Automatic and Flexible Robotic Drawing on Complex Surfaces With an Industrial Robot

In industrial applications, planning and executing robot motions are crucial steps for manufacturing processes. Following the trend for customization, more flexible production systems are needed to quickly adapt the planned robot motion to new user inputs. In this work, a user-defined 2-D input pattern has to be drawn by a robot on a given 3-D object in an automated workflow. For this, two projection methods to map the 2-D input pattern to the 3-D object are presented, and robot trajectories are automatically generated based on the result of the projection methods. Furthermore, two control concepts, i.e., a pure motion control and a hybrid force/motion control, are investigated and validated by experimental results. In addition, a precise force estimation is performed to guarantee a constant normal contact force during the drawing process. The proposed automated workflow is applicable to various industrial processes, e.g., spray painting, cutting, and engraving, and provides an easy way to plan and execute robot motions based on user inputs.