Effect of Twisted-Yarn Architecture on Pressure and Proximity Sensing Characteristics of Textile Capacitive Sensors for Robotic Skin

Effect of Twisted-Yarn Architecture on Pressure and Proximity Sensing Characteristics of Textile Capacitive Sensors for Robotic Skin

|Authors: Ishtia Zahir, Eslam Saleh, Maryam Rezayati, Güunter Grabher, Gaffar Hossain

|Venue: arXiv preprint | Year: 2026

|arXiv: 2608.14406v1

Abstract

Textile-integrated capacitive sensors offer flexible and conformable tactile sensing for wearable electronics and human-robot interaction; however, the influence of yarn-level architecture on capacitive transduction characteristics remains insufficiently quantified. This work presents a textile capacitive sensing platform based on silver-coated yarns coated with polydimethylsiloxane and assembled into one-, two-, and four-layer twisted configurations. The influence of effective electrode overlap area and inter-fiber separation on the capacitive response is systematically investigated, enabling architecture-dependent tuning of pressure and proximity sensing characteristics. Pressure was calculated using the localized single-fiber contact area, corresponding to stresses of 0.4-3.9 MPa. Increasing the layer number improved mechanical strength and sensing performance: elongation at break increased from 37.5% to 62.5% and 85.0%, while the maximum load increased from 23.3 to 42.7 and 89.7 N. Sensitivity increased with layer number and frequency, reaching 0.1331 MPa$^{-1}$ for the four-layer sensor at 100 kHz. The four-layer configuration also exhibited low hysteresis, minimal thermal drift from 25 to 90 $^\circ$C, and stable operation over 15,000 cycles. Proximity detection ranges of 60, 50, and 40 mm were obtained for the one-, two-, and four-layer sensors, respectively, revealing an architecture-dependent sensitivity-range trade-off. A 4$\times$4 textile sensing array enabled spatial contact mapping, while robotic-arm integration demonstrated real-time touch and proximity detection with an end-to-end robotic system latency (from detection to robot reaction) of 403 ms. The results establish yarn architecture as a tunable design parameter governing the measurement characteristics of textile-integrated capacitive sensing systems.

Key Contributions

• Textile-integrated capacitive sensors offer flexible and conformable tactile sensing for wearable…
• This work presents a textile capacitive sensing platform based on silver-coated yarns coated with…
• The influence of effective electrode overlap area and inter-fiber separation on the capacitive re…
• Pressure was calculated using the localized single-fiber contact area, corresponding to stresses …
• Increasing the layer number improved mechanical strength and sensing performance: elongation at b…

Topics

• vision
• reinforcement-learning
• human-robot-interaction
• tactile

Code & Data

No code repository linked in paper metadata.

BibTeX

@article{Zahir2026_260814406v1,
  title     = {Effect of Twisted-Yarn Architecture on Pressure and Proximity Sensing Characteristics of Textile Capacitive Sensors for Robotic Skin},
  author    = {Ishtia Zahir and Eslam Saleh and Maryam Rezayati and Güunter Grabher and Gaffar Hossain},
  year      = {2026},
  eprint    = {2608.14406v1},
  archivePrefix = {arXiv},
  primaryClass  = {cs.RO},
  url       = {https://arxiv.org/abs/2608.14406v1}
}