A new fail-safe, variable stiffness, and variable damping isolator (VSDI) device is designed, developed and tested utilizing magneto-rheological elastomers (MREs). This system provides a simultaneous controllable stiffness and damping. The performance of the VSDI is investigated experimentally under dynamic shear loads. The results demonstrate that this VSDI is capable of increase of stiffness ...

Static stiffness measurement of precision bearing components by influence coefficients is complicated by the task of loading and measuring the baseline test fixture stiffness before including the bearing components. Furthermore, as the displacement of the bearing system is measured for various load conditions, the stiffness of high quality bearings may be difficult to distinguish from the test ...

Stability of the spinal column is critical to bear loads, allow movement, and at the same time avoid injury and pain. However, there has been a debate in recent years as to how best to define and quantify spine stability, with the outcome being that different methods are used without a clear understanding of how they relate to one another. Therefore, the goal of the present study was to directl...

PURPOSE To assess the mechanical ability of the inferior oblique neurofibrovascular bundle (NFVB) to act as an ancillary origin for the inferior oblique muscle after anterior transposition. METHODS Stress-strain relations and Young's modulus of elasticity, a measure of tissue stiffness, were determined for the NFVB in vitro, in situ, and in vivo in dynamic and static conditions. For compariso...

Design and development of vertically-suspended water pumps requires good understanding of the rotor system characteristics with water-lubricated rubber bearings (WLRB). This paper presents a newly-built experimental device to simulate rotor systems with WLRBs, and some initial results on experimental identification of dynamic stiffness coefficients of a long WLRB. In experiments, unbalanced mas...

This paper presents the influence of non-linearity on the dynamic response of floating pile foundation subject to vertical vibration. A detailed theoretical investigation of stiffness and damping parameters is made for floating piles with different shear modulus reduction ratio of the weak zone soil. The accuracy of the non-linear analysis for predicting the dynamic response depends upon the ch...

A 3-dimensional computer model of sustained bipedal walking is presented. It is intended be used as a development tool for walking controllers. The direct dynamic simulation has 8 segments, 19 degrees of freedom and is driven by prescribed joint moment and stiffness trajectories. Limited feedback in the form of a proportional-derivative controller provides upper body stability and allows walkin...

Dynamic performance of suspension seats depends on characteristics of both the suspension and the seat cushion. The objective of this study is to develop a hybrid method based on the concept of co-simulation between multibody dynamic and finite element models. The methodology is illustrated via simulating a dynamic stiffness test of a seat cushion. The dynamic stiffness of a cushion was measure...

A dynamic nonlinear model of rubber absorber in railway fastening is proposed in this paper based on a superposition principal demonstrating that the restoring force of rubber components consists of an elastic force and a damping force. In order to determine model parameters and verify the accuracy of this model, a dynamic experiment is designed. The obtained simulated results show good agreeme...