This article presents the implementation and experimental validation of a control system dedicated to human robot physical interaction during object handovers. Our control law defines the trajectory of the robotic arm towards a previously unknown handover location based on the Dynamic Movement Primitives formalism adapted for human robot object handover. The control law was deployed on a Kuka Light-Weight Arm equipped with the Azzurra anthropomorphic hand. We employed an industrial-like setting involving three different human postures for object handover in order to evaluate the performance and user experience of our control law and its generalizability. The evaluation was conducted over 1000 object handover trials between the human and robot partners, and the kinematic data and subjective experience were gathered for each trial. The outcomes of this evaluation validate the current implementation and guide the next steps towards more efficient and fluid human robot interaction.

This article presents the design and execution of the experiments used to develop and evaluate a robot prototype system for fluent Human-Robot object handover interactions. A key aspect of our experimental methodology is the deep integration between Human-Robot and Human-Human object handover experiments. This provides a solid baseline and knowledge base for the prototype evaluation, both in terms of movement dynamics and in subjective user evaluation.

This article presents the current state of an ongoing work on Human-Robot interaction in which two partners collaborate during an object hand-over interaction. The manipulator control is based on the Dynamic Movement Primitives model, specialized for the object hand-over context. The proposed modifications enable finer control of the dynamic of the DMP to align it to human control strategies, where the contributions of the feedforward and feedback parts of the control are different to the original DMP formulation. Furthermore, the proposed scheme handles moving goals. With these two modifications, the model no longer requires an explicit estimation of the exchange position and it can generate motion purely reactively to the instantaneous position of the human hand. The quality of the control system is evaluated through an extensive comparison with ground truth data related to the object interaction between two humans acquired in the context of the European project CogLaboration which envisages an application in an industrial setting.

This paper extends the previous results on position tracking for bilateral teleoperators with constant time-delays, reported in Nuno et al. IEEE Trans. Robot., vol. 24, no. 3, pp. 753-758, June 2008, to the case of variable time-delays in the teleoperator's communications. The key part is the extension of a previous Lemma that is used to prove that P+d or PD+d controllers can stabilize the teleoperator under variable timedelays, and moreover, they provide position tracking. The paper outlines the conditions under which velocities and position errors, of the nonlinear teleoperator, are bounded, and using Barbalat's Lemma, it is proved asymptotic converge to zero if the local manipulator stands still and the remote manipulator does not interact with the environment. Simulations and real experiments validate the proposed schemes. The experiments have been performed using the Internet as communication channel between Urbana-Champaign, USA and Barcelona, Spain.