Chapter 7 Interactive Design and Prototyping Human Performance Engineering Robert W. Bailey, Ph.D. Third Edition

General Activities Identify user needs- What the system will do Make numerous design decisions- How Implement the design- Programming Test- Software and Hardware

System Design Methodologies Structured Design Method Iterative Prototyping Combination of the two Very large systems, with many designers involved, require control that comes from ??

2 Types of Software Prototyping Tools Production prototyping –Design and develop an entire system. RAD- Prototype becomes actual system. Rapid prototyping- Quickly try out various decisions and ideas. Create, Change, Create. Ensure best possible usability before coding begins.

Results of good prototypes??????

Iteration

3 Components can be prototyped  Functionality  User Interface  Physical Characteristics

High-Fidelity Prototype= When a prototype closely matches the real system. Production Prototypes – Negatives ????

Rapid Prototyping Components 1.A way to design and develop windows and screens. 2.A way to link together fields, windows, and screens. 3.A run-time program. 4.A means of conducting usability studies. 5.A means of capturing or “Photoing” existing windows or screens. 6.A way of printing the results.

Prototype should be WYSIWYG. Prototyping by users: Positives and Negatives?

Limitations of Prototyping by Users: May take 6 months to deliver May not perform as fast as prototype May not be able to deliver

Usability Requirements????? Measuring User Performance:?????

3 Stages for the Design and Development of User Interfaces: 1.Analyze and define product 2.Design and develop user interface 3.Design and develop facilitators

*The earlier we begin making user interface decisions, the better will be the user interface.* To the user, the interface is the system.