Transparent Robot Behavior Using Augmented Reality in Close HumanRobot Interaction Most robots consistently repeat their motion with out changes in a precise and consistent manner. But nowadays there are also robots able to dynamically change their motion and plan according to the people and environment that surround them. Furthermore, they are able to interact with humans and cooperate with them. With no information about the robot targets and intentions, the user feels uncomfortable even with a safe robot. In close humanrobot collaboration, it is very important to make the user able to understand the robot intentions in a quick and intuitive way. In this work we have developed a system to use augmented reality to project directly into the workspace useful information. The robot intuitively shows its planned motion and task state. The AR module interacts with a vision system in order to display the changes in the workspace in a dynamic way. The representation of information about possible collisions and changes of plan allows the human to have a more comfortable and efficient interaction with the robot. The system is evaluated in different setups.

An Augmented Reality Interface for HumanRobot Interaction in Unconstrained Environments As robots start to become ubiquitous in the personal workspace, it is necessary to have simple and intuitive interfaces to interact with them. In this paper, we propose an augmented reality (AR) interface for humanrobot interaction (HRI) in a shared working environment. By fusing markerbased and markerless AR technologies, a mobile AR interface is created that enables a smartphone to detect planar surfaces and localize a manipulator robot in its working environment while obviating the need for a controlled or constrained environment. The AR interface and robot manipulator are integrated to render a system that enables users to perform pickandplace task effortlessly. Specifically, a smartphonebased AR application is developed that allows a user to select any location within the robotu0027s workspace by merely touching on the smartphone screen. Virtual objects, rendered at userselected locations, are used to determine the pick and place locations of objects in the real world. The virtual objectu0027s start and end points, originally specified in the smartphone camera coordinate frame, are transformed into the robot coordinate frame for the robot manipulator to autonomously perform the assigned task. A user study is conducted with participants to evaluate the system performance and user experience. The results show that the proposed AR interface is userfriendly and intuitive to operate the robot, and it allows users to communicate their intentions through the virtual object easily.