Modularity and Design Reuse Benefits

Modular design is a development approach that breaks a product or system into the functions that it requires and develops a technical solution or module to perform each function independently. Modularity enables design reuse which offers a number of benefits. While modular design typically requires more effort upfront to establish well-defined design rules and interfaces between the product’s modules, once such rules are defined, these modules can often be developed independently and then seamlessly assembled to create a product or multiple products rapidly. Modular design typically reduces development time as well as development costs, if not for the first product, then for subsequent products using these modules.

There are many potential benefits of modular design and design reuse to companies in many industries. These may include:

  1. Design reuse and modular design often reduce development time and improve time-to-market.  For example, modules do not have to be redesigned for each use; they just have to be integrated into the larger system.  Such acceleration of product development times resulting from design reuse and modular design is significant.

  2. Design reuse and modular design often reduce the non-recurring development expense of the development project.  For example, through design reuse, the effort to develop equivalent functions and integrate subsystems is largely avoided; the primary effort required is validation.  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.

  3. Design reuse often reduces the risk of customer rejection or problems related to interoperability of the components with customers’ products.  For example, if a module or component worked well for a customer for years, reusing that module or component typically increases customer acceptance and speeds customer time-to-market, by, among other things, reducing the time required for customer integration and functionality testing.

  4. Design reuse often reduces the overall size and complexity of the development project.  This often avoids errors and uncertainty with use of a proven design.  This makes project management and coordination easier and it reduces project risk.  Project risk ultimately gets translated back into added development cost and added development time.  Complexity can also lead to less optimal design.  The more complex a system is, the more difficult it is for a person to understand the overall system and to understand the implications of each design decision.  Also, more alternatives need to be explored to find an optimal solution.  By breaking the complex system down into sub-systems or modules that are relatively independent, this helps to overcome the complexity issue, allows people to better understand the implications of each design decision, and allows each smaller sub-problem to be solved with fewer alternatives to explore.  This is the objective with modular design.

  5. Modules can be technically upgraded independently without negatively affecting overall system functionality.  For example, a product can be upgraded by just upgrading one or more modules of a product and leaving the rest of the product unchanged.  Or in creating a new version of a product, the designer can replace an older module with a new, more technologically advanced module, without interfering with the rest of the system and its functionality.

  6. Modular design often enables development of a greater range of product variants.  A car is an example of this principle.  Automotive companies develop a “baseline” version of a vehicle and offer variants such as a “luxury” or “sport” version.  A customer who selects a “sport” package may pay more money to replace the basic tires with racing tires, replace the standard suspension with a tighter suspension, and add in a dashboard navigation system.  These additional components can usually be easily and seamlessly integrated into the car at the customer’s request without interfering with the rest of the car’s operation and functionality.

  7. Design reuse and modular design can reduce the likelihood of errors during the product development process.  For example, modular design can allow for greater reuse of modules or components that have already been tested or validated.  To the extent that these proven modules are used, this typically reduces the overall likelihood of a problem with the product.  And the more complex a product or system, the greater the risk of an unidentified error if all of the system’s subsystems and modules are newly developed (vs. reused).  The more complex a system is, the greater the amount of verification and validation that needs to be done at component, subsystem and system levels.