نوآوری سیستماتیک و اصول اساسی در  TRIZ و TOC

Innovative developments in the design of product and manufacturing systems are often marked by simplicity, at least in retrospect, that has previously been shrouded by restrictive mental models or limited knowledge transfer. These innovative developments are often associated with the breaking of long established trade-off compromises, as in the paradigm shift associated with JIT & TQM, or the resolution of design contradictions, as in the case of the dual cyclone vacuum cleaner. The rate of change in technology and the commercial environment suggests the opportunity for innovative developments is accelerating, but what systematic support is there to guide this innovation process. This paper brings together two parallel, but independent theories on inventive problem solving; one in mechanical engineering, namely the Russian Theory of Inventive Problem Solving (TRIZ) and the other originating in manufacturing management as the Theory of Constraints (TOC). The term systematic innovation is used to describe the use of common underlying principles within these two approaches. The paper focuses on the significance of trade-off contradictions to innovation in these two fields and explores their relationship with manufacturing strategy development.

The concept of trade-offs, or conflicting performance parameters is a central feature of mechanical design where speed and efficiency, or strength and weight performance conflicts are readily acknowledged. These are typically well documented and the performance trade-offs are balanced in the design process to give the optimum for a particular application. What is less well known is the significance of these contradictions in the innovation process. The practice of using trade-off parameters as a focus for systematic innovation in mechanical design has only recently emerged from Russia under the name of TRIZ (The Theory of Inventive Problem Solving), but it is already attracting significant industrial interest [1]. In the field of manufacturing it is over 30 years since Skinner [2] used the concept of mechanical design trade-offs to help acknowledge and manage conflicting performance parameters associated with manufacturing. This extract from his seminal work illustrates the mechanical analogy. For instance, no one today can design a 500 passenger plane that can land on a carrier and also break the sound barrier. Much the same is true of manufacturing. The variables of cost, time, technological constraints, and customer satisfaction place limits on what management can do, force compromises, and demand an explicit recognition of a multitude of trade-offs and choices. [2] From this and subsequent papers the strategic trade-offs associated with manufacturing investment and decision-making became explicitly recognised. The term ‘manufacturing strategy’ emerged with a new awareness of performance conflicts and the need to make strategic choices between competitive criteria, such as speed and efficiency, or quality and cost. Since then the debate has moved on and some of the originally cited trade-offs are acknowledged to have been all but eliminated in certain sectors, with the application of developments such as JIT and TQM, now often cited as heralding a new manufacturing paradigm [3]. As a consequence some would argue the trade-off analogy with mechanical design is no longer relevant [4]. Others argue that trade-offs change [5], [6] and [7], as with mechanical systems, but the perceived role of the trade-off concept is largely limited to one of acknowledging their existence, so that the negative impact can be minimised. This paper aims to shed new light on this debate by exploring the deeper significance of trade-offs in mechanical design before linking the analogy to organisational improvement and innovative developments in manufacturing. The thesis of this paper is that the concept of performance contradictions has much more to offer than that has been widely acknowledged to date, not only in the design of artefacts but also manufacturing strategy. The paper will outline the TRIZ and Theory of Constraints (TOC) perspectives on performance contradictions, demonstrating the common underlying principles, before exploring the broader significance of trade-offs in manufacturing.

Common aspects and distinctions of TOC and TRIZ: 1. Both subordinate the importance of reducing cost in improving ‘Ideality’ and ‘Value added productivity’. 2. Both consider trade-off situations, in the form of conflicts and contradictions, as key to purpose focused improvement. 3. Both claim that the resolution of contradictions and conflicts can be structured. 4. The TRIZ concept of physical contradictions and the TOC EvCs both centre on explicitly defined contradictions and the EvC diagram provides a means of practical integration. 5. Whereas the TRIZ solution systems apply principles to break the contradiction directly the TOC approach focuses on challenging the mental models underpinning the perceived conflict. The term systematic innovation has been used to convey the common underlying principles embedded in these two industry based approaches to focused improvement. Both approaches view the identification and resolution of performance contradictions as key to the long-term value added improvement of a system and the tools used to break the conflict have been shown to be highly complementary. The trade-off analogy associated with manufacturing strategy is still valid, but needs to be conceptually developed to encompass the importance of not only acknowledging trade-offs in managing the inherent conflict, but using the conflict as a focus for innovation. It is suggested that the systematic innovation concepts and tools embedded in TRIZ and TOC enhance the traditional manufacturing strategy thinking and the EvC diagram can be used to practically integrate their use.