Mesh Topology Identification for Mass-Spring Models p. 50 A New Biomechanical Model Based Approach on Brain Shift Compensation p. 59 Real-Time Synthesis of Bleeding for Virtual Hysteroscopy p. 67 A Biomechanical Model of the Liver for Reality-Based Haptic Feedback p. 75 Image-Based Modelling of Soft Tissue Deformation p. 83 Individualized Geometric Model from Unorganized 3-D Points: An Applicat...

Generalized cylinder (GC) has played an important role in computer vision since it was introduced in the 1970s. While studying GC models in human visual perception of shapes from contours, Marr assumed that GC’s limbs are planar curves. Later, Koenderink and Ponce pointed out that this assumption does not hold in general by giving some examples. In this paper, we show that straight homogeneous ...

Since Euclid (300 BC) we have been used to perceiving nature with the concept of a threedimensional (3-D) geometry. We measure linear structures in one dimension, area-like structures in two dimensions, and volume-like structures in three dimensions. However, when we measure an object in terms of these three dimensions, we are aware that the geometric model describes a solid body, while a natur...

An integrated tool developed for the construction of unstructured numerical grids about complex configurations is presented. The tool is highly integrated and employs the native underlying geometry modeling kernel used to define the target domain for providing topological and geometric access used by the grid generation procedures. This access greatly reduces the overall process time required t...

ABSTRACT. A Steiner surface is the generic case of a quadratically parameterizable quartic surface used in geometric modeling. This paper studies quadratic parameterizations of surfaces under the angle of Classical Invariant Theory. Precisely, it exhibits a collection of covariants associated to projective quadratic parameterizations of surfaces, under the actions of linear reparameterization a...

Unfortunately, the sensing devices which are available for mobile robots often fail in a variety of circumstances. This is especially true of the less expensive devices such as ultrasonic and infrared range sensors. Combining data from several sensors and from a pre-stored model of the domain provides a way to enhance the reliability of a perception system. Such combination may be accomplished ...

Several researchers have investigated the role of texture as a basis for the recovery of surface orientation. Gibson 1 was the first to address the problem of recovering the orientation of a plane covered with textural elements. He assumed that the density (number of elements per unit area) of these elements is uniform. Under this assumption he observed that the density gradient in the image sp...

This paper presents a method for fitting a digital line (resp. plane) to a given set of points in a 2D (resp. 3D) image in the presence of outliers. One of the most widely used methods is Random Sample Consensus (RANSAC). However it is also known that RANSAC has a drawback: as maximum iteration number must be set, the solution may not be optimal. To overcome this problem, we present a new metho...

This chapter describes the state-of-the-art techniques for constructing photo-realistic three dimensional models of physical objects using range and intensity images. In general, construction of such models entails four steps: First, a range sensor must be used to acquire the geometric shape of the exterior of the object. Objects of complex shape may require a large number of range images viewe...

Algebraic surfaces – which are frequently used in geometric modeling – are represented either in implicit or parametric form. Several techniques for parameterizing a rational algebraic surface as a whole exist. However, in many applications, it suffices to parameterize a small portion of the surface. This motivates the analysis of local parametrizations, i.e., parametrizations of a small neighb...