This paper briefly discusses the benefits of applying Augmented Reality (AR) to facilitate intuitive robot programming,and presents a novel methodology for planning collision-free paths for an n degree-of-freedom (DOF) manipulator in an unknown environment.The targeted applications are where the end-effector is constrained to move along a visible 3D path/curve,which position is unknown,at a particular orientation with respect to the path,such as arc welding and laser cutting.The methodology is interactive as the human is involved in obtaining the 3D data points of the desired curve to be followed through performing a number of demonstrations,defining the free space relevant to the task,and planning the orientations of the end-effector along the curve.A Pieeewise Linear Parameterization (PLP) algorithm is used to parameterize the data points using an interactively generated piecewise linear approximation of the desired curve.A curve learning method based on Bayesian neural networks and reparameterization is used to learn and generate 3D parametric curves from the parametedzed data points.Finally,the orientation of the end-effector along the learnt curve is planned with the aid of AR.Two case studies are presented and discussed.