When robots meet art, it will trigger unprecedented sparks between artists and engineers. The robot drawing workshop introduced a process to convert camera images to robot-drawn graphics. The initial image was captured by a webcam, then processed by parametrical tools to generate the tool path for the robot. The robot draws grid lines on paper, and the stroke weight varies depending on the lightness value of the pixels. This process has thus created a physical presentation of virtual parameters. This method can also be found in other digital fabrication cases, indicating we should always understand the operation of hardware to be able to integrate it with the software.