Standard Grade Computing Studies
Automated Systems
Fra nk Fr a m e
Computing Studies
Standard Grade
Automated Systems
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Acknowledgement
Thanks to Dorothy Tedman for her contribution to the review of the content.
First published 2004
This publication may be reproduced in whole or in part for educational purposes by
schools and colleges in Scotland provided that no profit accrues at any stage.
ISBN 1 84399 039 3
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Contents
Introduction
4
The Reasons for Using Automated Systems
6
Computer-Aided Design (CAD)
9
Computer-Aided Manufacture (CAM)
10
Virtual Reality
11
Using Software
11
Analogue to Digital
13
Using ROM Chips
15
Using Real-time Processing
15
The Glasgow Science Centre Tower
15
The Costs of Automated Systems
16
Retraining
17
Designing a Modern Workplace
17
Safety Systems
18
Automated Systems Questions
19
Automated Systems Answers
21
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Introduction
This publication is part of a series of publications to support Standard Grade
Arrangements in Computing Studies (March 2004). The titles in the series are:
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General Purpose Packages
Communications and Networks
Computer Systems
Automated Systems
Commercial Data Processing.
The first two packs, General Purpose Packages and Communications and
Networks, provide complete coverage of the content as specified in the updated
arrangements for Standard Grade Computing Studies.
The other three packs, Computer Systems, Automated Systems, and Commercial
Data Processing have been produced to support the three programmes featured
on the DVD. The content of these materials has been written to relate directly to
the programmes on the DVD and may not cover all the content as specified in the
course arrangements.
Automated Systems
The materials contained in this pack support the programme on the DVD entitled
Dreaming in Digital. The materials cover automated systems at a variety of
different companies and organisations such as Aberdeen Traffic Control Systems,
Department of Informatics at Edinburgh University, Glasgow Science Centre, Linn
Systems and Torness Nuclear Power Station. The materials cover the following
content as specified in the course arrangements.
Note: Credit level is marked in this document with shading.
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Automated Systems –
Content covered in support materials
Main
Aspect
F/G/C
G/C
Need
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efficiency
accuracy
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adaptability
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analogue I/O
interface guides
- magnetic and light
simulation
virtual reality
real-time processing
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speed
hazardous environment
repetitive tasks
sensors
feedback
robots
anatomy
motor
programmable
stationary/mobile
tools
CAD/CAM
A to D and D
to A converters
control
language
ROM software
embedded
systems
intelligent
robots

