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This paper is focused on solving the problem of the 2D compressible subsonic fluid flow around an obstacle using BEM with higher order boundary elements, with special consideration regarding to the treatment of singulatities. The 2D problem of a compressible fluid flow around an obstacle is equivalent with a singular boundary integral, obtained in terms of primary variables of the problem, the components of the velocity field. This singular boundary integral equation is solved by using quadratic isoparametric boundary elements. The problem is finally reduced to a linear system of equations. Aspects regarding the evaluation of the matrix coefficients are presented and a special attention is given to the treatment of integrals of singular kernels. A method based on the definition of the Cauchy Principal Value of an integral is developed. The method described is implemented into a computer code made in MathCAD and numerical results are obtained for different types of obstacles. We validate the computer through an analytical checking, made by comparing the numerical results with the exact solutions that exist in some particular cases, which are in very good agreement. [ABSTRACT FROM AUTHOR]

The paper presents a virtual reality techniques to create and to simulate a skeletal model of human upper limbs. Motions supported by the current version of the system are: arm flexion/extension, arm adduction / abduction and forearm flexion/extension. It's present the differences between VRML and Matlab. A computer system has been developed where a set of forces done by the muscles are parameterized and the limb motion animation, in real time, is achieved through biomechanics equations. [ABSTRACT FROM AUTHOR]

The paper presents an application of the Complex Variable Boundary Element Method (CVBEM) to solve a boundary value problem over two-dimensional multiply connected regions, in fact for the problem of a potential fluid flow around objects. The CVBEM is a powerful numerical tool for solving generally two-dimensional boundary value problems in which appear complex functions, and it represents a numerical application of Cauchy Integral Theorem. For solving the boundary integral the problem is reduced at there can be used different kinds of boundary elements. In this paper there are used linear boundary elements, so the geometries involved are approximated by polygonal lines and for the approximation of the unknowns there are used linear basis functions. The CVBEM's advantage over other techniques, pointed out by the present paper, is the fact that when this method is applied the approximation exactly solves the equation, so using this method good approximations can be found. A computer code based on this method is developed and numerical results are obtained for some particular cases. [ABSTRACT FROM AUTHOR]

This paper presents a solution of the singular boundary integral equation of the 3D compressible fluid flow around an obstacle, which uses isoparametric linear boundary elements of Lagrangean type. The singular boundary integral equation formulated in velocity vector terms is deduced by applying the indirect technique of the BEM with sources distribution. The problem is reduced to a linear system of equations and for evaluating the coefficients arising from integrals of singular kernels a suitable parametric representation is used and the finite part of the integrals involved is considered. Based on the method exposed a computer code in MATHCAD is made. We test the method solving the problem in a particular case, in which an exact solution is known. A comparison between the exact solution and the numerical one shows a high degree of accuracy. [ABSTRACT FROM AUTHOR]

The paper presents the analysis of human arm joints is carried out and the study is extended to the robot manipulator. This study will first focus on the kinematics of human upper arm which include the movement of each joint in shoulder, wrist, elbow and fingers. Those analyses are then extended to the design of a human robot manipulator. A simulator is built for Direct Kinematics and Inverse Kinematics of human upper arm. In the simulation of Direct Kinematics, the human joint angles can be inserted, while the position and orientation of each finger tips (end-effector) are shown. The simulation of human arm forward kinematics is performed through MATLAB Graphical User Interface and VRML. tained from kinematics analysis, the human manipulator joints can be designed to follow prescribed position trajectories. [ABSTRACT FROM AUTHOR]

The paper presents a dynamic model considering the human upper limb as a mechanic system with 6 degrees of freedom where the segments are moved by their own weight forces. The bones were modeled in Solid Works, the model of the upper limb obtained being very close as form to the real one. Based on this model, the calculus of mass proprieties was made. The differential equations of velocities obtained were solved using Lagrange formalism with help of Matlab programs. A dynamic model must provide a good approximation of total weight and mass distribution as well as transmissibility and amortization proprieties for bones, muscles and joints. [ABSTRACT FROM AUTHOR]