The Design-Engineering Process implies the matching of potential and specified Design-Ideas with quantified Performance-Requirements, quantified Resource-Requirements, and defined design and Condition-Constraints.
1. Planguage involves Design-Engineering. By contrast, conventional “design” activity (the kind of “design” often found in the literature and in practice), usually has a less Systematic, less quantified Process, using perhaps intuition, tradition, and more trial and Error, to determine satisfactory technology, and to determine Stakeholder satisfaction. It is characterized by naming objectives (for example, “better usability”), and naming designs (for example, “single Standard interface”), but not following up with quantified versions (that is, providing the information captured in Planguage, using such Parameters as Scale, Goal, Impact-Estimate and Meter).
2. The Design-Engineering Process can be subdivided into the following Sub-Processes:
a. design Requirements entry: all relevant Requirements to the design task are Complete, clear, quantified, testable, validated by Stakeholders, Quality-Controlled, reviewed, and have thus obtained formal entry into the Design-Process.
b. search and acquire candidate Design-Ideas and their expected performance and Cost Attributes, along with any Constraint threatening information. The search is based on matching design Attributes with Requirements, roughly
c. pick a reasonable set of Design-Ideas: this is done using Value-Decision Type of logic. It is done with regard to design Attribute Credibility, with regard to design Attribute uncertainty, and with regard to necessary Safety-Factor. When necessary, promising but uncertain, designs might need to be analysed in depth using experiments, research, Evolutionary implementation, and other devices to get more certain data about their Attributes.
d. Deliver designs Evolutionarily: the candidate set of Design-Ideas can then be delivered in an Evolutionary sequence, one or more at a step, in Priority sequence (high value to Cost first) measuring actual results of performance and costs, until targets are reached, or Budgets exceeded. Superfluous Design-Ideas, in terms of reaching targets within Constraints, can be kept in reserve for meeting improved target Levels. But they do not necessarily have to be implemented when agreed targets are in fact reached.
e. Post delivery design improvement: After a design is successfully implemented and delivered to some Stakeholders, there is still the possibility that it might be replaced later by a later emerging superior (value to Cost) design. This can happen Before major project completion, or After initial System or project launch.
This Concept entered by Diane O'Brien.