retraining

Hardware and
Software
Implications
- Social
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- Technical
- Economic
C
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employment
- changes in nature
of job
industrial automation
safety precautions
high initial cost
long term savings
replacements costs
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design of
workplace
modern factory
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The Reasons for
Using Automated Systems
As this table shows, the programme makes clear the reasons why automated
systems are needed.
Reasons for using automated systems
Example from the programme
They operate at high speed.
Linn Systems uses automated
systems to produce circuit boards at
very high speeds.
They can handle repetitive tasks without making
mistakes.
Aberdeen Traffic Control Centre uses
automated systems to monitor traffic
flow by repeatedly counting vehicles
as they pass through road junctions.
They are accurate.
The automated systems in Torness
power station use sensors accurately
to monitor and control the use of
nuclear energy to produce electricity.
They work in dangerous places where it is
unsafe for people to work.
Automated systems work in areas of
Torness nuclear power plant where it
would be very dangerous for people to
work, monitoring electrical voltages,
radiation levels and the acidity levels
in the water purification plant.
Adaptability
Automated systems are very adaptable because they can be re-programmed and, in
the case of robot arms, fitted with different tools to enable them to carry out different
tasks.
In the programme a good example of this is Linn Systems where the robot arms can
be quickly re-programmed to work on different types of circuit board.
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------------------------------------------------------------------------------------------------------Automated systems use sensors to gather data and feed it back to the processor. In
the programme you saw a wide range of sensors being used.
Sensor
Example from the programme
Pressure sensor
Front of the
mobile
robot
Infra-red sensor
Aberdeen Traffic
Control points at
traffic lights
Edinburgh
University robots
Magnetic sensor
Linn Systems Mobile robots
Induction loop: electromagnetic
sensor
Light sensor
Aberdeen Traffic Control points at
traffic lights
Edinburgh University robots
Radiation sensor
Torness Nuclear Power plant
Sensors detecting the levels of acidity
in a water purification plant
Torness Nuclear Power plant
There are two main types of robot you need to know about: stationary robots and
mobile robots. There are examples of both in the programme.
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Stationary Robots
These are robots that are fixed in
position. The diagram below shows
a large-scale stationary robot arm.
It has mobile joints called ‘the wrist’,
‘the elbow’, ‘the waist’ and ‘the
shoulder’.
Changing the tools on
a Robot arm
A whole range of tools can be fitted to the end of a robot arm, for example a spray gun, a welding
gun, a gripper, etc.
In the Linn Systems factory the robot arms were relatively small, were fitted to the production line and
had a tool fitted to enable them to place parts on the circuit boards. This tool could be changed to
enable the arm to place a range of different electronic parts on the circuit board.
Mobile robots
Mobile robots move around using wheels or tracks and are usually powered by electric motors.
Guiding mobile robots
Two ways of guiding a mobile robot are magnetic guides and light guides.
Magnetic guides
Magnetic guides work as follows.
1.
2.
3.
A cable buried in the floor
gives off a magnetic field.
Sensors suspended
underneath the robot detect
the magnetic field and feed
the data back to the
processor controlling the
robot.
The processor then uses this information to send out signals to control the direction of the
robot’s wheels.
In the Linn Systems factory the mobile robots, which are used to carry materials around the factory
floor, used magnetic guides to follow the cables buried in the factory floor.
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Light guides
Using this method the robot follows a path marked out by a white line painted on the floor as follows.
1.
2.
3.
The robot shines a light on to the floor.
This light is reflected back off the white line and is picked up by light
sensors that are positioned underneath the robot.
The information about reflected light is fed from the sensors back to
the processor. Then, just as with magnetic guides, the processor
uses this information to send out signals to control the movement of the robot.
Computer-Aided Design (CAD)
CAD systems are used to produce designs and plans of everything from buildings to
aeroplanes, from conservatories to mobile phones.
Why use CAD systems?
Reasons
Example from the programme
It is much easier to produce complex
drawings using a CAD system than it is
to do it by hand.
Linn Systems used CAD to design their
circuit boards.
Altering a drawing is a simple process of
making the change and saving the new
version to disk. By hand the whole
drawing would have to be done again.
Producing multiple copies of a design is
straightforward: it is simply a matter of
printing out as many copies as are
needed by sending them to the printer.
What kind of hardware do CAD systems need?
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High resolution monitors
Powerful processors
High-capacity backing storage
Graphics tablet
Plotter
You can find out more about hardware in the Computer Systems programme and support notes.
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Computer-Aided Manufacture (CAM)
In industry many factories use computers to control machinery during manufacture.
Some industries have an
integrated CAD/CAM system where
objects are designed using a CAD
system. This design is then fed directly
to the computer that controls the
machinery and robots are used to cut
out the parts or assemble the finished
product. Linn Systems uses a
CAD/CAM system to produce its circuit
boards. Once the designs for the circuit
boards are completed using the CAD
system, they are transferred directly to
the computer systems that control the
robot arms. The robot arms then
assemble the circuit boards.
Simulation
A computer simulation is the use of the computer system to mimic a complicated activity in the real
world such as driving a train or flying a plane.
A simulation will allow the user to input control signals,
for example using a joystick to control a simulation of a
plane flight. The signals are then processed by the
system, which reacts to the signals by changing the
display on the screen, for example, the plane starts to
dive to the ground.
Computer simulations are used:

to teach people skills in a safe environment. You
can learn to drive a train or fly a plane on a
simulator without any danger to yourself, or
anyone else. In the programme you can see how
Torness nuclear power plant uses a simulated
control room, which is identical to the real control
room, to train its operators

