Soft tissues of human body have complex structures and different mechanical behaviors than those of traditional engineering materials. There is a great urge to understand tissue behavior of human body. Experimental data is needed for improvement of soft tissue modeling and advancement in implants and prosthesis, as well as diagnosis of diseases. Mechanical behavior and responses change when tissue loses its liveliness and viability. One of the techniques for soft tissue testing is indentation, which is applied on live tissue in its physiological environment. Indentation affords several advantages over other types of tests such as uniaxial tension, biaxial tension, and simple shear and suction, thus it is of interest to develop new indentation techniques from which more valid data can be extracted. In this study a new indenter device was designed and constructed. Displacement and force rate cyclic loading, and relaxation experiments were conducted on human arm. The in-vivo force rate controlled cyclic loading test method which is novel is compared with the traditional displacement controlled cyclic loading tests. Anisotropic behavior of tissue cannot be determined by axisymmetric tips, therefore ellipsoid tips were used for examining anisotropy and inplane material direction of bulk soft tissues
Soft tissues of human body have complex structures and differentmechanical behaviors than those of traditional engineering materials. There is agreat urge to understand tissue behavior of human body. Experimental data isneeded for improvement of soft tissue modeling and advancement in implants andprosthesis, as well as diagnosis of diseases. Mechanical behavior and responseschange when tissue loses its liveliness and viability. One of the techniques for softtissue testing is indentation, which is applied on live tissue in its physiologicalenvironment. Indentation affords several advantages over other types of tests suchas uniaxial tension, biaxial tension, and simple shear and suction, thus it is ofinterest to develop new indentation techniques from which more valid data can beextracted. In this study a new indenter device was designed and constructed.Displacement and force rate cyclic loading, and relaxation experiments wereconducted on human arm. The in-vivo force rate controlled cyclic loading testmethod which is novel is compared with the traditional displacement controlledcyclic loading tests. Anisotropic behavior of tissue cannot be determined by axisymmetrictips, therefore ellipsoid tips were used for examining anisotropy and inplanematerial direction of bulk soft tissues.