted a synthesis of controller for the serial structure of vehicle suspension. I presented the results of numerical simulation and laboratory tests of the active vehicle suspension designed. An important disadvantage of the majority of known active vibration reduction systems is their high energy demands, which in many cases is the barrier to their wider use. For this reason I designed such a system, in which part of vibration energy is regenerated Strona 24 z 39

25 and, instead of being turned into heat, it is stored for further use. This suspension system, owing to its hybrid construction, ensures smaller consumption of external energy which has to be fed into the system in order to obtain an effective vibration reduction. Based on my experience gained in the framework of a research project, I designed and executed an active suspension whose main supply source is a specially designed hydraulic power supply driven with the energy of the vibrating mass, for which high vibration isolation efficiency is not necessary. Energy shortages are compensated from an independent, separate supplying source. For this purpose I designed and executed an energy management system. In scientific literature there is no information concerning dependencies between the regenerated energy and the one necessary for an independent active control, in particular in the aspect of excitation with the same frequency spectrum character. In mechanical regeneration systems for vibrating systems there is a very important impact of the amplitude and the excitation frequency values on the amount of energy harvested. Of similar importance are the excitations types in controlled vibration reduction systems, in particular in the context of optimisation algorithm. In world solutions one can most encounter primarily works related to the electro-dynamic and piezoelectric systems for energy harvesting from vibrating systems. These systems are used for small amplitude and high frequency vibrations. In the article [7] I presented a system of controlled suspension ensuring effective energy harvesting from vibrating systems and storing it in hydraulic accumulators. This energy, together with the energy from other power sources, is used to supply the actuator of the active part of suspension. The work [7] has been made in the framework of a research project called 'Electro-hydraulic systems for active reduction of vibration using the energy of unsprung mass' (no 5 T07C ), for which I was the originator and the lead contractor. The research on systems with energy regeneration have been conducted for years and the leading research trends include systems with electro-dynamic and piezoelectric actuators. In the discussed work I used electro-hydraulic actuators: both for active mechanical vibration reduction and in order to regenerate energy. Research conducted by me has demonstrated that excitation frequencies higher than the dominant resonance frequencies lead to a more effective charging of the storage system. This is caused by a higher phase delay between the excitation and the unsprung mass displacement. High phase delay (close to 180 ) leads to increasing the relative displacement. In the course of experimental tests I used this property and I used, as the excitation, the philharmonic signal composed of two dominant frequencies. The control objective was to reduce vibration amplitude. The vibration amplitude of the first (dominant) harmonic is reduced by the active element, on the other hand vibrations with higher frequencies are reduced by means of transforming the sprung mass energy, which in classic systems is transformed into heat. Based on the results of lab stand tests and the mathematical model simulation I determined an effective actuator operation band. The amount of energy accumulated in the storage system depends on a number of factors. For the tested suspension system the most important of them are the following: Strona 25 z 39