for games.
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Virtual Reality
Virtual reality systems use stereo vision screens and surround sound to make the user feel as if they
are actually inside the computer’s world.
Virtual reality systems even let the user move
around the virtual world and manipulate it by
touching and moving objects. This is done by
building sensors into the gloves, helmet and even
suits, that the user wears while in the virtual world.
Glasgow Science Centre has a virtual reality theatre
that can be used by designers to inspect their virtual
CAD models.
Using Software
Automated systems are controlled using software.
This controlling software contains instructions about what an automated system has to do. Take the
example of the robots being developed at Edinburgh University: the actions of the robots and the way
they react to the data being fed to them by their sensors are controlled by the instructions in the
controlling software.
These instructions are written using a control language that has features such as special
commands for controlling robot movements, for specifying the degrees of rotation of robots arms,
and special input/output facilities.
Control language has instructions that the programmer can use to tell a robot which way to turn,
how high to lift up the gripper, how far to travel or even to control the speed of the motor.
Using embedded systems
Embedded systems are found in machines. An embedded system is a single processor that has
a few simple functions to carry out. Modern car engines have embedded systems, as have
mobile phones and other electronic equipment such as digital cameras and games consoles.
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An embedded system gives the user a simple control interface such as a touch screen with a
simple menu and/or a couple of control buttons. Embedded systems are based on the use of
microprocessors such as the Intel Pentium’s ‘M’ processor, which is specially designed for lowpower embedded systems.
Intelligent robots
Intelligent robots have a range of sensors attached to them as well as their own powerful onboard
processors, and significant memory capacity. All of which enables them to mimic the capacities of
the human senses.
How can they mimic human senses?
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They can ‘hear’ commands using microphones and sound and/or voice recognition systems.
They can use sonar beams and sensors to detect objects.
They can see objects using optical sensors.
They can, using tactile sensors, tell the differences between various types of surface, for
example, tiled floors, soft carpet.
Some even move about using human-like legs.
These sensors, combined with powerful onboard processors and large memory capacity, mean
that robots of this type are very flexible and can react to the environment they are working in. This
in turn means that they can be used for a wide range of complex functions that require the robot to
gather, process and react to stimuli.
Where are they used?
In space exploration, in undersea work, for example, on undersea pipelines. They are commonly
used to clean out swimming pools.
In the programme we saw a range of experimental intelligent robots being developed at Edinburgh
University.
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Robot
The robot that
followed a person
around a room.
Illustrating
The ability to mimic the
human ability to ‘see’.
The robot that
moved towards a
sound.
The ability to mimic the
human ability to ‘hear’.
The robots that used
infra-red sensors to
avoid objects.
The ability to mimic the
human ability to ‘see’
and detect obstacles.
Analogue to Digital
To understand how sensors feed data back to a processor, let us look at the example of the
magnetic sensor attached to the mobile robots in Linn Systems.
As a robot moves along the factory floor, the sensor detects the magnetic field and, as levels rise and
fall, it sends an electrical current back to the processor. This current rises and falls along with the
strength of the magnetic field. Because it rises and falls continuously this signal is known as an
analogue signal.
If we were to draw an analogue signal it would look like a rising and falling wave.
An interface is used to change the analogue signal into digital form so that the processor can deal with
it.
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An A to D converter is an interface that changes analogue signals into digital
form. It does this by sampling the incoming analogue signal thousands of times
per second and changing the samples into digital numbers. A to D converters are
used to change the analogue signals coming from the magnetic sensors attached
to the mobile robots in the programme into the digital form that the controlling
processor can accept and understand.
A D to A converter is an interface that changes digital information to analogue
form, reversing the process of an A to D converter. The D to A converter is
used when the processor is sending signals out, for example, to control the
speed of a mobile robot or to change the direction of its wheels.
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Using ROM Chips
Automated systems often store the controlling software and the software that carries out the
A to D–D to A conversion on ROM chips. The advantage of this is that the instructions in the
software are immediately available to the processor without having to be loaded from
backing storage.
Using Real-time Processing
In real-time processing the system reacts instantly to data fed back to the processor from sensors.
Take the example of how the Aberdeen traffic control system operates.
1.
2.
The incoming analogue signals from the infra-red traffic sensors are converted into digital
form.
This digital data is then sent to the controlling computer system, which processes it and reacts
instantly to control the traffic lights and keep the traffic flowing.
Real-time processing enables the traffic control system to react instantly to control the lights and
regulate the flow of traffic.
The Glasgow Science Centre Tower
Glasgow Science Centre Tower is a spectacular example of an automated system. The giant tower
has a viewing platform that you can reach by a lift. From there you can see a panoramic view of the city
of Glasgow and the surrounding countryside.
The tower has two special features.
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It has a special streamlined shape so that it can face
directly into the prevailing wind.
It can be rotated to face into the wind.
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How is an automated system involved?
It rotates the tower according to the prevailing wind speed and direction.
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The tower sits on large rollers which are turned by powerful electric motors.
The motors are controlled by a computerised control unit.
Sensors on two weather stations, one at the top of the tower and one near the bottom, gather
information about wind speed and direction, temperature, humidity and rainfall. The data from
the wind speed and direction sensors is fed to the control unit at the base of the tower by
using radio modems.
The control unit then processes this data before sending control signals to the motors to adjust
the position of the tower.
The Costs of Automated Systems
Initial costs
It takes a lot of money to set up an automated system. The following list gives you an idea of some of
the things that might need to be paid for:
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Stationary robots
Mobile robots
Guidance systems for the mobile robots
Sensors, software
Computer systems
Installation of cables, etc.
Linn Systems, Aberdeen Traffic Control System and Torness Power station have all invested
millions of pounds in their automated systems.
Why do businesses and organisations invest so much on
automated systems?
One reason is because automated systems make businesses run efficiently and, in the long term,
save money.
Linn Systems depend on their automated
systems to maintain a high rate of
production and to produce electronic
goods of the highest quality. The
automated assembly line guarantees
precision and produces high-quality circuit
boards much faster than any manual
system could.
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Aberdeen traffic control system uses the automated system because it is the most efficient way
of controlling traffic flows around the city.
And, of course, using automated systems means a reduction in the number of people required to do
the work, cutting down on the wage bill.
Another reason is safety.
Automated systems can operate in environments that would be very dangerous to humans: Torness
power station relies on automated systems to ensure that power is produced efficiently and, above
all, safely.
Retraining
When automated systems are introduced into a workplace people need to be trained to work with the
new system. Staff members in Linn Systems have had to be trained to carry out a range of tasks
such as:

