Let F be a field and A a free associative F -algebra or a group algebra of a free group with an infinite set X of generators. We find a necessary and sufficient condition for the inclusion I ′ ⊆ I , where I = I1 . . . Ik and I ′ = I ′ 1 . . . I ′ l are any products of T -ideals in A. A canonical reformulation in terms of products of group representation varieties answers a question posed in 198...

The aim of this paper is the kinematic study of a 3-RPR planar parallel manipulator where the three fixed revolute joints are actuated. The direct and inverse kinematic problem as well as the singular configuration is characterized. On parallel singular configurations, the motion produce by the mobile platform can be compared to the Reuleaux straight-line mechanism.

This paper compares morphological and functional definitions of the flexion-extension axis using six dof electrogoniometry and bone Modelling.

Consider the square lattice Z with vertices at points with integer-valued coordinates in R = {(x1, x2)| xk ∈ R, k = 1, 2} and complex (or real) scalar fields u on the lattice Z, u : Z → C, that are defined by their values ui1i2 , ui1i2 ∈ C, at each vertex of the lattice with the coordinates (i1, i2), ik ∈ Z, k = 1, 2. Consider a class of two-dimensional discrete equations on the lattice Z for t...

We attach the degenerate signature (n,0,1) to the dual Grassmann algebra of projective space to obtain a real Clifford algebra which provides a powerful, efficient model for euclidean geometry. We avoid problems with the degenerate metric by constructing an algebra isomorphism between the Grassmann algebra and its dual that yields non-metric meet and join operators. We focus on the cases of n=2...

In this paper we address the problem of creating accurate joint models from real motions while allowing scalability. We propose an automatic method to model, scale and simulate non-idealized joints from the external motion of markers. We demonstrate the method on the human knee joint modeling for musculoskeletal analysis and for character animation. The resulting joints, called correlative join...

This study provides insight into the ways computers and technology can help athletes and instructors improve performance by capturing 3D information about human skeletal kinematics during physical activity. We explore current methods being applied and look at possible technological improvements for the future.

Let S be a skewfield. If J and / ' are submodules of 2 such that the nonzero elements of J are the inverse elements of those of J , then J and J' form a "pair of inverse modules." A module admitting an inverse module will be called a /-module and a selfinverse module containing 1 will be called an 5-module. In an earlier paper the author has shown that if S is a (commutative) field of character...

–In virtual human modeling, the shoulder is usually composed of clavicular, scapular and arm segments related by rotational joints. Although the model is improved, the realistic animation of the shoulder is hardly achieved. This is due to the fact that it is difficult to coordinate the simultaneous motion of the shoulder components in a consistent way. Also, the common use of independent 1-DOF ...

In this paper, we present SimHuman, a platform for the generation of real-time 3D environments with virtual agents. SimHuman is highly dynamic and configurable, as it is not based on fixed scenes and models, and has an embedded physically based modelling engine. Its agents can use features such as path finding, inverse kinematics and planning to achieve their goals. The paper explains in detail...