Nonlinear viscoelastic oscillations of a vehicle in vertical direction excited by static imbalance are considered. When taking into account the rheological properties suspension material and spring, Boltzmann-Volterra principle was used. Mathematical models problem under consideration obtained, which described systems nonlinear integro-differential equations. A solution method based on quadratu...

The UIC Standard Suspension consists of a leaf spring (5) see the figure which rests on the axle box (6), which can move horizontally and vertically between the guidances (4). In the horizontal the guidance provides an end stop for the translations and the yaw of the wheelset (7). In the vertical direction the motion of the wheelset is restricted by the leaf spring with its nonlinear dry fricti...

We study the nonlinear oscillations of a forced and weakly dissipative spring– magnet system moving in the magnetic fields of two fixed coaxial, hollow induction coils. As the first coil is excited with a dc current, both a linear and a cubic magnet-position dependent force appear on the magnet–spring system. The second coil, located below the first, excited with an ac current, provides the osc...

To compute dynamic characteristics of nonlinear viscoelastic springs with elastic structures having huge degree-of-freedom, Yamaguchi proposed a new fast numerical method using finite element method [1]-[2]. In this method, restoring forces of the springs are expressed using power series of their elongation. In the expression, nonlinear hysteresis damping is introduced. In this expression, nonl...

This research deals with the nonlinear material and geometric behaviors of reinforced concrete deep beams resting on linear or nonlinear Winkler foundation. The finite elements through ANSYS (Release-11, 2007) computer software are used. The reinforced concrete deep beam is modeled using (SOLID 65) 8 node brick element and the soil is modeled using linear spring (COMBIN 14) element or nonlinear...

In this work, a system consisting of a main structure with a nonlinear tuned vibration absorber having a hardening spring attached to it is considered. The nonlinearity in the absorber's spring is a cubic nonlinearity and is obtained by attaching two additional, relatively soft, similar linear springs to the absorber's mass. These added springs are attached to the absorber's mass in such a way ...

An articulated leg for the use in a running robot is presented. It is driven by series elastic actuation with a highly compliant spring at the knee joint to exploit periodic energy storage and passively support a running motion. The spring is connected with the knee motor by a cable pulley system, which allows the advantageous placement of the motor in the hip joint and enables us to use a comp...

Subject to a voltage, a dielectric elastomer can deform substantially, making it a desirable material for actuators. Designing such an actuator, however, has been challenging due to nonlinear equations of state, as well as multiple modes of failure, parameters of design, and measures of performance. This paper explores these issues, using a spring-roll actuator as an example. We formulate the e...

In this work we have proposed an improvement in the shape of the V-shaped microcantilever by varying the width profile. In this paper we have studied the variation of resonant frequency as a function of changes in profile determined by the length of the microcantilever, keeping constant the active area for binding. It is observed that for the optimized nonlinear profile the angle at the tip is ...