using the controlling software
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maintaining the robots and the robot arms
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supplying the robot arms with parts
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working safely alongside the mobile robots.
Designing a Modern Workplace
When a factory introduces an automated system the entire layout has to be
redesigned.
The entire layout of the Linn Systems factory has been designed specifically to
accommodate both the automated production lines with their stationary robot
arms and the mobile robots. The following are key features of the design of the
factory.
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The location of the stationary robots
The paths for the mobile robots
The installation of the cabling
Safety zones
The number, type and location of the computer systems
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Safety Systems
Safety is important, especially when robots are being used. They can be dangerous and precautions
have to be taken.
What safety measures can be taken?
Mark out the areas where automated systems are operating by:

painting hatched areas on the
floor in bright yellow

hanging up signs.
Mobile robots can be fitted with flashing
lights and sirens.
Sensors can be fitted to mobile robots to
detect when they come into contact with
objects. All of these safety precautions
are in place in the Linn Systems factory.
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Automated Systems Questions
1. Complete the following table using examples from the programme
Reason for using automated system
Example from the programme
They operate at high speed
Linn Systems use automated
systems to produce circuit boards
at very high speeds.
They can handle repetitive tasks without
making mistakes.
They are accurate.
They work in dangerous places where it is
unsafe for people to work.
2.
3.
4.
5.
6.
7.
What kind of tool was fitted to the robot arms making the circuit boards?
Describe the job being done by the mobile robots in the Linn Systems factory.
What kind of guidance system did the Linn robots have?
How did this type of guidance system operate?
List the sensors attached to the Linn Systems mobile robots.
List the sensors used by: (a) Aberdeen Traffic Control System (b) Torness Nuclear Power
Plant.
8. What was the job of the sensors in (a) Aberdeen Traffic Control System (b) Torness Nuclear
Power Plant?
9. What are the reasons for using CAD?
10. What did Linn Systems use CAD for?
11. Describe how CAD linked up with CAM in the Linn Systems factory.
12. What was the CAM system used for in the Linn Systems factory?
13. How do virtual reality systems make the user feel as if they are actually inside the computer’s
world?
14. Describe an example of a virtual reality system you saw in the programme.
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15. (a) What are embedded systems? (b) What are they used for?
16. What is an intelligent robot?
17. Why could the robots being developed at Edinburgh University be described
as intelligent?
18. Complete this table setting out the sensors that the Edinburgh University
intelligent robots used and the human senses they mimicked.
Sensor
Human senses
19. Why does the Aberdeen Traffic Control System need interfaces?
20. What is the job of a D to A converter on the automated system controlling the
robot arms in the Linn Systems factory?
21. What is the job of a D to A converter on the mobile robots?
22. The Linn Systems factory has been designed specifically for working with
automated systems. List the key features of the design of the factory.
23. Which sensors does the Glasgow Science Centre Tower use?
24. Why is an automated system used to control the position of the tower?
25. A salesman is trying to sell a mobile robot to a factory owner. The factory
owner hesitates because the robots are very expensive to buy. What could
the salesman say to convince him that the investment would be worthwhile?
26. What training would people require to work alongside the mobile robots and
robot arms in the Linn factory?
27. What safety measures would you put in place (a) around a stationary robot?
(b) on and around a mobile robot?
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Automated Systems Answers
1.
The table below shows examples for each reason for using automated systems. You might
want to use other examples from the programme.
Reason for using
automated system
They operate at high speed
They can handle repetitive
tasks without making
mistakes.
They are accurate.
They work in dangerous
places where it is unsafe for
people to work.
2.
3.
4.
5.
6.
7.
8.
Example from the programme
Linn Systems uses automated
systems to produce circuit boards at
very high speeds.
Aberdeen Traffic Control Centre uses
automated systems to monitor traffic
flow by repeatedly counting vehicles
as they pass through road junctions.
The automated systems in Torness
power station use sensors to
accurately monitor and control
radiation.
The automated systems work in areas
of Torness nuclear power plant where
it would be very dangerous for people.
It was a specialised tool for fitting the electronic parts on to the
circuit boards.
They were being used to carry materials around the factory floor.
Magnetic guidance.
Cables were buried in the floor to mark the robots’ path. The cables
produce a magnetic field that is detected by the sensors attached to
the robot. The sensors pass this data to the controlling processor that
uses it to control the direction in which the robot moves.
Magnetic sensor, infra-red sensor, pressure/bump sensor.
(a) infra-red sensors on the traffic lights, induction loop electro- magnetic sensors buried in
the roads (b) Sensors measuring temperatures, voltages, radiation and sensors
monitoring the other sensors.
(a) To gather information about the number and frequency of vehicles
on the roads and at junctions (b) To gather data about the processes involved in producing
power including: temperatures, voltages and radiation to enable the operators to control the
production process.
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9.
The reasons for using CAD are as follows.
It is much easier to produce complex drawings using a CAD system than it is to do it by hand.
Altering a drawing is a simple process of making the change and saving the new version to
disk. By hand the whole drawing would have to be done again.