26 the sprung mass to unsprung mass ratio, energy demand for the active suspension system (this parameter is related to the mass and the required frequency band, for which the vibration reduction is achieved), the type of the excitation signal, in particular the vibration amplitude for frequencies higher than the resonance frequencies. In recent years scientists have elaborated a number of actuator concepts, which could be used as the active elements for vibration control systems. These actuators are mainly: magnetorheological dampers, springs using the super-elasticity effect (SMA springs) or actuators based on piezoelectric materials. Such elements, often referred to as smart, apart from their many advantages, have also other features which must be provided for in the control law synthesis. Mathematic models used for the description of smart materials are usually nonlinear. This nonlinear peculiarity is usually related to the hysteresis effect. In my works I decided to take advantage of these elements. This, however, results in a need to take into consideration also the nonlinear peculiarities during the control law synthesis. The work [8] belonging to the cycle refers to controlling the driver's seat suspension by means of a magnetorheological damper. In this article I used the modified clipped LQR method to control the nonlinear semi-active element with hysteresis. Smart materials are increasing more frequently used in semi-active vibration reduction systems. As mentioned before, omitting the nonlinear dependencies in a mathematical description could lead to a less effective control and, as a result, poor quality of the vibration reduction control system. It is therefore important to take into consideration those disadvantageous phenomena related to actuator at the stage of the controller's synthesis. The method I proposed in my work [8] to determine the control law for semiactive vibration isolation systems is the clipped-lqr method. It enables the use of the LQR control to limited possibilities of the active element, for example the controlled viscous damper. Dampers can only dissipate energy in a vibration reduction system. With the help of these elements we cannot supply energy into the system, to be used to generate forces transformed into the work of the controlled element. The energy is supplied to the system solely to change the parameters of vibration reduction system, i.e. the damping ratio. Energy in this scope (the 1st and 3rd quarter of the coordinate system of the damper characteristics) is turned into heat. Therefore control by means of the LQR controller must be limited - clipped to - the scope of possible control only, therefore the force direction of the reaction contrary to the direction of the relative damper velocity. The efficiency of vibration reduction with the use of the clipped-lqr controller is limited by the actuator. Nevertheless, in cases in which the consumption of external energy cannot be too high, and there is a need to control of vibrations, there is the possibility to use the optimal control law in the clipped scope. In the discussed article [8] I proposed a modification of this method so as to make it possible to provide for the hysteresis and other nonlinear properties of the actuator in the synthesis of the control law. The modification was based on choosing an optimal weighting factor for the controlling signal, for the given suspension system, one that takes into consideration: nonlinearity, its parameters and the excitation character. Strona 26 z 39

27 Verification of this drafted method was made by determining a controller for the semi-active suspension of the operator's seat of an industrial vehicle machine. The semi-active suspension system controlled by the proposed clipped-lqr controller has demonstrated better efficiency in vibration reduction compared to a passive system in the whole range of analysed frequencies. In the article [9] I proposed the use of springs made of an alloy with shape memory (SMA) to formulate the dynamic characteristics of a resonance vibration screen. These springs change their stiffness as a result of their temperature change, therefore in real time one can control the resonance frequency of the screen. In this article I formulated a mathematical description of the controlled SMA spring and identified its parameters. The model takes into consideration both the phenomenon of spring stiffness changes and the damping, depending on the alloy temperature and the frequency of spring vibrations. I have conducted experimental tests on the designed spring and the physical model of the screen and published some selected characteristics. For the analysed system a control law has been formulated. I have conducted numerical simulation and laboratory research of the vibration screen model in a closed and open loop system. The research has demonstrated that the designed control system compensates for the changes of the vibrating mass even by ±30%. The basic part of the article [10] concerns the assessment method of the technical condition of the support structures connection to its foundation. The proposed method includes an analysis of acceleration measurements results for the elements connecting the foundation with the support of the cableway. The assessment of connection is made on the basis of ratios proposed and used in the monothematic publication cycle. In the second part of this paper [10] I have presented analysis results of the tested supports from before and after the overhaul. Long-term use of cableway supports and other slender constructions with variable loads and strongly diverse weather conditions can cause the following: the appearance of defects in the ferrocement foundation, corrosion of the steel construction or loosening the fixing elements. Periodic inspection are aimed to detect such defects and prevent dangerous exploitation. A big problem in the defect detection is lack of access to the tested elements and difficulty with visual assessment of the support and foundation connection. Tests described in the article [10] refer to a complex composed of three sections of a cableway with 62 supports, which has been in operation for 40 years in the Silesian Culture and Recreation Park. Further operation of the cableway required an assessment of, among others, the technical state of foundation supports. The visual assessment of the state has demonstrated significant wear by corrosion of the supports as well as damages to the external layer of the ferrocement foundations. In order to choose the damaged supports for overhaul I proposed a method based on acceleration measurement. The acceleration of every foundation and support was measured at the same time, with maximum load of cableway at nominal speed. During the tests the acceleration signals in selected points of the supports and foundations were registered with special measuring and data acquisition devices. In the situation of a correct, i.e. stiff Strona 27 z 39

