TY - INPR U1 - Preprint A1 - Quiroga, Natalia A1 - Mitrevski, Alex A1 - Plöger, Paul G. T1 - Learning Human Body Motions from Skeleton-Based Observations for Robot-Assisted Therapy N2 - Robots applied in therapeutic scenarios, for instance in the therapy of individuals with Autism Spectrum Disorder, are sometimes used for imitation learning activities in which a person needs to repeat motions by the robot. To simplify the task of incorporating new types of motions that a robot can perform, it is desirable that the robot has the ability to learn motions by observing demonstrations from a human, such as a therapist. In this paper, we investigate an approach for acquiring motions from skeleton observations of a human, which are collected by a robot-centric RGB-D camera. Given a sequence of observations of various joints, the joint positions are mapped to match the configuration of a robot before being executed by a PID position controller. We evaluate the method, in particular the reproduction error, by performing a study with QTrobot in which the robot acquired different upper-body dance moves from multiple participants. The results indicate the method's overall feasibility, but also indicate that the reproduction quality is affected by noise in the skeleton observations. Y1 - 2022 AX - 2207.12224 SP - 6 S1 - 6 PB - arXiv ER -