Gulletta, GianpaoloCosta e Silva, ElianaErlhagen, WolframMeulenbroek, RuudCosta, Maria Fernanda PiresBicho, Estela2021-11-242021-11-242021-03Gulletta, G., Silva, E. C. e, Erlhagen, W., Meulenbroek, R., Costa, M. F. P., & Bicho, E. (2021). A Human-like Upper-limb Motion Planner: Generating naturalistic movements for humanoid robots. International Journal of Advanced Robotic Systems. https://doi.org/10.1177/1729881421998585http://hdl.handle.net/10400.22/18936As robots are starting to become part of our daily lives, they must be able to cooperate in a natural and efficient manner with humans to be socially accepted. Human-like morphology and motion are often considered key features for intuitive human–robot interactions because they allow human peers to easily predict the final intention of a robotic movement. Here, we present a novel motion planning algorithm, the Human-like Upper-limb Motion Planner, for the upper limb of anthropomorphic robots, that generates collision-free trajectories with human-like characteristics. Mainly inspired from established theories of human motor control, the planning process takes into account a task-dependent hierarchy of spatial and postural constraints modelled as cost functions. For experimental validation, we generate arm-hand trajectories in a series of tasks including simple point-to-point reaching movements and sequential object-manipulation paradigms. Being a major contribution to the current literature, specific focus is on the kinematics of naturalistic arm movements during the avoidance of obstacles. To evaluate human-likeness, we observe kinematic regularities and adopt smoothness measures that are applied in human motor control studies to distinguish between well-coordinated and impaired movements. The results of this study show that the proposed algorithm is capable of planning arm-hand movements with human-like kinematic features at a computational cost that allows fluent and efficient human–robot interactions.engHumanoids and human-like roboticshuman-like motion planningcognitive systemshuman–robot interactionnaturalistic obstacles-avoidancejournal article10.1177/1729881421998585