- Table of contents
- Constraints
Constraints¶
Constraints are limits on design freedom. (Dieter & Schemidt, 2007, p.92) In general, constraints may be thought of as boundaries to a project. Ulrich and Eppinger, in their book "Product Design and Development", identify some constrains that XEROX applied to their Lakes project. (Ulrich & Eppinger, 2012, pp.68-69)
There may be multiple sets of constraints. For example, one set of constraints may apply to the design process, another to the manufacturing / production phase and a third set may apply once the item has been shipped / distributed / sent out for use.
The categories below identify some of the possible areas where constraints may exist.
Safety¶
There are regulatory bodies such as OSHA that may impose constraints through their various rules. The existence of some of these rules may generate specific design requirements which would be documented separately from this constraint.
Manufacturing / Fabrication¶
As parts or products are created, there may be constraints. These may relate to the manufacturing processes available or to the range of materials available. For example if a company wishes to produce metal products, they must have the processes appropriate for the types of metal they plan to use. Thus their capabilities becomes a constraint. They can, of course, address this by simply adding the necessary processes or by outsourcing part of the work.
Time / Schedule / Manpower Resources¶
Projects do not have infinite amounts of time available to them! There are typically specific milestones that must be accomplished by specific dates. Teams also do not have unlimited human resources with which to accomplish the work. All of these form constraints to a project and must be managed properly for the success of the project.
Environmental / Sustainability¶
Additional constraints may come from our ever more conscious awareness of the environment and a corresponding need to protect it. There may be constraints as to what emissions a factory can emit or how much is permitted. Certain emissions may be banned completely for new facilities but 'grandfathered in' for older existing ones.
Environmental concerns extend beyond the earth itself. Additional environments include home / office / factory or other special locations. These may each have differing constraints on what may or may not be allowed / permitted / desired. These too should be documented as needed.
Certain projects might have a focus on sustainability related issues. Some companies are currently looking at improving their sustainability metrics and may set certain constraints related to this.
Company / Client Mandates¶
A given project may have directives from the company or Client that serve as constraints. For example, it may be a company policy to avoid use of a competitor's product whenever the company makes a similar product. Or a company may be developing a new technology and this dictate that the solution must employ that specific technology.
Budget¶
As with time and human resources, projects do not have unlimited financial resources. Your project's budget is this a constraint. It must be noted that the budgets that may apply to the design process are likely to be different from those that apply to the manufacturing / fabrication phase.
Bibliography¶
Dieter, G. E., & Schemidt, L. C. (2007). Engineerig Design (4th ed.). Boston: McGraw-Hill Higer Education.
Ulrich, K. T., & Eppinger, S. D. (2012). Product Design and Development (5th ed.) New York: McGraw-Hill Irwin.