System engineering processes and methodologies are employed in the development of printing system robustness. Under the overarching umbrella of six sigma concepts, system robustness can be defined, developed, tested, measured, and verified. Designing robustness into a product at the systems level requires that the important system attributes are focused upon and made robust beginning in the subsystem development stage. Robustness and critical customer requirements are translated into physical functions, linked to contributing system and subsystem functions, and traced to critical dimensions on the parts. Six-sigma methodology as applied to parts manufacturing is not sufficient by itself. The application of the six sigma methodology at the system design level requires great discipline which is achieved by seemingly disconnected processes becoming linked under the umbrella of six sigma. These processes include require-ments management, FMECA's, problem identification and corrective action, DFx, Taguchi experiments applied at the system level, configuration management, additional systems test processes, noise maps, and limits definition. These elements are examined in a linked process that, applied with discipline and tenacity, results in a well-defined system, a well designed system, and a system that is verified as robust.
David G. Mabee, "System Robustness Achieved with System Engineering Methodologies" in Proc. IS&T Int'l Conf. on Digital Printing Technologies (NIP16), 2000, pp 307 - 311, https://doi.org/10.2352/ISSN.2169-4451.2000.16.1.art00079_1