The present article presents a method for assessing the radial stiffness of nitinol stents. An idealized stent model was created, and its radial stiffness was calculated by means of finite element modeling. The calculations were validated against experimental measurements. The variation of radial stiffness with geometrical dimensions was calculated, and the effect of increasing radial stiffness...

Dynamic interaction between two bodies, where one is significantly more flexible than the other, is common (e.g. rotor-casing contact). This paper presents a linear model for simulating contact between rigid and flexible bodies. The motion between contacts is predicted by modal superposition, using separate models for the two components. During contact, the models are coupled via a linear conta...

Humans demonstrate an impressive ability to manipulate fragile objects without damaging them, graciously controlling the position of hands and tools while managing contact forces as necessary for the task. Robot control has been characterized by position control with the aim of producing fast, accurate and repeatable motion. These capabilities have reached a level where robots often outperform ...

While the spring-like leg behavior of legs in mammalian locomotion has been well documented, its neural basis remains ambiguous. The purpose of the present study was to examine leg stiffness control during hopping. Seven male subjects performed in place two-legged hopping at their preferred frequency with two different contact times of the stance phase, preferred and short ones (PCT and SCT, re...

Wavelet transforms were compared between various simulated friction models and real stick-slip data. While simulations of several models produced stick-slip transition oscillations seen in the real data, the wavelet features of the compliant contact model with light damping best captured the characteristics of the experimental signal. The wavelet contours were also used to estimate the contact ...

the asymmetric problem of rocking rotation of a circular rigid disk embedded in a finite depth of a transversely isotropic half-space is analytically addressed. the rigid disk is assumed to be in frictionless contact with the elastic half-space. by virtue of appropriate green's functions, the mixed boundary value problem is written as a dual integral equation. employing further mathematica...

1.1 Background Biomechanical Systems • Physical Knee Models • Phenomenological Mathematical Knee Models • Anatomically Based Mathematical Knee Models 1.2 Three-Dimensional Dynamic Modeling of the Tibio-Femoral Joint: Model Formulation Kinematic Analysis • Contact and Geometric Compatibility Conditions • Ligamentous Forces • Contact Forces • Equations of Motion 1.3 Solution Algorithm DAE Solvers...

We have examined the effect of surface contamination on the attenuation and stiffness of compressional seismic waves in artificial cylindrical glass cracks that are partially saturated with water. The compression of the gap perpendicularly to its plane reduces the gap volume and forces the water to redistribute within the gap (conservation of volume of an incompressible liquid). On clean surfac...