Description
The prior knowledge base in design and engineering, as with nearly all domains, is extensive.We have been designing and producing a wide range of sophisticated machines and systems for centuries. The detailed design of many machine elements and types of machinery has been codified and significant expertise is readily available. Just knowing that someone else has successfully produced a product or system can act as inspiration or provide direction for a similar product or the design of a subsystem that uses associated technology, or needs to have comparable functions.
Many attempts have been made at defining design. The word can be used as a verb or noun, describing the process and the outcome of design, respectively. Referring to design as a process, it can be considered to include all the activities of market assessment and user requirements, specification, concept generation and idea development, embodiment of details, risk mitigation, consideration of manufacture and production, and implementation. Referring to design as a noun, the term is commonly used to describe an artifact such as a vehicle, item of fashion or other product, with the associated features and merits. This may include description or commentary on aesthetic, ergonomic, and technical features. In this book, an inclusive approach to design is used with consideration of a range of functionalities ranging from technical, aesthetic, social, economic, and latent. Design is considered to be the process of conceiving, developing, and realizing products, artifacts, processes, systems, services, and experiences with the aim of fulfilling identified or perceived needs or desires typically working within defined or negotiated constraints.
Engineering involves significant overlap with design and, indeed, it is often difficult to make a clear distinction. A common distinction is the use of quantitative analysis in engineering to aid and inform the development, simulation, testing, and refinement of a system or product. Engineering can thus be considered to be the application of scientific and mathematic principles in combination with professional and domain knowledge, in order to design, develop, and deliver artifacts, products, and systems to realize a societal, commercial, or organization requirement or opportunity. Mechanical engineering refers to the use of engineering processes to applications of a mechanical nature, typically involving moving components or energy processes. Mechanical engineering heavily relies on the engineering sciences of thermodynamics and mechanics, often integrated through design, in the development and refinement of a solution for a specific requirement. The title for this book comes from the blend of mechanical and design engineering, the latter with its heritage in the on-going collaborations between Imperial College London and the Royal College of Art through the Innovation Design Engineering double masters, of which I have the honor of being joint course director.
The detailed design of a wide range of machine elements that are commonly used in mechanisms and machines has been the focus of attention of many companies and research groups around the world. Examples of such machine elements include bearings, shafts, gears, belts, chains, clutches, brakes, seals, and springs. Many of these are available as stock items or standardized components that are produced by a range of companies, enabling the engineer or designer to focus attention on selection of appropriate stock items and the integration of these within the application of interest, rather than having to repeat the development of previous knowledge. For other machine elements such as shafts, some clutches and brakes, and seals, their design can take advantage of prior knowledge and design guidelines.
Industry is typically concerned with the development of return for investors, or owners, within their specific product or service sector. A wide range of approaches is employed to manage the development and delivery process for new products and systems, or the manufacture and production, and delivery, of artifacts and services. Many models and approaches for the design process are employed in industry and area often bespoke to the particular organization concerned. Studies across a range of industries have identified some commonality in approach and a number of models have been proposed as representative of a standardized approach to design, and the management of design. A selection of these is presented in Chapter 1, providing an overview of typical approaches to the design process and its management.