1. Digital media & interaction design
LECTURE 2

2. Lecture 2 : User-Centered Design

3. LECTURE OUTLINE Design process User centered design (UCD)
The important of
Visibility
Mapping
Affordances
Feedback
Constant
Design process
User centered design (UCD)
Interaction Design Principles

4. The important of :
Visibility
Mapping
Affordances
Feedback
Constant

5. Make important things and operation visible
VISIBILITY
One of the most important aspects of design – interface must have visible features, inferring the right messages to us
Make important things and operation visible
Make important things clearly
Make them easy to find   

6. MAPPINGS:
The link between what you want to do and what is perceived possible. It is the relationship between moving a control, and the results in the real world

7. AFFORDANCES:
The perceived and actual properties of the thing, primarily those fundamental properties that determine just how the thing could possibly be used
(e.g. a chair affords sitting; glass affords seeing through, breaking; wood affords solidity, opacity, support, carving)
Affordances provide us clues on how to operate a device

8. (check box used to be rectangle)
Constant:
limits to the perceived operation of a device or interface :size, color and pattern
Ex:
( bank website )
(check box used to be rectangle)

9. Feedback:
Sending information back to the user about what action has actually been done and what result was accomplished

10. Design for Error
Use all of the 4 to prevent error , and still make the system robust against errors

11. Requirements Analysis
1-The Waterfall Model
Design Process
HCI first model to be used in the design process was the Waterfall model
Requirements Analysis
Design
Implementation
Testing
Maintenance

12. Requirements Analysis
2-The Iterative waterfall model
This model lacked any research about the user. It did not talk about people, the user,, so it is clear that here they studied in isolation.
Requirements Analysis
Design
Implementation
Testing
Maintenance
The next issue is that testing is a functional task, but evaluating would be trying the piece in the real world
Iteration

13. Requirement specification
The newer model for HCI. This was a development from the water fall cycle. So this new model had evaluation now in its process. before evolving onto the next level in the design process, you must evaluate and reflect on one part of the process before moving onto the next phase within the project design .Also here we have prototyping .
3-The Star Life Cycle
Evaluation
Task Analysis
Implementation
Requirement specification
Prototyping
Formal Design

14. 4-The User Center Design process
This new model is about understanding the user. It has evolved on from the previous model of task analysis, to understand what is going on with the user,
4-The User Center Design process
Prototyping
Understand User
Draw
Requirements
Evaluate
Iteration
The UCD process is an iterative process, where design and evaluation steps are built in from the first stage of projects, through implementation.
The key concept to keep in mind is this idea of constant evaluation throughout

15. What is User-Centered Design ?
In UCD, all "development proceeds with the user as the center of focus."
-Jeffrey Rubin(Author- Handbook of Usability Testing)
User-centered design process (UCD) is also called human-centred design process.
"Human-centred design is an approach to interactive system development that focuses specifically on making systems usable. It is a multi-disciplinary activity.”
-Human centered design processes for interactive systems, ISO (1999),

16. User-Centered Design
"User-Centered Design (UCD) is a user interface design process that focuses on usability goals, user characteristics, environment, tasks, and workflow in the design of an interface. UCD follows a series of well-defined methods and techniques for analysis, design, and evaluation of mainstream hardware, software, and web interfaces.The UCD process is an iterative process, where design and evaluation steps are built in from the first stage of projects, through implementation.” (Shawn Lawton Henry and Mary Martinson, Accessibility in User-Centered Design)

17. The ISO standard describes 6 key principles that will ensure a design is user centered:
The design is based upon an explicit understanding of users, tasks and environments.
Users are involved throughout design and development.
The design is driven and refined by user-centered evaluation.
The process is iterative.
The design addresses the whole user experience.
The design team includes multidisciplinary skills and perspectives.

18. Design Should:
Make it easy to determine what actions are possible at any moment
Make things visible, including the conceptual model of the system, the alternative actions, and the results of actions.
Make it easy to evaluate the current state of the system
Follow natural mappings between intentions and the required actions; between actions and the resulting effect; between the information that is visible and the interpretation of the system state

19. Principles for making difficult tasks simple ones:
Principles for making difficult tasks simple ones:
Use both knowledge in the world and knowledge in the head
Simplify the structure of tasks
Make things visible:  bridge the gulfs of Execution and Evaluation
Get the mappings right
Exploit the power of constraints, both natural and artificial
Design for error
When all else fails, standardize

20. bibliographic reference list:
Interaction Design: Beyond Human-Computer Interaction  by Helen Sharp