By Eugene le Roux, FSAIRAC, and Eamonn Ryan
The word ‘prototype’ is used frequently across engineering, manufacturing and technology fields – but not always with the precision it deserves.
The word ‘prototype’ is used frequently across engineering, manufacturing and technology fields – but not always with the precision it deserves. DC Studio | Freepik.com
In everyday discussions, a prototype may refer to anything from a sketch on a whiteboard, to an experimental piece of hardware, to a nearly completed product ready for full-scale production. This loose usage often creates confusion, particularly when large investments, technical risk, and client expectations are at stake.
In structured engineering environments, the development of a product proceeds through a clearly defined sequence of stages. Each stage has a purpose: to reduce technical, financial and functional risk until a product can confidently enter production. Understanding – and correctly naming – these stages is vital for communication, governance, budgeting and project success.
This article unpacks the logic of the development cycle, starting from early concept work and progressing through increasingly mature prototype stages. The goal is not only to clarify terminology, but also to ask whether shortcuts or out-of-sequence development can ever be justified – and what the consequences may be if they are.
From concept to design: when development truly begins
Every project begins with a concept supported by an agreed-upon value system: the justification for why the product should exist and what benefits it must deliver. Once this high-level intention is stabilised, structured engineering must take over. This is where the System Engineering Process (SEP) enters the picture.
The SEP pushes the project beyond ideas and into formalised design. Engineers examine packaging, mechanical constraints, electronic systems, producibility, ergonomics, interfacing with other equipment or platforms, and compliance with the client’s operational environment. At this point, the goal is not perfection but responsible completeness: the first design must be realistic, testable and aligned with the overall requirement.
This work results in what is known as an Advanced Development Model (ADM). The ADM is often misunderstood: it is not a final prototype ready for production. Instead, it is a carefully engineered model intended to:
- validate the design direction
- confirm the client’s functional satisfaction
- expose technical risks early
- allow meaningful practical testing
The client must remain aware that the ADM is still an early-stage prototype – reliable enough to test, but not yet reliable enough for full-scale operational use.
Iteration and refinement: achieving client satisfaction
The ADM naturally reveals design weaknesses, mismatches with the requirement, or integration challenges. Adjustments must be made, sometimes repeatedly, until the client agrees that the system meets expectations. Only when the ADM stage has fulfilled its purpose can the project advance.
But even this does not mean the product is ready for production. In fact, the next stage – covered in part two – is typically the most technically demanding and expensive.
