Automated Systems

What is an Automated System Typically automated systems have an Input Process Output

What is an Automated System The input may be manual or automatic The process will be carried out by the machine Finally the output is produced

Examples of Automated Systems In the home Toasters DVD players Washing machines Central heating controls

Examples of Automated Systems Out and about Traffic lights Automatic doors Drinks vending machine Parking ticket dispensers

Examples of Automated Systems In the work place CNC lathes Robot arms Mobile robots watch a clip of an automated system

Why use automated systems S A F F E R Safety Accuracy Faster Flexibility Efficiency Repetition

Safety Dangerous or unhealthy tasks are carried out by machines Spray painting cars Working with toxic chemicals Operating in dangerous environments

Accuracy Automated systems are more accurate than human beings They do not get tired They do not get bored They do not lose their concentration

Faster Automated systems can work faster than human beings

Flexibility Automated systems can be very flexible in what they can do Robots are reprogrammable Robots can have their end effectors changed to do new tasks

Efficiency Automated systems are more efficient than human beings because: They work 24 hrs a day without breaks 365 days a year without holidays Are never sick, do not strike and never ask for a pay rise once they are purchased

Repetition Lots of tasks carried out in factories are very repetitive These are best carried out by programmable machines that will continually repeat actions over and over again without deviation

Why use automated systems S A F F E R Safety Accuracy Faster Flexibility Efficiency Repetition

Types of control Open loop control system gives out control information Output Control computer Instructions

Types of control This does not involve feedback Open Loop Diagram Control computer Instructions Output

Types of control Closed loop control system uses feedback from a sensor Output Control computer Instructions Sensor provides feedback Traffic sensor

Closed Loop Diagram Control Computer control information output sensor feedback Watch a video clip

Types of control The sensor provides information to the control computer. This is called feedback. The control computer can (not will) alter the instructions to the output device. Closed Loop Diagram decision control information output feedback sensor

Types of control The difference between open and closed loop control An open loop system carries on regardless no matter what the circumstances A closed loop system uses feedback to alter the control information Watch a video clip

Robotics Two types of robots Stationary (Robot arms) Mobile watch a video clip

The anatomy of stationary robots This could be drawn like this Wrist Elbow Shoulder Waist End Effector waist shoulder elbow end effector wrist watch a video clip

Robots

Stationary Robots End Effectors can be of various types: Gripper Suction cup Paint spray Welding electrode Watch a video clip

Mobile Robots Autonomous guided vehicles Remote controlled vehicles

Autonomous guided vehicles AGV keep the production line in parts by fetching and carrying them from the warehouse to the assembly line

Autonomous guided vehicles AGV travel using: a magnetic guidance system a light guidance system

Autonomous guided vehicles All AGV will be fitted with sensors to detect unexpected objects in their path AGV will stop immediately if something is detected Communication with the control computer will be in real time

Remote controlled vehicles RCV are used in places where it is not safe for humans to go and are used in: Bomb disposal Nuclear power stations Toxic areas Deep sea exploration

Remote controlled vehicles RCV will be fitted with a variety of sensors and may include robot arms RCV are usually guided by a human using an optical sensor (camera)

Robots Each movable part of a robot is powered by an actuator which can be: Electrical Hydraulic (liquid pressure) Pneumatic (air pressure)

Robot arm movement One of the most important specifications of a robot arm is the number of degrees of freedom it has The number of ways the arm can move its movable joints

Robot arm movement The human arm The wrist can move up and down and left to right - two degrees of freedom The elbow moves in one plane only but the forearm can cross over- two degrees of freedom The shoulder can move in three planes and up and down – four degrees of freedom

Robot arm movement The robot arm has also got a waist which allows left to right movement – one degree of freedom waist

Degrees of freedom This is a measure of the number of movements which the joints can move. This example has 6 degrees of freedom Rotates base of arm Pivots base of arm Bends elbow Moves wrist up and down Moves wrist left and right Rotates wrist

Robot arm movement The terms roll, pitch and yaw are used to describe different types of movement Yaw is movement from side to side Pitch is up and down motion Roll is rotation

Robots Robots are connected to a computer by a device known as an interface An interface allows analogue and digital devices to communicate with each other

Interface- Analogue to Digital Analogue signal Digital signal Sensors provide analogue data Interface Computers use only digital data

Interfaces Analogue and digital conversion Movement and sensor readings are analogue - a variable signal Computers are digital 0’s and 1’s Conversion must take place

Interfaces A to D converters change the continuously varying analogue signal to digital D to A converters allow the computer to send instructions to analogue devices

Transducers + Digitisers A transducer is a device which changes external physical input into an analogue signal e.g. temperature sensors A digitiser converts a visual image from a video or television camera into a digital form

Programming robots Can be reprogrammed to do different tasks there are two ways to instruct a robot: Using a high level language – a control language (this is done remotely) Lead through method watch a video clip

Mobile robots Mobile robots may not be in contact with a control computer They will have control programs which are stored on ROM chips (Read Only Memory)

Simulators Simulators a developed to realistically recreate a real life situation These can be a model of a real life situation, testing a car or walking through a new building Or used for training – flying a plane or driving a car video

Simulators

Virtual Reality Virtual Reality is a method of producing the outside world digitally VR may require the user to wear a headset, which will have earphones and goggles and data gloves to input Users respond to computer generated graphics called Avatars Video

Virtual Reality

Implications of Automated Systems Social implications Job losses- less workers needed Job security New jobs- maintenance of A.S. New skills- programming

A systems analyst will also detail the design and layout of the factory System Analysis A systems analyst will determine what processes can be automated What machines will be best suited What computer systems and software are needed

Implications of Automated Systems Maintenance, testing and reprogramming of robot arm can be carried out on site

Implications of Automated Systems Technical implications – Safety People and machines kept apart as much a possible Special design or layout of factory Safety barriers and robot only paths

Implications of Automated Systems A typical automated car factory. Notice that there are no people about.

Implications of Automated Systems Technical implications – Safety Moving parts of machines covered Mobile robots move slowly and are fitted with sensors to detect obstacles Robots only carry out tasks when component is in position e.g. painting when car is in position

Implications of Automated Systems A factory layout for an automated system

Implications of Automated Systems Quality control Using automated systems the quality of the product can be kept consistent Manager monitor the system making changes if necessary

Implications of Automated Systems Economic Expensive to install Complete new factories may have to be built Long term “cheaper” than humans Productivity is increased

The Future “Intelligent robots” ? Expert systems will combine with robots allowing “thinking” machines which will apply rules more consistently than humans, explain their decisions and learn from their mistakes watch a video clip 1 watch a video clip 2 watch a video clip 3