One of the challenges facing the field of social robotics re-
search is to achieve useful robots that users trust and regularly employ
in their daily lives. That is, robots with a high degree of engagement
with their users. To date, few social bots have achieved massive sales
success coupled with a satisfactory and continuous user experience over
time by the users who interact with them. This may be partly due to
the lack of maturity of certain technologies involved in developing these
social robots, but undoubtedly a key factor —and one that is being taken
into account very little— is the psychological factor when designing and
developing these technological devices. There are several psychological
techniques that, when correctly applied and combined, can significantly
increase the engagement in the interaction between humans and robots.
In this paper, we will unravel what these techniques are and how we can
apply them in this field of research.