  The interaction of Older adults with robots requires effective feedback to
keep them aware of the state of the interaction for optimum interaction
quality. This study examines the effect of different feedback modalities in a
table setting robot assistant for elder care. Two different feedback modalities
(visual and auditory) and their combination were evaluated for three complexity
levels. The visual feedback included the use of LEDs and a GUI screen. The
auditory feedback included alerts (beeps) and verbal commands. The results
revealed that the quality of interaction was influenced mainly by the feedback
modality, and complexity had less influence. The verbal feedback was
significantly preferable and increased the involvement of the participants
during the experiment. The combination of LED lights and verbal commands
increased participants' understanding contributing to the quality of
interaction.