Producing multiple copies of a design is straightforward: it is simply a matter of printing out as
many copies as are needed by sending them to the printer.
10. To design their circuit boards.
11. Once a design was completed it was sent, in digital form, through a network to the computer
systems that controlled the robot arms on the assembly line.
12. Controlling the robot arms that place the electronic parts on to the circuit boards.
13. Virtual reality systems use stereo vision screens and surround sound to make the users feel
as if they are actually inside the computer’s world.
14. The virtual reality theatre in the Glasgow Science Centre was used by
designers to test stress points in a new car, by scientists to analyse
molecular structures and by town planners to design a new town.
15. An embedded system is a single processor that has a few simple functions to carry out.
Modern car engines have embedded systems as have mobile phones and other
electronic equipment such as digital cameras and games consoles.
16. An intelligent robot is a robot that has a range of sensors attached to it as well as its own
powerful onboard processors, and significant memory capacity. These sensors enable it to
mimic the capabilities of human senses.
17. Because they had a range of sensors linked to processors that
enabled them to mimic human senses.
18. Complete this table setting out (a) the sensors that the Edinburgh
University intelligent robots used (b) the human senses they mimicked.
Sensor
Human Senses
Microphones
Hearing
Infra-red sensor
Seeing


19. To change the analogue signals that come from the sensors into the digital form that the
controlling processors can understand.
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20. It changes the digital instructions from the processor into analogue signals. These analogue
signals are used to control the electric motors that move the robot arms.
21. It changes the digital instructions from the processor into analogue signals that control the
electric motors that turn and move the wheels, and apply and release the brakes.
22. The key features of the design of the factory are:
 the location of the stationary robots
 the paths for the mobile robots paths
 the installation of the cabling
 safety zones
 the number, type and location of the computer systems.
23. It uses sensors to detect wind speed and direction.
24. Because it can react accurately and quickly to changes in wind direction and adjust the
position of the tower accordingly.
25. He could say that the investment would, in the long term, actually make the business money
because it would increase efficiency and reduce the wages bill.
26. People would have to be trained in:
 using the controlling software
 maintaining the mobile robots and robot arms
 supplying the robot arms with parts
 safety procedures.
27 (a) Brightly painted ‘robot only’ areas on the floor, warning signs hanging near the robots
(b) Flashing lights, sirens, collision sensors.
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