Human perceptions of warmth and competence in swarm robot behavior

As robots become increasingly embedded in human–robot teamwork, understanding how humans perceive robot behavior is critical. This is especially relevant for swarm robots that rely on collective behavior to accomplish tasks. While prior research has explored how humans evaluate the abilities and behaviors of single robots, the perception of swarm robots remains relatively underexplored. Guided by the competence–warmth framework, we conducted a perception-based experiment in a collective search task, generating 125 robot teams by systematically manipulating three parameters: speed, separation distance, and local broadcast duration. Ninety participants observed the swarms, rated perceived warmth and competence, and reported team preferences. Results show that broadcast duration increased perceived warmth, separation distance enhanced perceived competence, and individual robot speed had no significant effect. Critically, social perceptions of warmth and competence were stronger predictors of team preference than task performance, with participants favoring swarms that appeared warm and competent over those that completed tasks fastest. These results underscore the importance of considering both technical performance and social attributes when designing robot swarms for effective collaboration with humans.