The term ‘design fixation’ refers to a phenomenon where designers unknowingly limit the space within which they search for solutions. In an attempt to study this phenomenon experimentally, researchers typically set participants open-ended design problems, prime them with an example solution and measure their performance through subjective metrics. This gives rise to various problems, including limited data capture and highly subjective evaluation of design behavior. To address these problems, we studied design fixation with a computer-based task inspired by psychological paradigms used to study ‘mental set’. The task consisted of a game-like activity requiring participants to design a bridge within a specified budget. The use of a digital environment facilitated continuous data capture during the design activities. The constrained task (and direct quantitative measures) permitted a more objective analysis of design performance, including the occurrence of fixation. The method used and the results obtained show an exciting alternative for studying design fixation experimentally and promote a wider exploration of the variety of design activities in which fixation might occur.