Курчаткина Г.П., Стручкова С.Б. Обучение чтению литературы на англ.языке по спец. САУ для студентов старших курсов (2014) (1257062), страница 6
Текст из файла (страница 6)
The principles to be discussed in this article can be applied equally well to bothpneumatic and electronic controllers.5. James Watt invented the flyball governor as a mechanism to control the speed ofa steam engine that did not require human intervention.6. Schmidt was the first to introduce the idea of evaluating partial derivatives at theestimated value of the state variables.7. Optimization can be regarded as a branch of mathematics whose goal is toimprove a variable in order to maximize a benefit (or minimize a cost).8.
Airy was the first to discuss the instability of closed-loop systems, and the firstto use differential equations in their analysis.9. Maxwell’s technique was to linearize the differential equations of motion to findthe characteristic of the system.10. Due to the increasing complexity of the systems to be controlled and theinterest in achieving optimum performance the importance of control systemengineering has grown immeasurably.Humans have always sought to increase the capability of their tools and theirextensions, i.
e., machines.34Exercise 4. Translate the sentences into Russian paying attention to InfinitiveConstructions.1. The feedback is said to be negative when the error signal is the differencebetween the desired value and the measured output value from the process.2. The potential future application of feedback control systems and models appearsto be unlimited.3.
The noisy measurements of the object's coordinates at ten different points on itsorbit are believed to be equally reliable.4. The mechanism has proven to be very effective in detecting faults in somediagnostic sources.5. This expertise requirement appears to be the main reason why predictive controlis not used as widely as it deserves to be.6. The theory and practice of modern control systems seems to have a bright andimportant future and is certain to justify the study of system modern automaticcontrol theory and application.7. The Kalman filter is also used for predicting the likely future courses of dynamicsystems that people are not likely to control, such as the flow of rivers duringflood, or the trajectories of celestial bodies.8.
One basic concept is that for the automatic feedback control to exist theautomatic control loop must be closed.9. Lack of good mathematical tools is a fundamental problem for fuzzy control toovercome.10. For satellites or space vehicles to accomplish their mission their orientation andposition in space often require extremely precise management performed byonboard control systems.11. The author believes his course to provide the students with a breadth of designexperiences, and also to make them think about the design of controllers as anongoing process for which the theory provides a set of analysis tools.3512. Experience shows robust controllers to have been designed with relatively littleeffort by following a few simple rules.Exercise 5.
Translate the sentences into Russian paying attention to different typesof clauses.1. If the transmitter does not send an accurate signal, or if there is a lag in themeasurement signal, the ability of the controller to manipulate the process will bedegraded.2.
The basic idea of a feedback control loop is most easily understood byimagining what an operator would have to do if automatic control did not exist.3. Once we have done this, we do need to check whether the aircraft meets all therequirements.4. To verify that a set is a subspace, all we need to check is that the subset is closedunder vector addition and under scalar multiplication.5. Although fuzzy control has great potential for solving complex controlproblems, its design procedure is complicated and requires a great deal ofspecialty.6. The process requirements are compared with the process response in thecontroller whose task is to generate actions that ultimately bring the process inline with the required state.7.
Digital control offers distinct advantages over analog control, which explains itspopularity.8. Based on a comparison of the signals, the automatic controller can tell whetherthe measurement signal is above or below the set point and move the valveaccordingly until the measurement (temperature) comes to its final value.9. The underlying idea that motivated this article is that Control Theory is certainto be, at present, one of the most interdisciplinary areas of research.10.
As the speed increases, the response shows a marked reduction in steady stateerror and a less damped transient response.3611. An important point to remember when using summing or comparison devicesis that the inputs and outputs to/from the device must all have the same units.12. This is the prototype of what is known as the Kalman filter.13. The subjects we address range from the basic concepts related to the dynamicalsystems approach to mathematical programming and calculus of variations.14. Whether these two phenomena are related has yet to be discovered.15.
The question was why learning control application has never been popular.16. That feedback may create instability is a well-known fact.17.Should any of the relevant plasma parameters go outside the allowed range, theenable signal would be removed and the systems turned off.18. What distinguishes an automatically controlled system is that it possessesworking components which maintain at least some of its typical processes despitesuch excessive variations.GlossaryThe following glossary provides definitions utilized to describe a generic controlsystem.
The words are not in an alphabetical order, rather, in a logical one.• To control means to maintain a particular operation, status or performance of aphysical process• Controlled plant or controlled process is the physical process, i.e. thecombination of physical transformations which must be maintained according to aprecisely defined operational regime.• Controlled variable represents quantitatively the actual operation, status orperformance of the controlled process.• Control system is a combination of components performing control functions. Acontrol system typically forms a closed-loop with the controlled process.• Actuation signal symbolizes the control efforts applied to the controlled plant inorder to provide the desired effects on its status or performance.37• Sensor is the primary measuring element that is affected by the controlled(measured) variable change, usually it might be a change in resistance orinductance or capacitance element or a small mechanical movement.• Transducer (transmitter) is a device that transforms a controlled variable into anelectrical signal thus providing the quantitative characterization of the actualoperation, status or performance of the controlled process.• Set point (reference) is the signal that represents the desired operation, status orperformance of a controlled process.
The controlled variables are represented byparticular low power electric signals following some scale. Thereference signals have the same order of magnitude and power as the signalsrepresenting controlled variables, but are defined by the human operators of theprocess.• Disturbance signals represent all external (and sometimes internal) factors thatresult in the undesirable deviations of controlled variables from their requiredvalues. (e.g. thermal process with opened door)• Noise signal is unwanted random signal in the measuring device or in theprocess.• Error detector is the element to generate the error signal.• Error signal is the difference between the actual and desired values of controlledvariable, or between the reference and transducer output signals.• Controller is an analog or digital device that defines the control effortstransforming the error signal into the control signal, in accordance with the controlstrategy.• Servomechanism is an electric, hydraulic or pneumatic device that performspoweramplification of the control signal, generating a control effort.• Actuator (final control element) is the device, driven by the servomechanism,which directly affects the controlled process by applying the actuation signal.• Stable control system is the system that maintains the controlled variable at its38desired value.Latin Words and Abbreviationsab ovo – c самого началаA.D.
(anno domini) – нашей эрыad hoc – специальныйa.m. (ante meridiem = before noon) – до полудняa posteriori – основанный на опыте; из опытаa priori – априорный; априори, независимо от опытаB.C. (before Christ) – до нашей эрыcf. (confer = compare) – сравниc.,ca (circa) – приблизительно, околоe.g. (exempli gratia = for example) – напримерet al. (et alii =and others) – и другиеetc.