Chapter 1. Introduction. Relationship fields in mechatronics.

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1 Chapter Introduction. Mechatronics The creators of curricula at technical universities have known for a long time that a good designer, apart from the skills of coding, should possess interdisciplinary knowledge. In addition to teaching mechanics, strength of materials, basics of construction and mechanical technology, many mechanical engineering faculties conducted classes in electrical engineering, electronics, automation, hydraulics and pneumatics, information technology, measuring instruments, machinery architecture, and other. The engineer educated according to this curriculum is expected to have broad knowledge and can choose the appropriate solution directly using known techniques or the knowledge of experts he had known. In 969, a concept name mechatronics was invented in Japan (and later distributed in the 7s) to determine the synergistic use of knowledge of the basic fields of technology. The word results from a combination of words mechanics and electronics. Authors [Xie (23)] and [Lerner and Trigg (25)] give definitions and descriptions of significance supplemented with graphs presenting the concept of mechatronics. Figure. exhibits one of the patterns showing the relationship between modern fields of technology which is presently observed in mechatronics. electrotechnics electronics mechanics MECHATRONICS informatics automatics control computer engineering fluid engineering Fig.. Relationship fields in mechatronics. One of the greatest challenges in the development of mechatronic devices and systems are, next to their variety, also progressive complexity and versatility [Scherz and Monk (23); Budynas and Nisbett (25); Cetinkunt (27)]. The progress of

2 2 DYNAMICS OF MECHATRONIC SYSTEMS civilization enforces researchers and engineers to search for non-coexisting solutions in various fields of science and technology [Karnopp et al. (22); Di Paola and Cicirelli (2)]. Noticeable lack of sufficiently well developed methods of dynamics analysis supporting interdisciplinary aspects of processes of the development of mechatronic devices and systems enhances the willingness to use an optimization theory and different techniques of numerical modeling. The numerical simulation and some related processing with measurement signals are highly correlated with advanced optimization methods. In this context, the device and system models presented in this monograph gain in importance and for many engineers should be an interesting source of information about mathematical modeling of dynamical systems, numerical experiments, experimental measurement, and various optimization problems of mechatronics..2 Systems System (gr. systema complex object) a physical or abstract object in which reciprocal links can be distinguished. According to one of the criteria [Schmid (22)], systems can be divided into: abstract and physical, static and dynamic, open and closed, autonomous and nonautonomous, etc. System an assembly of reciprocally incorporated elements fulfilling a specific function and being treated as separated from the environment for a specific purpose, i.e., descriptive, exploratory and other. For example, a technological process defines a system. The concept of a system is used practically in all areas of human life and refers to either phenomena, objects or processes in nature as well as those created by people. z(t) - disturbances x (t) y (t) input signals x 2 (t) SYSTEM y 2 (t) output signals x n (t) y n (t) p - program Fig..2 Block diagram of system functioning. We distinguish miscellaneous systems such as: social, political, nervous, numerical, metric, solar, radio navigation, computer, and much more. In cybernetics and exploratory systems, it is assumed that the environment influences the system through input signals, which may be targeted at interactions (control, decisions) or

3 Introduction 3 disturbances interferencing with the objective of the system. An important feature of real systems are their dynamical properties. The properties are the cause of the presence of the system in an equilibrium rest, in the steady state or in a transient state which tends to an equilibrium or not. If dynamical properties are not essential, the system is treated as static [Zierep (978)]. Block diagram of a system built on the basis of that definition is shown in Fig..2. b b b S N 9.2 b b 2 4 a a 2 a P air a) b) S b c) b b 2 b 22 b 23 b 4 b 5 stop p 7 w a a 2 a 3 x Fig..3 A pneumohydraulic system of actuating control of a planer of corners of PCV windows: (a) pneumohydraulic scheme, (b) diagram of operation, (c) the controller [Lewandowski (25)]. The pneumohydraulic system depicted in Fig..3 is composed of the follow-

4 4 DYNAMICS OF MECHATRONIC SYSTEMS ing parts: strainer, 2 reducing valve, 3 manometer, 4 lubricator, 5-8 monostable divide valves 2/2, 9 bistable divide valve 5/2, pneumohydraulic actuator with mutual damping, position reed switches, 2 air lines, 3, 4 chock valves, 5 oil lines, 6 pneumohydraulic relay of pressure, 7 PLC controller, a i input signals, b ij output signals, x a signal starting the cycle, w power on or off, stop emergency turn off..3 Units of Measurement A physical quantity A is defined by a value {A} and a unit of measurement [A]: A = {A}[A], e.g. v = 3 [m s ], ρ =.29 [kg m 3 ]. (.) The unit of measurement is a specific measure of the physical quantity which serves as a template for the quantitative determination of other measures by comparison of these measures by numbers. By convention, the numerical value of the reference measurement is equal to, thus: [A] = A 45[m], e.g. [A] = = [m]. (.2) {A} 45 In the metric system of measurement (SI), there are 7 well-defined basic units and 2 supplementary units. Basic units include: ) meter [m] length, 2) ampere [A] electric current, 3) kilogram [kg] mass, 4) mole [mol] amount of a substance, 5) second [s] time, 6) candela [cd] luminous intensity, 7) kelvin [K] thermodynamic temperature. Supplementary units include: 8) radian [rad] plane angle, 9) steradian [sr] solid angle. β = [sr] β = [sr] φ = [rad] r r A = r 2 r Fig..4 Graphical representation of radian φ and steradian β. The currently used international system of units SI was adopted in 96 at the Ninth General Conference of Weights and Measures in Geneva. In mechanics, we use 3 basic units forming the MKS system, which are: meter [m], kilogram [kg], second

5 Introduction 5 [s]. The MKS measurement system is referred to as an absolute practical system of units. The abovementioned set of units is also a LMT system whose name comes from the first letters of the words: length, mass, time. The earlier absolute unit CGS system (a part of the LMT system) used in physics consists of centimeter [cm], gram [g] and second [s] (see in Table 3.). In the basic units one finds systems of various configurations. For example, 4-component LMTI or 6-component LMTIΘJ which distinguishes length, mass, time, electric current, thermodynamic temperature and brightness [Lerner and Trigg (25)]. Table. Abbreviations of secondary units. Name Abbr. Multiplicity Name Abbr. Multiplicity peta P 5 deci d tera T 2 centi c 2 giga G 9 milli m 3 mega M 6 micro µ 6 kilo k 3 nano n 9 hecto h 2 pico p 2 deka da femto f 5 Apart from the basic units, their derivatives are also used, which are associated with basic units by some respective dependencies. Derived units, for instance: [N] = [kg m s 2 ], [J] = [kg m 2 s 2 ], [Pa] = [kg m s 2 ], [W] = [kg m 2 s 3 ], and others. The basic units as well as their derivatives can act as main or secondary units. Main unit in its value is equal to, and its denotation does not have any prefix, e.g. [N], [kg], [J], [s], [Pa], [m], [W]. Secondary unit is greater or less than the main unit and is distinguished by a prefix specifying an increased or decreased multiple. For example, [kw] = [ 3 W], [cm] = [ 2 m], [ms] = [ 3 s], [µm] = [ 6 m], [MPa] = [ 6 Pa]. Non-SI unit is derived from the tradition of its application in a specific area. In automotive engineering, the unit of power often is horsepower [hp] = [.736 kw], in thermal engineering we speak about calorie [cal] = [4.9 J], in meteorology about tor, which is equal to the pressure exerted.