The TRENDS project will implement the “Spiral Model of Software Development and Enhancement” for its design process (Boehm, 1988). This methodological and risk management approach has been chosen as it proved to be truly appropriate for R&D project dealing with the design of interactive systems. Thus, TRENDS design process will be based upon the hypothesis that a given operational circumstance can be improved through the development of appropriate systems. The spiral ends if the system cannot be improved any further. Individual cycles through the spiral follow a waterfall approach.

At first, the following sequence of steps will be carried out for each R&D critical phase of the TRENDS project:
  • Objectives: Statement of the objectives for the given cycle
  • Constraints: Statement of the known constraints on development within a given cycle
  • Possible courses of action (alternatives): Outline of the alternative approaches available given the cycle’s objectives and constraints
  • Risks: Overview of any risks, including hardware, software, usability and project management related, for the given cycle
  • Risk resolution: Description of the methods used to reduce risks, including prototyping, user tests, cost plans, etc.


In the TRENDS project four different prototypes will be tested by the end-users:

Prototype 1 (M12): Prototype 1 is the interface prototype. This prototype is a PPT version without any algorithmic development.
Prototype 2 (M18): Prototype 2 is the first version of the components prototype. As components, it includes the User interface of text and image search, the User interface for ambience and pallets, and the User interface for the Meta Search Engine.
Prototype 3 (M24): Prototype 3 is the full prototype integrating the previous components.
Prototype 4 (M30): Prototype 4 is the operational prototype: it is the final version of the software..