  Service robots are increasingly employed in the hospitality industry for
delivering food orders in restaurants. However, in current practice the robot
often arrives at a fixed location for each table when delivering orders to
different patrons in the same dining group, thus requiring a human staff member
or the customers themselves to identify and retrieve each order. This study
investigates how to improve the robot's service behaviours to facilitate clear
intention communication to a group of users, thus achieving accurate delivery
and positive user experiences. Specifically, we conduct user studies (N=30)
with a Temi service robot as a representative delivery robot currently adopted
in restaurants. We investigated two factors in the robot's intent
communication, namely visualisation and movement trajectories, and their
influence on the objective and subjective interaction outcomes. A robot
personalising its movement trajectory and stopping location in addition to
displaying a visualisation of the order yields more accurate intent
communication and successful order delivery, as well as more positive user
perception towards the robot and its service. Our results also showed that
individuals in a group have different interaction experiences.
