The Role of Anthropometry and Biomechanics in Judging Others’ Maximum Horizontal Reach: Insights for Caregiver Robot Development

Our aim is to design caregiver robots to perceive others action capabilities, the same way humans perceive others action capabilities. We investigated what variables people pick up when perceiving an actor's maximum horizontal one degree-of freedom reach. Deconstructed point-light displays depicted either a short or a tall actor with markers either on their full body, upper body, lower body or only their ankles. The displays either showed the actors with movement or without movement (static). Participants adjusted an object to the distance they believed was the actor's maximum horizontal reach distance. The findings suggest people who are perceiving others’ maximum one-degree of freedom horizontal reach: (1) do not attend to actors' movements, and (2) attend to static aspects of the actors' upper bodies in relation to object distance. Findings from this study bring us closer to understanding what variables people pick up when perceiving others' maximum horizontal reach distances.