Accession Number : ADA187464

Title :   Tactile Sensing and Inverse Problems,

Corporate Author : MARYLAND UNIV COLLEGE PARK

Personal Author(s) : Yang, R ; Krishnaprasad, P S

PDF Url : ADA187464

Report Date : Oct 1987

Pagination or Media Count : 32

Abstract : In recognizing a grasped object or grasp an object stably with a multifingered robotic hand, tactile sensors mounted on robot fingers have been identified as essential detecting tool. In general, grasp stability has two requirements: sliding avoidance and excess force avoidance. Hence, it is required that a tactile sensor be able to detect the nature of the force distribution which exists between the surface of the grasped object and the robot finger. Several kinds of tactile sensors have been designed based on electro-optics, piezoresistive, or piezoelectric properties, etc.. Typically, these sensors are not used to measure the contact force directly, but to measure the interior strain or stress in an elastic finger pad. When sharp and rigid objects, e.g., a wedge indentor, indent an elastic material, very high stress is developed at the contact surface. This stress is reduced by distance from the contact area, so a fragile sensor would be better protected with a layer soft material. Another advantage of using an elastic covering is that the contact area becomes large so that grasp stability may be enhanced and the features of grasped objects better distinguished. The goal of this paper is to study how a surface force profile may be estimated from the information on strain or stress distribution detected by tactile sensors. This problem is referred to as the inverse problem since we can consider the stress or strain within an elastic material as the response due to surface loading.

Descriptors :   *DETECTORS, *FINGERS, *MECHANICAL COMPONENTS, *ROBOTS, *TOUCH, AVOIDANCE, DETECTION, DISTRIBUTION, ELASTIC PROPERTIES, ELECTROOPTICS, INVERSION, LAYERS, MATERIALS, PIEZOELECTRIC EFFECT, RANGE(DISTANCE), REQUIREMENTS, RIGIDITY, SURFACES, SHARPNESS, STRESSES, SLIDING, LOADS(FORCES), DISCRETE FOURIER TRANSFORMS, PROBLEM SOLVING

Subject Categories : Cybernetics
      Operations Research

Distribution Statement : APPROVED FOR PUBLIC RELEASE