28 connection of the foundation and the support, the time course of acceleration should be compliant, both with respect to the amplitude and phase. In the case of loosening in their connection, the amplitude of the support's acceleration is higher than the amplitude of the foundation's acceleration and, additionally, there is no compliance between the acceleration phases. Loosening a given connection has also been seen in the power spectral density characteristics of the measures signals. If the discrepancy between these characteristics is too big, it could mean the occurrence of loosening in that connection. The characteristics of power spectral density makes it also possible to assess the technical state of the connection in specified frequency bands. The time and amplitude vs. frequency characteristics presented in the paper do not give the quantitative assessment, which can be used after the application of the coherence function. In paper [10] I analysed the time and frequency characteristics of the foundation and support acceleration for a number of supports and for a selected support prior to and after the overhaul. The proposed method of diagnosing cableway supports by means of the coherence function in the resonance frequency bands enables a quick, cheap, non-destructive and effective assessment of the technical state of a connection between the steel support and its foundations. This method was successful in practical use and was positively evaluated by the Transportation Technical Supervision (the body responsible for the supervision of transportation means in Poland) The applicant's individual contribution to the development of scientific discipline and contribution in percentage Below you can find the applicant's individual contribution into the development of the scientific discipline, as found in individual items of the presented publication cycle and contribution to their drafting, in percentage: In article [1]. Designing a model of controlled hydraulic damper based on a dimensionless damping ratio, determined from energetic phenomena. Laboratory tests of a hydraulic damper controlled by a servo-valve. My contribution, in percentage, to the preparation of this article [1] is 80%. In articles [1,2]. Designing actuator models designed for vibration control systems and their laboratory verification. In articles [2,4]. Formulating a nonlinear hydraulic model of an active actuator enabling the modelling of entire suspension units. Preparing the method of model linearization at the discontinuity of the first derivative along the admissible system trajectory (with consideration of real signals) for the purposes of control law synthesis. Defining the energy indycators for the assessment of vibration control systems. My contribution, in percentage, to the preparation of the article [2] is 100%. In article [3]. Strona 28 z 39

29 Determination of the influence of power deficit on the stability and dynamic properties of the full-active type of suspension, controlled by selected controllers. My contribution, in percentage, to the preparation of this article [3] is 100%. In articles [3,4]. Synthesis of active vibration control systems for selected kinematic structures. In article [4]. Conducting laboratory tests on suspension systems with various kinematic structures and comparing their dynamic and energetic properties. Experimental comparison of kinematic slow-active and full-active structures, fit to be used in wheeled vehicles, controlled by controllers determined with the use of the same methods. Preparing models of controlled vehicle suspension with consideration to nonlinear properties of the electro-hydraulic flow servo-valve. My contribution, in percentage, to the preparation of this article [4] is 65%. In article [5]. Drafting the control law providing for nonlinearity effects of the slow-active type of suspension at operating point, depending on the value of the sprung mass. Formulating efficiency assessment indicators for the vibration reduction system and - on the basis of the said - formulating the performance index necessary for the synthesis of control law providing for opposing components. Modelling the applied kinematic structure. My contribution, in percentage, to the preparation of this article [5] is 30%. In article [6]. Co-participation in drafting a new optimal control law for systems with sinusoidal disturbance the WMOC, weighted multitone optimal controller. The implementation of the WMOC controller for the serial structure and conducting laboratory tests and assessment of that structure based on the proposed performance indexes. My contribution, in percentage, to the preparation of this article [6] is 25%. In article [7]. Designing the structures, constructing it and laboratory tests of regenerative suspension. Synthesis of control law for the hybrid vibration reduction system with energy harvesting. My contribution in percentage to the preparation of this article[7] is 75%. In article [8]. Drafting modified method of clipped-lqr for a semi-active suspension of the driver's seat. My contribution, in percentage, to the preparation of this article [8] is 40%. In article [9]. Implementation of the SMA spring control algorithm on the FPGA controller and determining efficiency indexes for the operations of a vibration screen. My contribution in percentage to the preparation of article [9] is 25%. In article [10]. Drafting methods of assessing the technical state of foundations based on vibration signals. This method has been tested on the example of foundations of cableway supports in the Strona 29 z 39

