This paper presents a new method for real-time modelling soft tissue deformation. It improves the traditional mass-spring model with conical springs to deal with nonlinear mechanical behaviours of soft tissues. A conical spring model is developed to predict soft tissue deformation with reference to deformation patterns. The model parameters are formulated according to tissue deformation pattern...

Internally-balanced Magnetic Unit (IB Magnet) has been developed as a fundamental technique of wall climbing robots. This unit comprises of a permanent magnet which generates a strong sticking force, and a spring unit which cancels the internal force so that the unit can provide easy sticking and releasing actions. In this paper, the authors aim to enlarge usefulness of IB Magnet by several app...

In this paper we present a cable mechanism that realizes a nonlinear rotational spring from a linear translational spring. The spring is pulled by a cable wound around a non-circular spool, which is rigidly attached to the joint. The non-circular shape of the spool induces a nonlinear relationship between its angular position and the torque created by the tension of the cable. Depending on the ...

We consider a class of differential models of viscoelastic fluids with diffusive stress. These constitutive models are motivated by Peterlin dumbbell theories with a nonlinear spring law for an infinitely extensible spring. A diffusion term is included in the constitutive model. Under appropriate assumptions on the nonlinear constitutive functions, we prove global existence of weak solutions fo...

Design of haptic systems that guarantee stable interaction is a challenging task. Virtual environments are typically highly nonlinear—resulting in a nonpassive discrete-time model. This paper will investigate how nonlinear mass/spring/damper virtual environments can be designed to guarantee the absence of oscillations and other chaotic behavior in the signal presented to the human operator. In ...

In our previous research, as the first step to realize a new SelfOrganizing Map model, we have proposed a simple one dimensional 2-neuron model connected by a nonlinear spring. This study proposes one dimensional 3-neuron model connected by a nonlinear spring in order to represent a relationship between the winner and its neighboring neurons in SOM algorithm. Furthermore, we consider two kinds ...

The feasibility of reconstructing total spring precipitation for the South Platte River basin from treering chronologies using artificial neural networks is explored. The use of artificial neural networks allows a comparison of reconstructions resulting from both linear and nonlinear models. Both types of models produced reconstructions that explained more than 40% of the variation in spring pr...

In this paper, we study the nonlinear response of the nonlinear mass-spring model with nonsmooth stiffness. For this purpose, we take as prototype model, a system that consists of the double-well smooth potential with an additional spring component acting on the system only for large enough displacement. We focus our study on the analysis of the homoclinic orbits for such nonlinear potential fo...