An optical fiber Bragg grating tactile sensor

Part of book or chapter of book English OPEN
Cowie, Barbara ; Allsop, Thomas D.P. ; Williams, John ; Webb, David ; Bennion, Ian ; Fisher, Matthew

Tactile sensors are needed for many emerging robotic and telepresence applications such as keyhole surgery and robot operation in unstructured environments. We have proposed and demonstrated a tactile sensor consisting of a fibre Bragg grating embedded in a polymer "finger". When the sensor is placed in contact with a surface and translated tangentially across it measurements on the changes in the reflectivity spectrum of the grating provide a measurement of the spatial distribution of forces perpendicular to the surface and thus, through the elasticity of the polymer material, to the surface roughness. Using a sensor fabricated from a Poly Siloxane polymer (Methyl Vinyl Silicone rubber) spherical cap 50 mm in diameter, 6 mm deep with an embedded 10 mm long Bragg grating we have characterised the first and second moment of the grating spectral response when scanned across triangular and semicircular periodic structures both with a modulation depth of 1 mm and a period of 2 mm. The results clearly distinguish the periodicity of the surface structure and the differences between the two different surface profiles. For the triangular structure a central wavelength modulation of 4 pm is observed and includes a fourth harmonic component, the spectral width is modulated by 25 pm. Although crude in comparison to human senses these results clearly shown the potential of such a sensor for tactile imaging and we expect that with further development in optimising both the grating and polymer "finger" properties a much increased sensitivity and spatial resolution is achievable.
  • References (10)

    1. D. I. Hanson and B. D. Prowell, “Evaluation of circular texture meter for measuring surface texture of pavements,” tech. rep., National Center for Asphalt Technology, Auburn University, Auburn, Alabama, September 2004. NCAT Report 04-05.

    2. “Strategic plan for improved concrete pavement surface characteristics.” http://www.cptechcenter.org/publications/ surface char exec summary.pdf, July 2006.

    3. P. Tomassini, L. Rovati, G. Sansoni, and F. Docchio, “Novel optical sensor for the measurement of surface texture,” Review of Scientific Instruments 72, pp. 2207-2213, April 2001.

    4. B. V. Jayawant, “Tactile sensing in robotics,” Journal of Physics. E: Scientific. Instruments 22(9), pp. 684-692, 1989.

    5. J. Dargahi and S. Payandeh, “Surface texture measurement by combining signals from two sensing elements of a piezoelectric tactile sensor.,” in Proceedings of the SPIE, 3376, pp. 122-128, The International Society for Optical Engineering, 1998.

    6. Y. Tada, K. Hosoda, Y. Yamasaki, and M. Asada, “Sensing the texture of surfaces by anthropomorphic soft fingertips with multi-modal sensors,” in Proceedings 2003 IEEE/RSJ International Conference on Intelligent Robots and System, 1, pp. 27-31, (Las Vegas, USA), October 2003.

    7. H. Shinoda, M. Uehara, and S. Ando, “A tactile sensor using three-dimensional structure,” in Proceedings, 1993 IEEE International Conference on Robotics and Automation, 1, pp. 435-441, IEEE, May 1993.

    8. Y. Mukaibo, H. Shirado, M. Konyo, and T. Maeno, “Development of a texture sensor emulating the tissue structure and perceptual mechanism of human fingers,” in Proceedings of the 2005 IEEE International Conference on Robotics and Automation, pp. 2576-8251, IEEE, (Barcelona, Spain), April 2005.

    9. D. K. Pai and P. R. Rizun, “The what: A wireless haptic texture sensor,” in Proc. Eleventh Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems, 2003.

    10. X. Zhang, Z. Wu, and B. Zhang, “Strain dependence of fiber bragg grating sensors at low temperature,” Optical Engineering 45, may 2006.

  • Metrics
    No metrics available
Share - Bookmark