Control engineering

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Control systems play a critical role in space flight
Control systems play a critical role in space flight

Control engineering is the engineering discipline that focuses on mathematical modelling of systems of a diverse nature, analyzing their dynamic behavior, and using control theory to create a controller that will cause the systems to behave in a desired manner.

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[edit] Background

Modern control engineering is closely related to electrical and computer engineering, as electronic circuits can often be easily described using control theory techniques. At many universities, control engineering courses are primarily taught by electrical and computer engineering faculty members. Previous to modern electronics, process control devices were devised by mechanical engineers using mechanical feedback along with pneumatic and hydraulic control devices, some of which are still in use today.

The field of control within chemical engineering is often known as process control. It deals primarily with the control of variables in a chemical process in a plant. It is taught as part of the undergraduate curriculum of any chemical engineering program, and employs many of the same principles in control engineering.

Other engineering disciplines also overlap with control engineering, as it can be applied to any system for which a suitable model can be derived.

Control engineering has diversified applications that include science, finance management, and even human behaviour. Students of control engineering may start with a linear control system course which requires elementary mathematics and Laplace transforms (called classical control theory). In linear control, the student does frequency and time domain analysis. Digital control and nonlinear control courses require Z Transformations and algebra respectively, and could be said to complete a basic control education. From here onwards there are several sub branches.

[edit] Control systems

Control engineering is the engineering discipline that focuses on the modelling of a diverse range of dynamic systems (e.g. mechanical systems) and the design of controllers that will cause these systems to behave in the desired manner. Although such controllers need not be electrical many are and hence control engineering is often viewed as a subfield of electrical engineering. However, the falling price of microprocessors is making the actual implementation of a control system essentially trivial[citation needed]. As a result, focus is shifting back to the mechanical engineering discipline, as intimate knowledge of the physical system being controlled is often desired.

Electrical circuits, digital signal processors and microcontrollers can all be used to implement Control systems. Control engineering has a wide range of applications from the flight and propulsion systems of commercial airliners to the cruise control present in many modern automobiles.

Control engineers often utilize feedback when designing control systems. For example, in an automobile with cruise control the vehicle's speed is continuously monitored and fed back to the system which adjusts the motor's torque accordingly. Where there is regular feedback, control theory can be used to determine how the system responds to such feedback. In practically all such systems stability is important and control theory can help ensure stability is achieved.

Although feedback is an important aspect of control engineering, control engineers may also work on the control of systems without feedback. This is known as open loop control. A classic example of open loop control is a washing machine that runs through a pre-determined cycle without the use of sensors.

[edit] See also

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[edit] Literature

  • Christopher Kilian (2005). Modern Control Technology. Thompson Delmar Learning. ISBN 1-4018-5806-6. 

[edit] External links


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