This technology is a path generation method and computing device for a robot consisting of a manipulator mounted on a mobile base, designed to draw 2D images onto large, curved 3D surfaces by generating both a set of drawing poses and the robot's movement path. It maps drawing points by unfolding the 3D surface into a 2D parametric domain and determines the movement path based on coverage circles, which represent the manipulator's workspace, and corresponding bounding circles for the base's position.
Existing robotic drawing systems are designed for flat canvases, leading to image distortion when drawing on non-planar surfaces. Furthermore, due to the limited reach of the manipulator arm, it is difficult to plan how far and where the robot should move when handling large surfaces such as walls or vehicle bodies.
This technology compensates for missing points not mapped in the 2D parametric domain by applying bilinear interpolation to the quadrilateral formed by the four surrounding matching points, then inverse-transforms them to the 3D surface to obtain drawing poses. Coverage circles are determined by selecting candidate circles that cover the most points on the profile curve projected onto the x-y plane. The bounding circle center and base pose are placed perpendicular to the line connecting the two poles of each circle, with the path defined by connecting these centers. Applicable to building murals, ship/aircraft marking, and large-scale painting, it enables continuous, distortion-free drawing on expansive curved surfaces with minimal base stops.
This invention was developed with support from the Ministry of Science and ICT's XRbot-Pro: Extended Reality-based Robotic Virtual Production project.
US12569997B2
