Constraint Path Planning for an Autonomous Wall Spray Coating Robot The wall spray coating task requires robot to handle a sprayhead to cover the whole interior wall surface. In this paper a manipulator is used to complete such task where a Cartesian constraint path is firstly generated by breadth first search (BFS) based on the boustrophedon decomposition, and then the Cartesian path will be converted to joint sequences. In addition, corners formed by two walls as the nondifferentiable area are analyzed and fitted by Bezier curve. Finally, a sphere cap constraint planner is proposed to deal with wall suspended with multiple aligned pipelines. A 6DOF KUKA robot arm was employed to do the spray coating task in a building, and the experiments will demonstrate the effectiveness and efficiency of the proposed approach.

3D Printing And Freeform Surface Coating Based on 6DOF Robot At present, most of the 3D printing facilities are 3 degrees of freedom (DOF) that formed by planar stacking, which cannot achieve freeform surface spraying or other high DOF required operations. However, in a way, this problem can be solved by using a 6axis manipulator, which is the future development trend of the 3D printing facilities. In this paper, a UR manipulator is used to realize the 3D printing function, especially the coating procedure of biomaterials, such as coating hydroxyapatite on the surface of artificial models. By dismantling the steps of our methodology, we firstly obtain the point cloud data of the 3D models and reconstruct the point cloud with a straightforward algorithm for the further subsequent path planning of UR manipulator for 3D printing. After that, the control parameter calculation of the printing path of UR is explained in detail. Finally, the printing accuracy of UR and interlayer uniformity of the 3D model are optimized by iterating the related experiments. The highquality printed samples of the 3D models prove that our research has successfully achieved the practical application of UR manipulator in 3D printing.