  Service robots for the domestic environment are intended to autonomously
provide support for their users. However, state-of-the-art robots still often
get stuck in failure situations leading to breakdowns in the interaction flow
from which the robot cannot recover alone. We performed a multi-user
Wizard-of-Oz experiment in which we manipulated the robot's behavior in such a
way that it appeared unexpected and malfunctioning, and asked participants to
help the robot in order to restore the interaction flow. We examined how
participants reacted to the robot's error, its subsequent request for help and
how it changed their perception of the robot with respect to perceived
intelligence, likability, and task contribution. As interaction scenario we
used a game of building Lego models performed by user dyads. In total 38
participants interacted with the robot and helped in malfunctioning situations.
We report two major findings: (1) in user dyads, the user who gave the last
command followed by the user who is closer is more likely to help (2)
malfunctions that can be actively fixed by the user seem not to negatively
impact perceived intelligence and likability ratings. This work offers insights
in how far user support can be a strategy for domestic service robots to
recover from repeating malfunctions.
