PCTac: Mechanochromic Photonic-Crystal Tactile Sensor for Dexterous Manipulation
PCTac: Mechanochromic Photonic-Crystal Tactile Sensor for Dexterous Manipulation
This paper introduces PCTac, an open-source mechanochromic photonic-crystal fingertip sensor that converts local stress into a spatially resolved structural-color field. The authors demonstrate a repeatable relationship between applied normal load and observed hue response, integrating this representation directly into a Diffusion Policy. Evaluated across 90 physical rollouts on three real-robot manipulation tasks, PCTac Hue achieves 68 successes (75.6%), outperforming PCTac RGB (60 successes), Wedge RGB (57 successes), and vision-only approaches (29 successes). The sensor shows particular promise in perturbed test-tube insertion, achieving 16/30 successes compared to 13/30 for tactile RGB baselines and 1/30 for vision-only.
Source: arXiv Robotics — research abstracts · Read original article ↗
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Publisher-reported claims, with original evidence. These results have not been independently verified by RoboSignal.
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physical rollouts
90
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pen-source mechanochromic PC fingertip that uses a dense hue field as its tactile observation. Loading characterization demonstrates a repeatable relationship between the applied normal load and the observed hue response. We further integrate this representation directly into a Diffusion Policy and evaluate it on three real-robot manipulation tasks. Across 90 physical rollouts, PCTac Hue achieves 68 successes (75.6\%
Open source S4
- paper: not_reported
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- weights: not_reported
- dataset: not_reported
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pen-source mechanochromic PC fingertip that uses a dense hue field as its tactile observation. Loading characterization demonstrates a repeatable relationship between the applied normal load and the observed hue response. We further integrate this representation directly into a Diffusion Policy and evaluate it on three real-robot manipulation tasks. Across 90 physical rollouts, PCTac Hue achieves 68 successes (75.6\%
Open source S4
), compared with 60 (66.7\%) for PCTac RGB, 57 (63.3\%) for Wedge RGB, and 29 (32.2\%) for vision-only. PCTac Hue also achieves the highest observed success rate on each evaluated task, including Perturbed Test-Tube Insertion, where it achieves 16/30 successes versus 13/30 for tactile RGB baselines and 1/30 for vision-only. These results demonstrate the potential of mechanochromic structural color as a compact, load-
Open source S5
sensitive tactile representation for robot learning and closed-loop manipulation. Project page: https://bey0ndt1me.github.io/PCTac-page/.
Open source S6
Source：arXiv Robotics — research abstracts · arxiv.org