30 Silesian Culture and Recreation Park. My contribution, in percentage, to the preparation of the article [10] is 85%. My percentage contribution to the presented monothematic publication cycle on average amounts to 62.5%. Summary All works making up the above-presented monothematic publication cycle have been published in renowned scientific publications closely related to the presented topic. The achievement which constitutes the basis to open the habilitation procedure, presented as the monothematic publications cycle entitled: 'Analysis and synthesis of vibration control systems with emphasis of energetic parameters' is the result of works conducted after obtaining the Dr. Eng., and it is in fact a detailed analysis of selected active structures of vehicle suspensions: from the modelling stage, through control synthesis, construction of physical models to laboratory tests. In these papers I pay special attention to the demand for external energy necessary to obtain the assumed level of vibration reduction. The scientific research conducted and presented in the published papers present my contribution to this, here discussed, scientific disciplines and includes: an original laboratory test methodology, taking advantage of physical models taking into account dynamic similarity to real objects and the techniques of fast prototyping of control systems, the author's own quality indicators providing for energy parameters of active vehicle suspension, achievement of compromise for opposing quality indicators, owing to the applied optimal and modal control methods, designing and executing an active suspension whose main source of power supply is a special power supply driven by the energy harvested from vibrating system as well as designing and executing energy management system for such the said system, limiting the demand for external energy for active vibration control systems owing to the proposed control techniques, practical execution of the proposed techniques and their verification by tests, the application of smart executive elements as actuators for the vibration control systems. These achievements result in a significant development of the science area Automation and Robotics both in Poland and in the whole world. 5. Other scientific and research achievements Author and co-author of scientific publications The list of my publications includes 81 scientific works, herein 61 titles after my doctoral thesis. Almost all (except for two) refer to the control of vibrations of dynamic structures or their monitoring and assessment. Journals in which these articles have been Strona 30 z 39

31 published are closely related to the topic of the specified scientific achievement (Table 3). In recent years I focused on the publication of my achievements in important, well-known periodicals whose topics are related to vibration control techniques. The result of the said was the publication of papers in journals listed on the Journal Citation Reports (JCR) base, the so-called Philadelphia list (indexes in Table 2). The other 21 titles are articles published in foreign or domestic journals available also abroad. These are the following journals: listed on the score list of the Polish Ministry of Science and Higher Education, part B, foreign periodicals or Polish periodicals published under the aegis of the Polish Academy of Science: o Solid State Phenomena (5), o Archives of Control Sciences, o Engineering Transactions (2), o Archive of Mechanical Engineering, o Journal of KONES, well-known specialist publications, such as: o Measurements, Automation, Control (Pomiary, Automatyka, Kontrola) (2), o Hydraulics and Pneumatics (Hydraulika i Pneumatyka), o Pneumatics (Pneumatyka), o Drives and Control (Napędy i Sterowanie) (2), Scientific Brochures of prestigious Polish technical universities (5). Additionally, 6 works are chapters in monographs, of which five are international monographs and one is a monograph from the scope of electric metrology. Participation in thematic conferences 36 of my works are articles - lectures presented during conferences, including 33 international conferences. In years 1999, 2002, 2009 I presented my works during world largest conference on the topic of active vibration control methods, the 'ACTIVE International Symposium on Active Control of Sound and Vibration'. In 2005 I presented my paper related to modal control of vehicle suspension at the 'Internoise' Congress, the International Congress and Exposition on Noise Control Engineering. That Congress is devoted to the topic of vibration and noise control. In years I presented 13 works during the international 'MARDiH' conference, the Conference on Active Noise and Vibration Control Methods. That conference is one combining science with industry and organised in a two-years cycle by my own Faculty. In years I presented 8 works in the area of control during the ICCC, the International Carpathian Control Conference. This conference gathers control experts mainly from the Carpathian mountains countries, but also guests from other regions of the world. Four works related to the application of smart materials for vibration reduction were presented during the MSM Mechatronic Systems and Materials conferences in years I presented twice my papers during the XLVII and XLIX Simposium 'Modelling in Mechanics', whose outcome were my publications in Strona 31 z 39

