Replicating Painting Strokes: Shape Aware Dynamic Motion Primitives for Robotic Manipulation
Jelena Vuleti ́c, Pero Drobac, Bruno Mari ́c and Matko Orsag
AI summary
Problem
Replicating delicate tasks like painting requires simultaneous control of motion and tool deformation, which is difficult with simple deformable tools and existing sensing methods.
Approach
The authors combine shape-aware Dynamic Motion Primitives with a custom magnetic gradiometer to estimate tool curvature at 1 kHz, feeding this into a linear PD/P controller that maintains shape while tracking demonstrated trajectories.
Key results
- Shape-aware DMPs enable simultaneous motion planning and real-time curvature servoing at 1 kHz
- Custom magnetic gradiometer accurately estimates scraper bending angle without external calibration
- Synthesized linear control algorithm maintains tool shape while replicating human-demonstrated trajectories
- System successfully reproduces complex paintings under altered experimental conditions
Why it matters
Provides a cost-effective, high-speed solution for soft robotic manipulation in delicate industrial and artistic tasks requiring precise tool deformation control.
Abstract
This work proposes derivation and experimental validation of the robotic manipulation framework based on the shape aware Dynamic Motion Primitives (DMPs) that enables precise shape servoing relying on magnetic based sensing. The magnetic sensing system, with the sensor sampling rate of 1 kHz, outputs measurements that can be used as an estimate of the bending angle of the deformable plastering scraper, approx- imated as a constant curvature segment. Synthesized linear control algorithm encompasses PD controller that accounts for deviations in the scraper bending angle and P controller that enables maintaining end effector pitch angle reference. The proposed control system is combined with the Programming by Demonstration (PbD) approach. Consequently, the presented robotic painting system can follow the demonstrated scraper bending angle and end effector pitch angle reference values while replicating the demonstrated trajectory, even in signifi- cantly altered experimental conditions.