title: On the derivation of passive 3D material parameters from 1D stress-strain data of hydrostats.
abstract: The present paper offers a novel equivalent-pressure approach to the derivation of isotropic passive muscle parameters from 1D stress-strain data sets. The approach aims specifically at the identification of material parameters in hydrostats, in which case the equivalent-force approach that is common for skeletal muscle generates suboptimal results. Instead, an equivalent-pressure hypothesis is formulated which provides more adequate boundary conditions for the concluding curve-fitting procedure. The choice of an appropriate constitutive description is decisive for the quality of the deduced parameter sets. Here, a Yeoh material law is chosen for the model of a squid tentacle. Parameters derived by both, equivalent-force and equivalent-pressure algorithms, are compared, illustrating the applicability limits of either. They are implemented in a finite element model of the tentacle. A prey-capture strike is simulated and compared to data from literature. The hydrostat-specific interpretation of the equivalent-pressure hypothesis is shown to match the reference very well.
authors.affiliation: Institute of Structural Mechanics, Bauhaus Universität Weimar, Germany. benjamin.winkel@uni-weimar.de
authors.forename: Benjamin
authors.initials: B
authors.lastname: Winkel
authors.forename: Axel
authors.initials: A
authors.lastname: Schleichardt
mesh_terms: D000465:Algorithms; D000818:Animals; D001696:Biomechanical Phenomena / Q000502:physiology; D003198:Computer Simulation; D049832:Decapodiformes; D020342:Finite Element Analysis; D006874:Hydrostatic Pressure; D008954:Models, Biological; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D011235:Predatory Behavior; D011312:Pressure; D013180:Sprains and Strains / Q000503:physiopathology*; D013314:Stress, Mechanical