Transcript Automated Systems

Automated Systems
Chapter 10
What is an automated system?
An automated system is a way of
doing things automatically
INPUT
PROCESS
OUTPUT
Examples of Automated
Systems
Washing Machine
CD Player
Automatic Camera
Toaster
Vending Machine
Automated Systems in
Industry
Assembly lines
Car manufacture
Bread making
Microprocessor manufacture
Car wash
Why Use Automated Systems?
•Speed
•Accuracy
•Repetitive Tasks
•Efficiency
•Safety
Sensors
A sensor is a device which detects a
physical quantity:
Pressure
Heat
Light
Magnetic
Sound
Feedback
Uses sensors to detect what is going on
Can react to problems
Information from sensors is called
FEEDBACK
INPUT
PROCESS
OUTPUT
Traffic Lights with Feedback
Feedback from
Sensor
sensor
Traffic
Lights
Control
Computer
Control Information
Types of Robot
Stationery
The robot stays at
a fixed point all
the time – eg on an
assembly line
Mobile
The robot is
guided from one
location to
another
Robot Anatomy
Some robots have parts which look
human and are given human names
Each part of the arm is moved by a motor
Shoulder
Wrist
Tool
Elbow
Tools
You can get different types of tools
dependant on the job the robot has
to do
Gripper
Suction cup
Spray paint nozzle
Welding electrode
Programming Robots
Robots are controlled by a computer
program
Robots can be programmed by example –
this means a human will lead the robot arm
through the steps needed to perform the
task – this is also called LEAD THROUGH
PROGRAMMING
Once all the steps have been programmed
into the robot it can perform them over
and over again in exactly the same way
Control Languages
The program which controls the computer
is written in a programming language.
High level programming languages are
similar to English
Other programming languages are used
specifically for programming robots
Examples of programming languages are
BASIC, COMAL, FORTRAN and PASCAL
Social Implications
Automated systems have taken over
many manual jobs – computers are
quicker and cheaper than manual
labour
Workers may be retrained to operate
or maintain computer controlled
systems
But some may lose their jobs
Computers are reliable and last a long
time so little human contact is needed
Health and Safety
Negative Side
Long times operating a computer can
cause Repetitive Strain Injury or eye
strain.
Moving parts of automated systems
must be covered to prevent injury to
humans
People working with robots must be
very careful
Health & Safety – Positive Side
Because humans no longer
do hazardous jobs
industrial accidents should
be reduced
Robots can be used in
environments which are
hazardous or even deadly
for humans
Quality Control
Quality can be kept at a
consistent standard
The last item produced will
be of the same quality as
the first
Automated systems do not
become tired or bored
which can result in a
reduction in quality and
quantity of goods produced
Economic Implications
(costs)
Automated systems are
expensive to install
But, costs can be recovered by
increased productivity
Automated systems do not
demand pay rises
Automated Systems do not
demand good working conditions
Autonomous Guided Vehicles
(AGVs)
Magnetic Guidance – AGV follows wires laid
into the factory floor
Light Guidance – AGV follows lines painted on
the factory floor
Sensors – AGV detects objects or obstacles
in its way by using front and back sensors
Remote-controlled – Used when it would be
unsafe to send in humans – bomb disposal
Real-time Processing
A program that is constantly running
and ready to take action
If the sensors on an AGV detect an
object then the program must react
immediately to stop the vehicle
otherwise a person could be hit and
injured
Computer Aided Design
CAD is a way of using a computer to
design the structure or appearance of
an item on the screen
Uses of CAD:
Car Design
Kitchen Design
Road Design
Housing
Computer Aided Manufacture
CAM is using a computer to control
the production process
Advantages:
Faster and more accurate
Waste is minimised
Simple to operate and requires less
skilled operators
Simulation
A way of using computers to model
something that happens in real life
An engineer would know the effect of
various loading conditions on a bridge
without actually having to build it
An aircraft designer would know what
effect changing the shape of the wings
would have on the aircraft without having
to build the plane
Virtual Reality
A method of reproducing the outside
world digitally within a computer system
The world is then displayed to the user
through a headset
The user can interact with the virtual
environment using a data glove
Interface
Robots are connected to the
computer by an interface. The
interface sends the signals to the
robot telling it what processes to
perform
These signals are usually Analogue
Digital Devices
and Signals
A digital device has 2 states, either
on or off, e.g. a light switch is either
on or off
A digital signal is an electrical signal;
a high voltage = on = 1;
and a low voltage = off = 0,
and can be represented as a series of
1’s and 0’s i.e. ons and offs.
Analogue Devices
and Signals
An analogue device has a range of
values, e.g. a speedometer measuring
a range of speeds; or a light sensor;
or a pressure sensor.
An analogue signal varies in voltage
and if the voltage reaches a certain
value then the sensor can be
triggered to be “on”.
Analogue & Digital Signals
Computer only understands binary or
machine code. Most devices are
analogue measuring a range of values.
So, an Analogue to Digital (A to D)
converter is required.
But, when a computer sends signals
to control an analogue device then a
Digital to Analogue (D to A)
converter is required.
Analogue to Digital
Sensor
Feedback
Analogue
signal must be
converted to
digital
Traffic
Control
Computer
Interface
Lights
Digital signal
Control Information
Introducing Automated
Systems
A Systems Analyst looks at
how a job is done manually
Decides if the job could be
done better by an automated
system
Designs an automated system
to do the job
System is installed, evaluated
and monitored.
ROM Software
Stationery robots store their
programming on disk or tape
Robot can learn
Mobile robots store their
programming in ROM chips
Instructions are not lost when turned
off
Loads very quickly
Embedded Systems
An embedded system is a tiny
computer stored inside a larger piece
of equipment
Washing Machine
Car
Mobile Phone
They process data in real time
Control Languages
A language specially designed for
robot control
GRASP
MOVE
WAIT
TURN
Intelligent Robots
Expert System
+
Robot
=
Intelligent Robot
Bomb Disposal
Bomb disposal
robots make a
dangerous job a
little less hazardous.
They're designed to
search for, locate
and neutralize
explosive devices.
Nuclear Environments
American scientists
developed Pioneer
because of the
disaster at the
Chernobyl Nuclear
Power Station. The
robot was designed
to withstand large
doses of radiation
and was used for
clearing debris.
Factory of the Future?
24 hour a day production
No heat/light
Noisy
Dark
Cold
Technicians contained within a
control room
Task
Write a short essay on Automated
Systems:
Introduction
Advantages
Disadvantages
Conclusion
You may add illustrations
Expert Systems and Robots
We already know about Expert Systems
from our study of databases
An expert system can apply hundreds of
rules (learnt from a human expert) to a
particular field of knowledge
Expert systems combined with robots
could be used for such things as satellite
repair in space.