Abstract Design fixation commonly plagues designers during conceptual design. Being fixated on a concept ultimately leads to less exploration of the solution space, wasted time, and less creativity. Therefore, engineering design researchers have given significant attention to measuring and alleviating design fixation in order to unlock highly innovative ideas. While researchers have long studied design fixation in open-ended tasks, largely using subjective means to evaluate the similarity of designers' solutions to example solutions, less focus has been paid to constrained design problems. A feature of many constrained design tasks is that they often involve computer-based design tools, enabling the use of more objective metrics and analyses of fixation. Unfortunately, this feature of computer-based design tools remains relatively under-explored. In this work, a six-step generalized methodology is introduced for objectively evaluating design fixation in computer-based constrained design tasks. A key feature of the methodology is the definition of similarity metrics which enables direct and quantifiable comparison between any two designs with respect to relevant design variables. We demonstrate the methodology on a drone design task using an adapted version of the HyForm Experimental Research Platform. Objective design fixation data are analyzed using quantitative metrics to understand how well participants explore the solution space and to what extent they fixate on both an example provided to them and their own initial designs--two fixation types commonly studied in open-ended design. Finally, implications of the methodology for product design and fixation interventions are discussed.
Hunter et al. (2026) studied this question.