32 journals under the aegis of the Polish Academy of Science. The remaining works have been presented during the International Scientific Conference of FME in 2000, the International Scientific and Technical Conference and the 'PRMR' Robotic Machine Development Problems. Patents I am co-author of five patent dossiers, awarded and published in the Patent Office Bulletin. Four of them are related to controlled suspensions or their actuators dedicated for the controlled suspension. The most important patents awarded are the following: Suspension system of the road vehicles (PL B1). Suspension of motor vehicles, especially multi wheel off road vehicles (PL B1). Additionally, one more patent have been submitted and registered in the Patent Office of the Republic of Poland. The next patent referring to active absorber of vibration caused by sea waves is currently awaiting the approval of the United States Patent and Trademark Office (No /PV). An application for patent protection submitted under the title 'High- Load, Fast Reaction Active Heave Compensator (AHC) Technology and System' refers to the compensation of vibrations by an object lowered near the bottom of the ocean on a long steel cable from a platform subject to vibrations due to sea waves. Contribution to scientific research projects execution In years I took an active part in 15 research projects as a contractor. The majority of these projects related to vibration control systems. They were implemented mainly in cooperation with the Dynamic and Control of Structures Laboratory which I am the manager. In my scientific activities I pay special attention to the practical execution of techniques tested in laboratories and described in scientific publications. The outcome are my contacts with industrial centres, my participation in scientific and industrial consortia as well as seven applications submitted according to the new formula to the National Centre of Research and Development in the framework of projects PBS 2 and PBS 3. The result of these applications is a project of which I am the manager - recommended for funding under the Applied Research Programme. This project is entitled "Active Suspensions of High Mobility Multi-Purpose Wheeled Vehicle" and is closely related to the subject of a monothematic cycle of publications. The projects, for which I am the originator, and which are very important with a view to the topic of the application are: [1p] Active suspension strut of a wheeled vehicles, , contractor. [2p] Autonomous universal tracked platform, for combat logistics tasks according to the standards of the modern battlefield APG, 0R , , contractor. [3p] Self-excited acoustic system (SAS) for the monitoring of stress changes in elastic constructions and rocks, N , , contractor. [4p] Active, regenerative vibration reduction system using electromagnetic actuators, N /2981, contractor. Strona 32 z 39

33 [5p] Laboratory tests, modelling and control of mechanical systems based on shape memory alloys, 4 T07A 04129, , contractor. [6p] Mechanical vibrations reduction systems for multi-dimensional dynamic structures 4 T07A , , contractor. [7p] Active vehicle suspension with limited energy consumption, 4 T07C , contractor - doctoral grant. [8p] Electrohydraulic systems of active mechanical vibration reduction using energy harvested from unsprung mass, research project no 5 T07C financed by the Polish Committee for Scientific Research (KBN) ( ), contractor. [9p] Active vibration control systems of mechanical structures with variable parameters disturbed by random excitation, 7 T07C , ( ), contractor. Participation in contracts with industrial centres My laboratory research, focused on the practical execution of the analysed techniques, have resulted in works executed for Polish industrial centres. In years I took part in 14 contracts executed by the AGH University of Mining and Metallurgy for industrial centres. These works to a great extent referred to the implementation of measurement or diagnostic in mechanical systems. List of contracts for industry in which I was a contractor: [1u] Assessment of the technical state of elements and units of the Nosal single line cableway, based on the performed tests. Work executed for the STRAMA Transportation Company, contract number , Cracow, December [2u] Examination of the ELKA chairlift supports and technical expertise of the support feet and their anchorage. Work for the Silesian Culture and Recreation Park in Chorzow, contract no Cracow, June [3u] Examinations of the Strugi-Szczawiny chairlift units in Korbielow. Work for Tourism Agency in Gliwice, contract no Cracow, July [4u] Examining the Piękna Góra chairlift with analysis of results. Work executed for the 'Piękna Góra' Sports and Recreation Centre in Goldap, contract no Cracow, December [5u] Examinations of the support constructions for supports along the I and II segments of the ELKA cableway. Work for the Silesian Culture and Recreation Park in Chorzow, contract no Cracow, January [6u] Measurements of real drive load of the 'Szyndzielnia' chairlift and analysis of results obtained. Work for ZIAD Bielsko-Biała S.A., contract number Cracow, October [7u] Examinations of drive for connection units and the support constructions of the cableway Strugi Szczawiny at Korbielow. Work executed for MOSTOSTAL Zabrze ZMP 'Czechowice', contract no Cracow, November [8u] Final commissioning examinations of Dzikowiec chairlift according to the author's own programme. Work executed for MOSTOSTAL Zabrze ZMP 'Czechowice', contract no Cracow, November Strona 33 z 39

