Modularity and Design Reuse

Modular design and design reuse enable more rapid development of new products, new versions, or enhancements of existing products without having to incur the time and expense of designing and manufacturing from “scratch” each time. For example, existing module designs can be used as a starting point to upgrade or improve a module function or technology, or an existing module can be used essentially as-is where a module function or technology does not need to be changed.

In addition, companies can use a module design approach to insert a newly developed module with additional functionality or new technology into a system without having to risk interfering with the rest of the system. Modular design and design reuse enable and encourage efficient innovation, both within existing modules and in surrounding components and products, because discrete or even wide-ranging product alterations can be made while greatly reducing (and potentially eliminating) the risk of any deleterious, cascading impacts on the entire product or product line that are time consuming to detect, debug, and remove prior to product launch. Design reuse is not limited to the physical manifestation of a design, but also to the logical representation such as specifications, drawings, schematics, software code, and test programs.

Even in a universe where a design can and does change relatively late in the development process, all else being equal, a modular design is frequently going to be easier to seamlessly replace, and such replacement runs a smaller chance of creating interface or interconnect problems or other design errors.

Utilizing modular design and design reuse typically enhances a company’s ability to efficiently and effectively develop future products and product designs. For instance, with design reuse, engineers can often focus their development efforts on the specific areas of a product where they seek to make technical improvements, with reduced complexity, because other components in the product that do not need to be modified or improved can be seamlessly implemented from prior product designs without as much, if any, required validation.

Modular design and design reuse are important tools that often enable companies in fast-moving industries to remain competitive and meet their (and their customers’) product and scheduling demands. The greater the complexity of a product, the more time and expense it will typically take to develop that product from scratch or to make changes to its design. Modular design and design reuse thus present makers of complex products with critically important techniques to manage these complexities.

Design reuse is an important tool that enables companies to focus more of their design efforts, including time and resources, on designing “better future products.” With modular design, companies can further focus their design efforts on the modules containing the specific components or features that they want to upgrade or replace while reusing the modules that do not need to be upgraded or replaced without having to build them from scratch. And design reuse often reduces the time and cost required to develop a new product. Time is often reduced by having well-defined specifications for modules and their interfaces that then allow the modules to be developed in parallel and relatively independently. Use of existing modules often avoids the effort and cost to develop a particular function.

Modularity and design reuse also can benefit the quality of a product. By using best practices such as modularity and design reuse, once a problem is identified and solved, it will usually stay solved. And then that validated module can be implemented in future designs or product iterations, without having to be built from scratch, with significantly reduced risk of further error, and with little or no risk of repeating the same error as more or different engineers are engaged in future product improvements. With proper utilization of modularity and design reuse, there are generally going to be fewer and fewer negative “surprises” with each new product iteration.

Design reuse is not limited to being able to literally reuse full parts exactly “as is,” but applies much more broadly and more usefully to the ability to reuse technology and features within products such that, for example, one does not need to create an interconnect from scratch.

Modularity, Design Reuse and Schedule

Project management is focused on balancing three factors: time, cost, and project (product development) scope. Often these project parameters are referred to in project management circles as the “iron triangle”. The concept behind this model is that typically a company can optimize one or two of these parameters on a particular project, but it is difficult to optimize all three parameters simultaneously. There are various best practices companies can use in their effort to optimize these three parameters in a particular project.

The modularity and design reuse practices discussed in my reports directly bear on a company’s product development schedule. For example, one of the benefits of modularity and design reuse is that development programs that normally require longer schedules can often be accomplished in less time and using fewer resources. A “robust feature set” can often be accomplished through techniques related to modularity and design reuse without necessitating a materially longer schedule (or, at least, on a shorter schedule than would otherwise be required without the benefits of modularity and design reuse). This is because often times 1) project scope can be reduced to the extent that design reuse occurs and 2) well-defined module requirements allow development of individual modules to proceed in parallel and relatively independently until final integration and validation. Thus, oftentimes the trade-offs can be reduced or eliminated in significant part through modularity and design reuse.

