The design firm IDEO uses a design process that has drawn much attention. You can view their company website here: ideo.com or look at the materials below for more information and/or inspiration.
"Materials are the stuff of design. From the very beginning of human history, materials have been taken from the natural world and shaped, modified, and adapted for everything from primitive tools to modern electronics. This renowned book by noted materials engineering author Mike Ashby and Industrial designer, Kara Johnson, explores the role of materials and materials processing in product design, with a particular emphasis on creating both desired aesthetics and functionality." 2nd edition
Engineering Design Process and Innovation Resources
Yentzer, David A., and Ray Clark. "News and Information: The “Hierarchy of Needs” Screening Process: A Method for Rapid Development and Rationalization of Reasonable Alternatives." Environmental Practice 8, no. 4 (2006): 215-17.
"Summary: What is design thinking and why should you care? History and background plus a quick overview and visualization of 6 phases of the design thinking process. Approaching problem solving with a hands-on, user-centric mindset leads to innovation, and innovation can lead to differentiation and a competitive advantage."