Virtual surgery simulation system is a typical application of virtual reality technology in the medical field. Firstly, in order to select a suitable way for real-time deformation and force feedback algorithm, after compared several classical numerical integration algorithm, we select the mid-point method as the deformation algorithm in this paper. The feedback force calculation is based on a s...

Trotting, bipedal running, and especially hopping have long been considered the principal bouncing gaits of legged animals. We use the radial-leg spring constant [Formula: see text] to quantify the stiffness of the physical leg during bouncing gaits. The radial-leg is modeled as an extensible strut between the hip and the ground and [Formula: see text] is determined from the force and deflectio...

We present a new approach for realistic visio-haptic simulation of nonlinear and viscoelastic behavior of an organ tissue using a particle model. The spring and damper coefficients of the particle model are calibrated using a derivative-free optimization technique such that its behavior mimics the behavior of a corresponding finite element (FE) model. In our approach, we first conduct static in...

In this paper we present a newmethod for approximating non-linear dynamics in deformable simulations based on a full cubic polynomial formulation of the inter-particle force. The proposed approach is a non-physical extension of the well known St Venant Kirchhoff force, focusing on practical considerations about the behavior of the deformable model. Therefore it is very useful for simulating and...

This paper is concerned with a real-time method for realizing virtual destruction of a 3D object with external force. A target object is a soft tofu (bean curd) cube which is easily destructable or breakable with a stick. A spring-mass network model is used to represent such an object. Destruction is realized by cutting a spring when its length exceeds its maximum length due to excess stretch f...

This paper deals with the problem of the instability regions of a free-free uniform Bernoulli beam consisting of two concentrated masses at the two free ends under the follower and transversal forces as a model for a space structure. The follower force is the model for the propulsion force and the transversal force is the controller force. The main aim of this study is to analyze the effects of...

A motion based approach to generating vertical ground reaction forces (VGRF) from the motion of sprint running could be a useful analytical tool. The spring-mass model has been used for this purpose; however, the invariant pattern predicted by the model is not fully consistent with the force-time waveforms of competitive sprint athletes. The recently introduced two-mass model provides an altern...

Maneuverable, high aspect ratio poly(3,4-ethylene dioxythiophene) (PEDOT) fibers are fabricated for use as cellular force probes that can interface with individual pseudopod adhesive contact sites without forming unintentional secondary contacts to the cell. The straight fibers have lengths between 5 and 40 μm and spring constants in the 0.07-23.2 nN μm(-1) range. The spring constants of these ...

This paper discusses the dynamic error characteristics of touch trigger probes used with coordinate measuring machines. During the investigation, a number of important parameters have been identified, including measurement speed, probe longitude, approach distance, probe latitude, stylus length/stylus tip diameter, probe orientation, operating mode (scanning and nonscanning), scan pitch, preloa...

An actuation method for atomic force microscope ~AFM! cantilevers in fluids is reported. The radiation pressure generated by a focused acoustic transducer at radio frequency ~rf! ~100–300 MHz! exerts a localized force of controlled amplitude at a desired location on the AFM cantilever. This force can be used to measure the spring constant and other dynamic properties of the cantilever. Furtherm...