34 [9u] Optimisation of the drive system's operation in the cablelift to Góra Żar in Międzybrodzie Zywieckie. Work executed for MOSTOSTAL Zabrze ZMP 'Czechowice. [10u] Laboratory and model examinations of operator's seat produced by the STER company. Innovation and Implementation company, Grzegorz Jaśniewicz Poznań, Wichrowe Wzgórze (2011), contractor [11u] Development of shock absorption system for machines and vehicles' operator seats. Innovation and Implementation company, Grzegorz Jaśniewicz Poznań, Wichrowe Wzgórze 10/62. (2010), contractor. [12u] Special examinations of a separate unit (roller, cable drive) of the lift machine working in the R-II mineshaft, section of S O/ ZG Rudna, according to the approved 'Programme of tests and examinations' commissioned by ABB Sp. z o. o. ul. Żeglańska 1, Warszawa [13u] Analysis and assessment of examination results and the parameters of mineshaft machines in the R-II O/ ZG Rudna pit, in test operations in order to obtain permanent machine operational permit, commissioned by ABB Sp. z o. o. ul. Żeglańska 1, Warszawa [14u] Modernisation of the diagnostic stand for tests on hydraulic drills (Jackhammers) by KGHM Polska Miedź S.A. (2012). The execution of these works gave me precious experience and directed my research at the practical use and application of my theoretical knowledge onto real objects. Foreign internships I took part in the following foreign internships: Finland, VTT Research Centre in Oulu, 2013 study visit in the framework of the project 'Scientists Closer to Industry' organised by the Industrial Research Institute for Automation and Measurements financed by the EU from the National Cohesion Strategy, Human Capital programme. VTT is the largest research organisation in Northern Europe. Ukraine, Scientific and Research Centre of the Khmelnitsky National University, Canada, Ecole Polytechnique de Montreal, 2009, Canada, Laval Université, 2009, United Kingdom, University of Southampton, ISVR 2002 Didactic activities In the framework of my teaching activities I supervise the teaching of two courses: Parts of Industrial Automation of the 1st degree in the field of study Automatics Control and Robotics, Measurement Systems of the 2nd degree in the field of Automatics Control and Robotics. For these courses I am a lecturer. Additionally, in the framework of the module of Automatic Control Basic of the 1st degree in the field of study Mechanical Engineering I give some lectures relating to Parts of Industrial Automatics. Strona 34 z 39

