The Fundamental Principles of HCI Design
There are two fundamental principles that we need to be aware of when designing an interface for HCI. The two important fundamental principles are the perception and the information processing.
Perception-Perceptions are considered in different ways depending on between the developer and the user, where it is possible that the developer may not be the same person as the designer therefore the client’s needs is not fully aware even though the client may not be the user. The user may not also be fully aware of the Graphical User Interface details for the colour, pattern and objects.
- Colour: Colour is very important when designing GUIs, as with how the colours are used on the GUIs the colours it always represents something. The colours also would have to be considered depending on the users’ needs, as every possible type of user can be affected with the use of colours in different ways, especially for the users who have specific medical conditions. Microsoft office use grey as their main colour and they use blue for their drop down lists and titles. However many people would think that them two colours are boring and dull, although if it was changed to another colour such as bright red it would be uncomfortable on peoples eyes, though people are affected differently by various colours. People with dyslexia are affected by certain colours differently, they may prefer using yellow or any other colour.
Luminance: To display with the best designs is to use the luminance contrasts, the colours are paired up in this form, ‘red-green’, ‘yellow-blue’, and ‘black-white’.
Pop up effects: The pop out effect uses colour combinations to make symbols and images stand out on different backgrounds. When you are designing interfaces you have to make sure they are fit for the purpose, if you use too much colour it could reduce the professionalism of it.
Patterns: We use alot of patterns in HCI, we do this because it will keep your interface consistent and symmetrical. This will make your interface easier to use as they will remember where everything is and it will make them feel more comfortable. In the template section there are a number 0f things such as colours, format, layout and common groupings(menus,options).Objects: Separate objects are used to build components of a GUI or any other type of image display. Objects are seen in hierarchial system, this means the images are layered. It is very important knowing the order of the objects, if the images are put in the wrong order the user would see an imcomplete object.
Positioning: When positioning objects it is vital as it has to be considered to be included on the interface. If the object is not positioned accurately the user maybe affected from the objects not being visible as it may be hidden behind the main interface.
Behaviour Models- Behaviour models predict in which way an interface or user will behave. There are two behaviour models these are predictive models and descriptive models. Predictive Models: Predictive Models are used to compare and evaluate motor behaviour in the design of interfaces and systems.
Descriptive Models: Descriptive Models are a model of human movement and they are primarily used in human computer interaction and ergonomics that predicts that the time required to rapidly move to a target area is a function of the distance to the target and the size of the target.
Information Processing- Information processing is how information is processed or how it will be processed and how fast it is done.
- Human as a component: One of the key variables in HCI design is the human end user. However this task can be very difficult as it recognises peoples needs and expectations. A risk assessment is one way to analyse task steps needed for the end user.
- Human information processing: Human information processing is a principle in a theory that humans work like computers do. The brain and mind are the central processing unit which thinks, calculates and produces the output. The output devices are an action you perform using your body or an action you perform on a computer.
Specialist Interfaces- These designs include inputs and outputs for people with different impairments for example:
People who are visually impaired: They would need in addition to normal computer equipment they need special electronic equipment designed to be used by people with a visual impairment. This includes purpose made portable Braille computers, Braille input and output devices for standard computers and speech activation.
People who are visually impaired: They would need in addition to normal computer equipment they need special electronic equipment designed to be used by people with a visual impairment. This includes purpose made portable Braille computers, Braille input and output devices for standard computers and speech activation.
People who are orally impaired (speech problems)- People with oral impairments would prefer data input though keyboards and a mouse. They can also use certain special equipment such as a text to voice program or portable device.
People who are aurally impaired (hearing problems)- People with hearing problems would require interfaces to be visual instead of things being spoken aloud.
People who are physically impaired)- People with restricted physical movement often find use of a standard keyboard may not be possible but a specially adapted device mouse and keyboard may be more suitable.
