Shear deformation induced by shear stress is one of the major forms of interaction between the locomotion mechanism and the intestines. Relatively few experimental studies using locomotion mechanisms have been perform...Shear deformation induced by shear stress is one of the major forms of interaction between the locomotion mechanism and the intestines. Relatively few experimental studies using locomotion mechanisms have been performed to investigate the viscoelastic property of intestines. There is a lack of reliable data regarding the relative movement between various locomotion mechanisms and the small intestine, and how that movement affects the measurement of shear displacement. In this work, a novel platform was constructed with two elaborately designed clamps that could securely fix both sides of an intestine sample using negative gas adsorption. The platform was also integrated with noncontact measuring equipment to record the thickness of the intestine sample. Subsequently, preservation measure was applied to porcine intestine, and multiple intestine samples were prepared and tested under strains of 20%, 50%, 80% and 100%. A five-element viscoelastic model that was fitted to multiple sets of data could accurately predict the biomechanical property of the intestines. Finally, a new criterion, the loss factor, was calculated with the parameters of the five-element model to represent the dynamic behavior of soft tissue, and it was used to verify the reliability and effectiveness of the experimental setup and results.展开更多
基金supported by the National Key R&D Program of China(Grant No.2018YFC0115101)the National Natural Science Foundation of China(Grant No.61503370)Open Fund of State Key Laboratory of Robotics of China(Grant No.2017-O10)
文摘Shear deformation induced by shear stress is one of the major forms of interaction between the locomotion mechanism and the intestines. Relatively few experimental studies using locomotion mechanisms have been performed to investigate the viscoelastic property of intestines. There is a lack of reliable data regarding the relative movement between various locomotion mechanisms and the small intestine, and how that movement affects the measurement of shear displacement. In this work, a novel platform was constructed with two elaborately designed clamps that could securely fix both sides of an intestine sample using negative gas adsorption. The platform was also integrated with noncontact measuring equipment to record the thickness of the intestine sample. Subsequently, preservation measure was applied to porcine intestine, and multiple intestine samples were prepared and tested under strains of 20%, 50%, 80% and 100%. A five-element viscoelastic model that was fitted to multiple sets of data could accurately predict the biomechanical property of the intestines. Finally, a new criterion, the loss factor, was calculated with the parameters of the five-element model to represent the dynamic behavior of soft tissue, and it was used to verify the reliability and effectiveness of the experimental setup and results.