The Performance of a Deformable-Membrane Tactile Sensor: Basic Results on Geometrically-Defined Tasks

Abstract

The limitations of rigid fingertips in the precise and algorithmic study of manipulation have been discussed in many works, some dating back more than a decade. Despite that fact, much of the work in dexterous manipulation has continued to use the "point-contact" model for finger-object interactions. In fact, most of the existing tactile sensing technologies are not adaptable to deformable fingertips. The authors present the results of tactile sensing experiments with a new, deformable, gel-filled tactile sensor. Previous work (Shimoga & Goldenberg) has shown the superiority of gel fingertips for force dissipation and conformability. This sensor reconstructs the shape of an elastic membrane using image data, thus providing a rich set of tactile information. The experiments presented here demonstrated the performance of this sensor in simple tasks involving contact localization, spatial resolution, contact depth, and curvature discrimination. For small deformations of the membrane, the contact localization error was less than 0:1mm over a 4 sq cm area, while the spatial resolution was better than 2mm. The sensor can accurately determine deformation depth for small deformations. Curvature estimation is monotonic, however the estimates suffer from the low resolution of the numerical data used to compute derivatives.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1999
Accession Number
ADA439988

Entities

People

  • Dimitris Hristu
  • Nicola J. Ferrier
  • Roger W. Brockett

Organizations

  • University of Maryland

Tags

Communities of Interest

  • Autonomy
  • Energy and Power Technologies
  • Sensors

DTIC Thesaurus Topics

  • Accuracy
  • Algorithms
  • Curvature
  • Detectors
  • Diameters
  • Displacement
  • Errors
  • Flow Fields
  • Geometric Forms
  • Grids
  • Image Processing
  • Lines (Geometry)
  • Measurement
  • Membranes
  • Pressure Distribution
  • Three Dimensional
  • Universities

Readers

  • Computer Vision.
  • Robotics and Automation.
  • Structural Dynamics.