A Design-Problem is expressed as a Requirement-Specification that includes a “complete set” of valid targets and Constraints, together with updated information about the degree of satisfaction in the design or the implementation.

Alternative Names

Concept Number: *654
English Master: Design Problem
Synonyms, Variations & Acronyms: Design-Target Residual-System-Requirements Design-Gap Gap


A Design-Problem is the “set of gaps” (to meet required Levels) that remain to be designed for.




Engineering Concept


O------------~lt~-----------|=====The Gap===>------->

''The progress from the Benchmark (~lt~) to the current Level (|) leaves a Gap (==) to the Target (>). This illustration brings in the idea that there has been some progress (“~lt~-------|”) since initial Requirements were specified (“-~lt~-”) , in delivering some degree of Requirements target satisfaction using some Design-Ideas. The gap (“|====>” represents the remaining problem with this particular dimension of a Requirement''.


Note 1. We assume that the designer does not yet contain or have access to sufficient design Solutions to reach all their targets, within all specified Constraints, otherwise there would be no “problem” remaining.

Note 2. Under Evolutionary-Project-Management, the Design-Problem will Evolve as the project progresses. Each new Design-Idea, when implemented at an Evo-Step, will have a set of cumulative Impacts on different Requirements. The then remaining set of unsatisfied Requirements (“gaps”) become the new “Design-Problem”.

Note 3.
On the notion of a “complete set” of Requirements in Problem-Definition.
A simplified Design-Problem could be formulated using one or a few Requirements or Constraints, just to see if that were technically or economically feasible at all. But the real Design-Problem must be solved using all valid Requirements. If this is impossible, then perhaps some of the Requirements need to be realistically “relaxed” to allow some of the others to be satisfied at all.

Short form: Problem.



(The gap between < a Past and > a target is an iconic symbol of a Design-Problem)






This Concept entered by Diane O'Brien.

Created by system. Last Modification: Thursday 11 of July, 2019 18:00:19 CEST by Admin (Kai).

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