A great advantage of modular design is that development of any new modules can proceed largely in parallel, saving significant time as compared to an integrative approach to design. Sometimes, there may be slight additional costs on the backend of development to properly document and “package” the modular design of a new module. However, these potential costs are usually minor and are more than recouped (often significantly) with the reduced development time and faster time-to-market. Further, this modular design approach is often required to support sets of different products within a product family.

Modularity, Design Reuse, and Design Cost

The fact that modularity and design reuse are often used to reduce such “design costs,” and those savings can be significant. Generally, modular design enables design reuse, and design reuse reduces the non-recurring development effort of specification, development, testing, and validation.

Development costs will be lower when using properly implemented techniques for reuse and modularity as compared to not using reuse and modularity. For instance, if you consider the modular design approach, it is important on the front end to define the requirements and scope of each module and the interface specifications. This definition may take some additional time and resource cost versus an integrative design, but if using industry standards or well-defined interface requirements, there would likely be little to no additional time and resource cost required. In fact, the use of an interface or interconnect standard would likely provide significant time and cost advantages for modular design with both the development of new modules as well the reuse of existing modules.

Validation and test costs can often be minimized through modularity and design reuse because modules that have already been validated and tested from a previous product can often be reused in future products with reduced validation and testing effort. This typically reduces costs due to the enormous amount of design verification and validation undertaken as part of the design effort – the existence of modules that can be reused typically reduces the overall amount of development effort and cost and the amount of testing and validation effort cost that is required for a subsequent product that reuses the modules.

One benefit of modularity and design reuse is that they often reduce opportunities for, and likelihood of, errors. And errors can be quite costly.

Modularity, Design Reuse, and Product Cost

Modularity and design reuse can have a significant positive impact on development (reduced cost and schedule and increased quality), as well as reduce production cost once a design is put into production. This is the result of producing greater volumes of these standardized modules.

Modularity and Product Variants

Modularity and design reuse often enable more robust feature content, developed in less time and at lower cost. Among other things, with modularity and design reuse, engineers can focus more of their time and resources on developing new features to create new product variants without having to spend as many of those resources on rebuilding old features that have already been successfully modularized and validated. They can further incorporate and reuse new features and feature sets developed by completely separate engineering teams that they would not otherwise be able to independently develop or reliably incorporate within their project constraints. Further, modularity and design reuse are often a critically important or even a necessary basis for product families. As a general matter, it would be exceedingly difficult to economically offer many versions of a product without modularity and design reuse.

Companies situated in dynamic markets often get the greatest benefits from use of modularity and design reuse. Among other things, such technologies often enable companies in dynamic, fast-moving markets to get maximum mileage out of their resources by using foundational building blocks (designed to be modularized or reused) to more rapidly, and at less expense, develop new products, develop product variants, or develop customized products for particular customers.

In implementing product roadmaps, it is often more cost efficient and less time consuming when the new designs are built from common building blocks rather than being developed from scratch each time. Where companies forego modularity and design reuse, particularly with complex products, an enormous amount of time and resources are often spent on redeveloping static components or assemblies, and retesting interconnects, that would be materially reduced or in some cases eliminated if they were to start from a modular design.

Modular Design vs. Integrative Design

To the extent companies can implement technologies and procedures to reduce the overall impact of such unexpected twists and turns, they will typically be in a better position financially and competitively all else being equal. Generally, a company that foregoes a modular design approach will implement some form of an “integrative design” approach, where the different individual components in a product are designed to have tightly interactive relationships, with lots of connecting individual parts. Among other things, this would make the development of product families more difficult. While an integrative design approach can be used at times to optimize product design, the slightest change or bug can have a severe impact on the entire project. A modular design, on the other hand, can more effectively tolerate changes throughout the development process by isolating the impact of changes to one or a few modules.