  Social robots, also known as service or assistant robots, have been developed
to improve the quality of human life in recent years. The design of socially
capable and intelligent robots can vary, depending on the target user groups.
In this work, we assess the effect of social robots' roles, functions, and
communication approaches in the context of a social agent providing service or
entertainment to users with developmental disabilities. In this paper, we
describe an exploratory study of interface design for a social robot that
assists people suffering from developmental disabilities. We developed series
of prototypes and tested one in a user study that included three residents with
various function levels. This entire study had been recorded for the following
qualitative data analysis. Results show that each design factor played a
different role in delivering information and in increasing engagement. We also
note that some of the fundamental design principles that would work for
ordinary users did not apply to our target user group. We conclude that social
robots could benefit our target users, and acknowledge that these robots were
not suitable for certain scenarios based on the feedback from our users.
