Artistic Pen Drawing on an Arbitrary Surface using an Impedance-controlled Robot

IEEE ICRA 2018

IEEE ICRA 2019

---

Abstracts

IEEE ICRA 2018, primary version without an RGB-D camera:

We present a semi-autonomous robotic pen-drawing system that is capable of creating pen art on an arbitrary surface with varying thickness of pen strokes but without reconstructing the surface explicitly. Our robotic system relies on an industrial, seven-degree-of-freedom (7DoF) manipulator that can be both position- and impedance-controlled. We use a vector-graphics engine to take an artist’s pen drawing as input and generate Bézier spline curves with varying offsets. In order to estimate geometric details of the target, unknown surface, during drawing, we rely on incremental and adaptive sampling on the surface using a combination of position and impedance control. Then, our control algorithm physically replicates this drawing on any arbitrary, continuous surface by impedance-controlling the manipulator. We demonstrate that our system can create visually-pleasing and complicated artistic pen drawings on general surfaces without explicit surface-reconstruction nor visual feedback.

IEEE ICRA 2019, extended version with distortion-free conformal mapping:

We present a robotic pen-drawing system that is capable of faithfully reproducing pen art on an unknown surface. Our robotic system relies on an industrial, seven degree-of-freedom(DoF) manipulator that can be both position- and impedance-controlled. In order to estimate a rough geometry of the target, continuous surface, we first generate a point cloud of the surface using an RGB-D camera, which is filtered to remove outliers and calibrated to the physical canvas surface. Then, our control algorithm physically reproduces digital drawing on the surface by impedance-controlling the manipulator. Our impedance-controlled drawing algorithm compensates for the uncertainty and incompleteness inherent to a point-cloud estimation of the drawing surface. Moreover, since drawing 2D vector pen art on a 3D surface requires surface parameterization that does not destroy the original 2D drawing, we rely on the least squares conformal mapping. Specifically, the conformal map reduces angle distortion during surface parameterization. As a result, our system can create distortion-free and complicated pen drawings on general surfaces with many unpredictable bumps robustly and faithfully.

---

Drawing Results

Pattern Drawing Results

Grid

Sierpiński curve

Snowflake

Artistic Drawing Results

Racoon

Kangaroo

Bear

Owl

Reproduced on Arbitrary Surfaces

Tiger1

Tiger2

Girl1

Girl2

---

Drawing Statistics

	Grid	Sierpiński curve	Snowflake	Racoon	Kangaroo	Bear	Owl	Tiger	Girl1	Girl2
# of Strokes	95	12	12	860	3,147	1,520	1,942	523	1,585	966
# of Control Points	6,930	2,360	4,128	69,350	80,580	66,910	159,895	72,845	59,205	35,600
Drawing Surface Size (mm)	384 x 216	432 x 216	384 x 192	252 x 491	252 x 491	252 x 491	252 x 491	126 x 262	126 x 262	94 x 184
Mapping Time (min.)	635	308	523	-	-	-	-	-	-	-
Execution Time (min.)	54	14	19	186	293	221	317	216	125	104

---

Bibtex

IEEE ICRA 2018, "Artistic Pen Drawing on an Arbitrary Surface using an Impedance-controlled Robot":

@inproceedings{song2018artistic,
    title={Artistic pen drawing on an arbitrary surface using an impedance-controlled robot},
    author={Song, Daeun and Lee, Taekhee and Kim, Young J},
    booktitle={2018 IEEE International Conference on Robotics and Automation (ICRA)},
    pages={4085--4090},
    year={2018},
    organization={IEEE}
}

IEEE ICRA 2019, "Distortion-free Robotic Surface-drawing using Conformal Mapping":

@inproceedings{song2019distortion,
    title={Distortion-free Robotic Surface-drawing using Conformal Mapping},
    author={Song, Daeun and Kim, Young J},
    booktitle={2019 International Conference on Robotics and Automation (ICRA)},
    pages={627--633},
    year={2019},
    organization={IEEE}
}

---

Contact

Ewha Computer Graphics Lab

Department of Computer Science & Engineering, Ewha Womans University
📍 52, Ewhayeodae-gil, Seodaemun-gu, Seoul, Korea, 03760
📞 +82-2-3277-6798

✉️ Daeun Song¹, daeunsong@ewhain.net
✉️ Young J. Kim¹, kimy@ewha.ac.kr
¹ Ewha Womans University, Korea