See Sort Sketch: Pen and Paper Technique from Research to Design

Using traditional techniques to research. Design research was originally constituted as primarily research into the process of design, developing from work in design methods, but the concept has been expanded to include research embedded within the process of design, including work concerned with the context of designing and researchbased design practice. The concept retains a sense of generality, aimed at understanding and improving design processes and practices quite broadly, rather than developing domainspecific knowledge within any professional field of design.