Automation Systems Lecture 1 - Basic concepts / Control system design Jakub Możaryn

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Automation Systems

Lecture 1 - Basic concepts / Control system design

Jakub Możaryn

Institute of Automatic Control and Robotics, Department of Mechatronics, WUT

Warszawa, 2017

Jakub Możaryn Automation Systems

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Programme

Information about lectures and laboratories Automation Systems, lecture - Jakub Możaryn, PhD, Eng., semester IV - lecture (20 hours), Faculty of Mechatronics, room.

346, e-mail: jmozaryn@gmail.com, webpage:

http://jakubmozaryn.esy.es

Automation Systems, laboratory - Jakub Możaryn, PhD, Eng., Jędrzej Mączak, Przemysław Szulim - (10 hours)

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Programe

Lecture information Lecture - 20 hours

Laboratory - 10 hours Work at home - 20 hours Exam preparation- 10 hours

Conditons: pass the writing exam and attend all laboratories ECTS points - 3

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Literature

R.C. Dorf, R.H.Bishop, Modern Control Systems, Prentice Hall, 2008

G.F. Franklin, J.D. Powell, A. Emami-Naeini, Feedback Control of Dynamic Systems, Addison-Wesley, 1994

N.S. Nise, Control Systems Engineering, Wiley, 2015 on-line MOOC courses: Coursera, EdX, Iversity

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Introduction

Today, many devices are equipped with what is generally called

automation. Ranging from household appliances like iron (temperature controller), washing-machine (programmer) to devices with the most advanced technology as the aircraft (autopilot).

One of the first controllers, which has been applied in practice was Watt’s regulator to stabilize the rotation of the steam engine (1784).

Since then, automation has become a type of science, and the number of its practical application is constantly growing. The theory of automatic control, now includes

theory of linear systems, theory of nonlinear systems, optimal control,

theory of discrete systems (logical automation systems), robotics.

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Programme

Lectures aims

Acquiring the ability to recognize and assess the problems of automation and control.

Assimilate the basic concepts of automation of different processes, methods to determine the nature and elements of automation of continuous and discrete action.

Understanding the basic principles of operation of control systems and functions of the elements making up these systems.

Understanding the requirements for systems of regulation and methods of ensuring the fulfillment of these requirements.

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Programme

Introduction: basic concepts, classification of control systems of continuous processes, examples.

Methods for description of dynamical systems: differential equations, transmittances, time and frequency characteristics.

Features static and dynamic basic blocks.

Seting and reducing block schemes of systems.

Objects of control and identification of objects.

PID controllers.

Stability of control systems, stability criteria.

Static and dynamic indicies of control quality, selection of parametrs of controlers.

Designing a control systems.

Complex control systems: cascade control, correction dynamic adjustment of ratio: single loop and cascade,

Disturbance compensation systems, closed-open systems.

Nonlinear control systems: two- and three-state controllers.

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Basic concepts

Control System

Control System is an interconnection of components forming a system configuration that shall provide a desired system response (behaviour).

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Basic concepts

Open-loop control system

Examples:

Toaster

Cofee vending machine

Signals y_r(t) - desired output response

u(t) - control signal x (t) - input signal y (t) - output signal

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Basic concepts

Closed-loop control system

Examples:

A temperature control in a greenhouse

A water level control in a tank

An automatic pilot

Signals u(t) - control signal x (t) - input signal y (t) - output signal yr(t) - desired output response

ym(t) - measured output e(t) = yr(t) − ym(t) - error signal

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Basic concepts

Closed-loop feedback control system

Control system that tends to maintain a prescribed relationship of one system variable to another by comparing functions of these variables and using the difference as a means of control

error signal e(t) is amplified

controller causes the actuator to modulate the process in order to reduce the error e(t)

Feedback concept

A closed-loop control system uses a measurement of the output and feedback of this signal to compare it with the desired output (reference or command).

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Basic concepts

Closed-loop control system

Elements

C - controller, A - actuator, O - process/object, S - sensor Main Path indicates always an essential input value of the system and output value. This path typically illustrates the main flow of material or energy in the system.

Feedback Path is used to transmit information. Energy requirements of this path is usually small, and can be ommited.

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Basic concepts

Closed-loop control system - disturbances and noise

Advantages of the closed-loop control system over open-loop control system

rejects external disturbances d (t),

improves measurement noise n(t) attenuation.

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Basic concepts

Closed-loop control system - simplified scheme

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Basic concepts

Multi-loop Feedback Control System

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Basic concepts

Single Input Single Output - SISO system

Multiple Input Multiple Output - MIMO system

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Example - autopilot in cars

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Example - autopilot in cars

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Example - autopilot in cars

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Example - autopilot in cars

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Example - autopilot in cars

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Example - DARPA Challenge, USA

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Control System Design

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