A comparative study of safety zone visualisations for virtual and physical robot arms using augmented reality

The use of robot arms in various industrial settings has changed the way tasks are completed. However, safety concerns for both humans and robots in these collaborative environments remain a critical challenge. Traditional approaches to visualising safety zones, including physical barriers and warning signs, may not always be effective in dynamic environments or where multiple robots and humans are working simultaneously. Mixed reality technologies offer dynamic and intuitive visualisations of safety zones in real time, with the potential to overcome these limitations. In this study, we compare the effectiveness of safety zone visualisations in virtual and real robot arm environments using the Microsoft HoloLens 2. We tested our system with a collaborative pick-and-place application that mimics a real manufacturing scenario in an industrial robot cell. We investigated the impact of safety zone shape, size, and appearance in this application. Visualisations that used virtual cage bars were found to be the most preferred safety zone configuration for a real robot arm. However, the results for this aspect were mixed for a virtual robot arm experiment. These results raise the question of whether or not safety visualisations can initially be tested in a virtual scenario and the results transferred to a real robot arm scenario, which has implications for the testing of trust and safety in human–robot collaboration environments.