  An important factor in developing control models for human-robot
collaboration is how acceptable they are to their human partners. One such
method for creating acceptable control models is to attempt to mimic human-like
behaviour in robots so that their actions appear more intuitive to humans. To
investigate how task complexity affects human perception and acceptance of
their robot partner, we propose a novel human-based robot control model for
obstacle avoidance that can account for the leader-follower dynamics that
normally occur in human collaboration. The performance and acceptance of the
proposed control method were evaluated using an obstacle avoidance scenario in
which we compared task performance between individual tasks and collaborative
tasks with different leader-follower dynamics roles for the robotic partner.
The evaluation results showed that the robot control method is able to
replicate human behaviour to improve the overall task performance of the
subject in collaboration. However, regarding the acceptance of the robotic
partner, the participants' opinions were mixed. Compared to the results of a
study with a similar control method developed for a less complex task, the new
results show a lower acceptance of the proposed control model, even though the
control method was adapted to the more complex task from a dynamic standpoint.
This suggests that the complexity of the collaborative task at hand increases
the need not only for a more complex control model but also a more socially
competent control model.