35 I also run laboratory exercises for the following subjects: Signal Analysis and System Identification of the 1st degree in the field of study Automatics Control and Robotics and the Measurement Systems of the 2nd degree in the following specialisations: Automatics Control and Measurement Systems, Robotics, Automatics in Mining Machine Systems). For all courses that I run I prepared the teaching curricula. Apart from the above-mentioned subjects, in my career I also taught the following courses: Automatic Control Basic auditorium exercises, Automation of Technological Processes a seminar, Metrology laboratory, Parts of Industrial Automatics auditorium exercises, Parts of Industrial Automatics laboratory, Exploitations of cable transportation devices lecture, Exploitations of cable transportation devices laboratory, Industrial Control and Measurement Systems laboratory, Dynamic and control of structures laboratory, Identification of Technological Processes laboratory. The diploma thesis for which I was the lead professor, both at the bachelor and master degrees, refer mainly to the topic of vibration control and measurement systems. There of the students for whom I was the lead professor are now doing their doctoral studies, a fourth one is a scientific employee in a research institute and another one was awarded the title of D.Eng. Organisational activities I am the manager of two laboratories: didactic the Measurement Systems Laboratory, research Dynamics and Control of Structures Laboratory. The Measurement Systems Laboratory established in 2000 is currently the busiest Laboratory belonging to the Department of Process Control. Classes taught there six include subjects for the specialisations of Automatics Control and Robotics as well as Mechanical Engineering in the Faculty of Mechanical Engineering and Robotics. The topics of classes relate mainly to the measurement techniques, signal analysis and processing as well as advanced control systems. Under my management of the Laboratory of Dynamic and Control of Structures, specialist stands were added: one for quarter models of vehicle suspension tests and one for vibration reduction system tests. I have been the originator of these two test rigs and the author of their projects as well as the contractor of the measurement and control system. These stands are based on electro-hydraulic high power exciters, able to generate harmonic vibrations with: strictly defined shape, frequency, amplitude or random ones, with a pre-set probability density function and power spectrum density. This Laboratory plays the role of research facilities for the Department of Process Control. Since it has been established in 2001, there have been 8 Doctoral Thesis completed and three more Strona 35 z 39

36 are now in preparation. In the said laboratory there were also 13 research projects completed, financed by bodies such as the KBN, MNiSW, NCN. I am a member of the Organisational Committee and secretary of the International MARDiH conference, Active Noise and Vibration Control Methods, which takes place every two years. I am responsible for the process of article evaluation, presented and published in the framework of the conference. Moreover, I was a member of organising committees of the following Scientific Conferences: APRO The Automation of Machines, Devices and Processes as well as cyclic ICCC conference, the International Carpathian Control Conference. I take an active part in the operations of the Statutory Department Activities, which results in my participation in drafting reports on its activities in years Editor and reviewer in scientific journals I was the co-editor of three issues of the Journal of Low Frequency Noise, Vibration and Active Control quarterly, published by the University of Sheffield, UK. I am a reviewer for the following Journals: Journal of Dynamic Systems, Measurement, and Control, published by ASME, Ain Shams Engineering Journal published by Elsevier. These publications are listed in the JCR base. Quotation indexes In table 1 I presented the basic quotation indexes referring to my papers, given in accordance with the most popular scientific publication bases. Table 1. Statistics and quotation indexes Web of Science Scopus Google Scholar, Publish or Perish H index Number of documents in the base 14+5* Number of times citation * including patents In table 2 I presented indexes for journals, in which I published my papers. This Table is an excerpt from the JCR base. The total, 5-year Impact Factor for the 61 papers which have been published after I was awarded the doctor title is The total number of points scored according to the Ministry of Science and Higher Education pursuant to the list of publication year, without dividing scores among co-authors is 347. The topics of my papers published in periodicals from the IF - to be found in the WOS base has been presented in table 3. Strona 36 z 39

37 Table 2. Indexes concerning journals which published my papers Table 3. Topics discussed by Web of Science categories Strona 37 z 39

38 Tables 4 and 5 show a report from the Google Scholar base (identified also as 'Publish or Perish') and Web of Science, which constitute a part of report summarising the works of which I have been the author or co-author. These are the most important report excerpts. Table 4. Citation rapport given by Google Scholar Table 5. Citation rapport given by Web of Science Strona 38 z 39