  This paper presents a planning algorithm designed to improve cooperative
robot behavior concerning human comfort during forceful human-robot physical
interaction. Particularly, we are interested in planning for object grasping
and positioning ensuring not only stability against the exerted human force but
also empowering the robot with capabilities to address and improve human
experience and comfort. Herein, comfort is addressed as both the muscular
activation level required to exert the cooperative task, and the human spatial
perception during the interaction, namely, the peripersonal space. By
maximizing both comfort criteria, the robotic system can plan for the task
(ensuring grasp stability) and for the human (improving human comfort). We
believe this to be a key element to achieve intuitive and fluid human-robot
interaction in real applications. Real HRI drilling and cutting experiments
illustrated the efficiency of the proposed planner in improving overall comfort
and HRI experience without compromising grasp stability.
