Unit 1
Unit 1
Unit 1
LESSONS COVERED
DURATION: 6 Hours
INTRODUCTION
In recent times, the control system has played an essential part in the
field of engineering. Every aspect of our daily routine activities is affected by
the control system. This module will discuss what a control system is, why we
need to use it, what are the examples of control systems from simple to more
advanced ones. We will also use everyday examples to understand what
open loops and closed loops systems are and how they work.
OBJECTIVES
PRE-TEST
For us to understand what a control system is, let us first define two
terms: control and system. According to Merriam-Webster, a system is a
group of devices or objects forming a network that serves a common purpose.
While control is to regulate, manage, direct, or conduct. Therefore, a control
system can be defined as an order of devices or objects that are properly
connected in such a way to conduct a desired output.
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DEVICES FUNCTION
1. Cellphone A mobile electronic gadget that can
make phone calls, text messages, video
calls, and connect to the internet.
2.Microwave A device for swiftly heating and cooking
food using electromagnetic radiation.
3.Electric fan An apparatus used to move air around a
room or other enclosed place.
4. Speaker A device that transforms electrical
impulses into sound waves.
5.Flat iron A device used to straighten and style
hair.
The history of feedback and control systems can be traced back to ancient
times when humans first began to develop tools and technologies that allowed
them to control and manipulate their environment. For example, early
irrigation systems used feedback control to regulate water flow and ensure
crops received the right amount of moisture.
In the 18th and 19th centuries, engineers and scientists began to develop
mathematical models of physical systems and use them to design control
systems for machines and processes. The development of the steam engine
and other industrial technologies spurred the growth of feedback and control
theory, as engineers sought ways to improve the efficiency and reliability of
these machines.
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In the early 20th century, engineers such as Frederick Winslow Taylor and
Frank Gilbreth applied feedback and control principles to the field of
management, developing techniques for optimizing productivity and efficiency
in factories and other organizations.
During World War II, feedback and control systems played a crucial role in the
development of weapons systems and other military technologies. After the
war, these technologies were adapted for civilian use, leading to the
development of modern control theory and the widespread adoption of
feedback control systems in a variety of industries, including aerospace,
automotive, and process control.
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Feedback and Control System
There are two main types of control systems: open-loop and closed-loop.
Open-loop systems operate without feedback, meaning that the control
algorithm is not adjusted based on the system's output. Closed-loop systems,
on the other hand, use feedback to adjust the control algorithm based on the
system's output.
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applies the difference as a control signal to bring the process variable output
of the plant to the same value as the setpoint.
Let’s begin the lesson by performing the activity below for you to fully
understand the lesson. This section will introduce you to the lesson properly.
Complete the table by identifying and listing down the corresponding input
and output of the following control system. The first item is done for you.
Analysis
Congratulations on performing the first task. For you to move forward
you must understand and reflect first on your previous activity. Complete each
statement based on your experience.
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It made me aware of
The control system is a huge benefit to us, especially in our daily lives.
Abstraction
Now that you have understood the basic components of the control
system, we can now move forward to the classification or types of control
systems. There are two types of control systems: the open-loop system and
the closed-loop system, which both can be represented by a block diagram.
When we say block diagram, it uses blocks to show processes, and arrows to
connect input, processes, and output parts. We need also to define first a
control action. Control action is the quantity responsible for activating the
system to produce an output.
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Washing Machine
Bread Toaster
This machine operates as per adjusted time
regardless of toasting is completed or not.
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Feedback and Control System
Light Switch
Lamps glow whenever the switch is on, no matter
what the light is required or not.
Thermostat Heater
This machine senses the temperature of the system
and it maintains the temperature.
Missile Launcher
This device detects the position of the plane
using a radar tracking unit. The input is the
position of the plane, the plant is the launcher,
the controller is the computer system and the
output is the target.
Inverter AC
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Feedback and Control System
Feedback Systems are systems that decide the change of the input to
get the desired output. The processing part of a feedback system may be
electrical, electronic, or mechanical, ranging from a very simple to highly
complex circuits.
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produce a response that can differ substantially from the response produced
in the absence of such feedback.
This basic feedback loop of sensing, controlling, and actuation is the main
concept behind a feedback control system and there are several good
reasons why feedback is applied and used in electronic circuits:
Circuit characteristics such as the gain and response of the system can
be precisely controlled.
Circuit characteristics can be made independent of operating
conditions such as supply voltages or temperature variations.
Signal distortion due to the non-linear nature of the components used
can be greatly reduced.
The Frequency Response, Gain, and Bandwidth of a circuit or system
can be easily controlled within tight limits.
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Whilst there are many different types of control systems, there are just two
main types of feedback control namely: Negative Feedback and Positive
Feedback.
Application
This section will practice your understanding of the lesson.
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Predictability Stability
Accuracy
Complexity
REFLECTION/LEARNING INSIGHTS
1. After learning what a control system is, what do you think are the
advantages and disadvantages of the control system?
4. With additional learnings you have acquired, can you give more
control system example that you can find within your community.
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POST-TEST
Go back to our pre-test. List down all your answers on our first activity, identify
and classify them as open-loop systems, or closed-loop systems.
enclosed place.
using electromagnetic
radiation
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sound waves.
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