CS02 : Data capture

In this section, we take a look at the different ways what data can be 'exchanged' between computer systems and the outside world.

We are learning ...
  • About data capture
So that we can ...
  • Describe the ways in which data can be captured
  • Describe the principles of operation of data input and output devices
    - barcode reader
    - digital camera
    - RFID
    - laser printer
  • Explain the difference between analogue and digital data and signals
  • Describe the principles of operation of analogue to digital (ADC) and digital to analogue (DAC) converters
  • State some application applications of ADCs
  • Discuss the ways in which manipulated data can be presented
  • Assess the suitability of input and output devices for different situations
  • Describe the applications of voice control
    - Direct communication with computers
    - The natural language interface
    - The issue of ambiguity
    - Voice commands and dictation

Activity 1 Methods of capturing data (75)

Data is captured for processing by computer by manual and automatic means.

Manual data capture methods
  • Data entry forms
  • Keyboard
  • Mouse
  • Barcode reader
  • Optical mark reader (OMR)
  • Magnetic stripe reader
  • Optical character recognition (OCR)
  • Touch screen
  • Chip and pin
  • CCD
 Automatic data capture methods (sensors)
  • Pressure
  • Fluid flow
  • Level
  • Proximity and distance
  • Biosensor
  • Image
  • Chemical / pH
  • Environmental

Task 1.1 Prezi!
Web browser
Prezi Account
Methods of capturing data.docx

First of all, create an account on Prezi - your teacher will show you how. You will then be given access to a pre-created Prezi which you should edit to include information about the multitude of data capture methods. Use the World Wide Web to help you if necessary.

I expect you to help to create the Prezi and use the information you and your peers have found to complete the worksheet 'Methods of capturing data'.

OUTCOME : Completed worksheet, Methods of Capturing Data.docx

There are two 'types' of data generated by manual and automatic input devices - analogue and digital. Even though the following examples are storage devices, the hardware used to retrieve the data is technically still reading data in one form or the other.

Click to view

Task 1.2 Datafication

The world is full of data. Representing real world objects as data is called datafication. There is plenty of work into this field of computer science for businesses. Big data, for instance, used datafication techniques to tease out meaning from the numbers.

Consider the list of objects which can be represented with data. You will be assigned one of the objects and a whiteboard and asked to consider how they can be represented as 'data'.

OUTCOME : Vague awareness of the ways in which real world objects can be datafied.

Activity 2 Principles of operation? (45)

There are lots of different devices which allow computer systems to interface with the outside world and I mean both input and output devices at this . For example (specifically) ...
  • Barcode reader
  • RFID tag reader
  • Digital camera
  • Laser printer

Task 2.1 Research - principles of operation
Course textbook
World Wide Web access if needed

The term 'principles of operation' simply means ...

... and you need to understand the 'principles of operation' for the three devices listed above. Using the course textbook and the WWW if necessary, write some notes and collect some research concerning these three devices. Don't worry about formatting and stuff, and how about using a pencil?

OUTCOME : A collection of notes describing how these devices work.

Activity 3 ADC / DAC (35)
 A Level Only

Inherently, humans are analogue. We live in an analogue world. We consume and generate analogue data. Computers, conversely, are digital devices composed of switches. Devices involved in the conversion between analogue and digital data are called Analogue to Digital Converters (ADC) and Digital to Analogue Converters (DAC). Bet you can't guess which device does what!

Click to enlarge

Task 3.1 You can do better than that!
Research tools
Creative brain waves

The diagram above shows where the two devices are used between a digital system and the outside world. It does not describe how they work. Nor does it give examples of what they are used for.

Using your favourite painting package, improve and complete the above diagram. I expect you to design and draw a diagram using suitable software which describes
  • the basic settings of the devices (i.e. where you find them)
  • the principles and operation of these two related devices
  • typical applications of both devices.
You may wish to use the following websites to help you (or you may not).

OUTCOME : A good quality diagram which you have designed which explains the setting, principles of operation and applications of these devices. You must try to explain how they work and where they are used, not just what they do.

Activity 4 Sensors and Actuators (45)

Watch the following video (try to stay awake) ...

Try to work out what's going on here and 'click' to visit the website (try not to be amazed) ...

Click to visit BBC news article

Task 4.1 What mate?
Awareness of the outside world

The relationship between a sensor and an actuator is a subtle and interdependent one.  Consider the humble automatic door sensor ... how does this fit with the following generic system?  Where is the sensor; where is the actuator?

Click to view larger

Your task is to identify 10 different situations where sensor / actuator pairs are used in the real world and prepare to play charades with the rest of the class!

OUTCOME : A fun game of charades where you learn about different sensor / actuator systems.

Activity 5 IPSO Facto (20)

All computer systems work on the principle that data is captured (input), changed in some way (processed), retained for future use (stored) and relayed back to the user in some form (output).
  • Input
  • Processing
  • Storage
  • Output
As long as you remember the acronym IPSO, you can't really go wrong!

Task 5.1 IPSO
Nothing specific

Data is gathered, processed, stored and returned to the user (input - processing - storage - output). For at least the situations stated below, identify the inputs, processing, storage and the output requirements For an extension, try to think about the 'format' of the output? What would it 'look like'?
  • An online poker game
  • A prototype interactive toilet
  • Pupil reports generator in a school
  • An automatic greenhouse ventilation system
  • An aircraft black box flight recorder

OUTCOME : Table or some other device which identifies the IPSO components of these systems.

Activity 6 Contemporary input devices (45) A Level Only

Moving away from the traditional keyboard and mouse is inevitable. Watch the following TED video ...

... and visit the following website.

Task 6.1 Applications
Web browser

With a particular emphasis on Voice Control, make some notes on contemporary input devices. For each device, give details of ...
  • It's applications
  • It's benefits
  • It's drawbacks
OUTCOME : A suitable list of contemporary input devices in your notes.

Extension Activities 

How about these?
  • This is a hard one. The Twyford VIP toilet is in the toilet museum in Hanley. Visit and take a picture of yourself next to the toilet. What sensors does it actually have? I expect you to glue in a copy of the photo into your assessment books and then write a list of the sensors that the toilet has.

  • Buy a domestic weather station from Amazon (or your favourite online shop). This one also has a weather forecasting function - cool.

  • With the development of cars which can drive themselves like the Google Self Driving Car, it's clear that modern cars are proper packed with sensors. Visit the website and spend a few hours reading through the information.

What's next?

Before you hand your book in for checking, make sure you have completed all the work required and that your book is tidy and organised. Your book will be checked to make sure it is complete and you will be given a spicy grade for effort.