Softness measurements for open-cell foam materials and human soft tissue

  title={Softness measurements for open-cell foam materials and human soft tissue},
  author={Winnie Yu and Yongbao Li and Yong Ping Zheng and N.-Y. Lim and M. H. Lu and Jintu Fan},
  journal={Measurement Science and Technology},
In this paper, methods of measuring the softness of open-cell polyurethane foams in terms of their Young's modulus using indentation methods are investigated and shown to be in agreement with values determined by normal compression tests. The comparison involved the use of a formula relating Young's modulus for elastomers to the axial indentation forces on a cylindrical probe. This had been developed for cartilage and verified for other biological tissues and could not automatically be assumed… Expand
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An ultrasound indentation system for biomechanical assessment of soft tissues in vivo was developed and the specific application is for stump tissue assessment in the design of prosthetics. Expand
A Soft Mannequin for the Evaluation of Pressure Garments on Human Body
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An efficient numerical algorithm is developed to compute all three material coefficients of cartilage in situ on the joint surface from the indentation creep experiment, and the average values of the aggregate modulus are determined. Expand
Estimating the effective Young's modulus of soft tissues from indentation tests--nonlinear finite element analysis of effects of friction and large deformation.
It is found that the factor kappa increases almost proportionally to the increase of the indentation depth, especially obvious with a larger Poisson's ratio v and a larger aspect ratio a/h. Expand
Durometer Hardness and the Stress-Strain Behavior of Elastomeric Materials
Abstract The Durometer hardness test is one of the most commonly used measurements to qualitatively assess and compare the mechanical behavior of elastomeric and elastomeric-like materials. ThisExpand
Indentor tests and finite element modeling of bulk muscular tissue in vivo.
The quasi-static response of bulk muscular tissue to indentation was measured on the posterior lower legs of living human subjects, and the composite material stiffness of the tissue was modeled using a materially and geometrically nonlinear, large-strain finite element formulation. Expand
A mathematical analysis for indentation tests of articular cartilage.
Solutions for the indentation of the layer by the plane end of a rigid circular cylinder and by a rigid sphere are suggested as useful for the determination of the elastic shear modulus of intact cartilage. Expand
An Analysis of the “Durometer” Indentation
Abstract The mechanics of the indentation of elastomers by the “Durometer” (Shore A) hardness tester is analysed using the theory of elasticity to derive an interrelation between the Shore hardnessExpand
Accuracy and reliability testing of a portable soft tissue indentor
Data from this portable indentor device are reliable, accurate, and sensitive enough to identify mechanical properties of human tissues. Expand
A new method for theoretical analysis of static indentation test.
A new mathematical method was developed to study the indentation problem of an infinite elastic layer overlaid on a rigid foundation and obtained closed-form solutions through an infinite series. Expand