THE EFFECT OF 3D TECHNOLOGIES IN STEREOMETRY TRAINING

The software proposed in the report can be used as a technological tool in the teaching and learning of the discipline of stereometry. The aim is to improve the learning process by supporting the development of students’ creativity and spatial imagination, qualities needed in the study of spatial geometric bodies. A new boundary method is used in the generation of geometric objects. This new method uses elements of the Cavalieri Indivisible method and Isaac Newton's boundary method, thus achieving higher accuracy with respect to generated objects compared to 3D systems that use the rules of trigonometry in the construction of geometric bodies. This article performs a comparative analysis between a traditional and a new method for generating 3D geometric objects according to certain parameters and criteria. The new method involved in the analysis was proposed by the author of the report. While the traditional one is based on trigonometry. Two parameters were studied, one for accuracy in generating objects, and the second determining speed. In order to generate cylindrical bodies, are used the quadratic Bézier curve and the 3D modeling technique known as an extrusion, which transforms two-dimensional objects into three-dimensional ones.. One way to generate a prism and pyramid is by extruding polygons. This report presents a new way of constructing edged bodies. The considered technique for 3D modeling participates in the analysis of the studied methods.

Development and Use of a Stereoscopic System in Stereometry Training

This article briefly presents how the StereoMV mathematical software is designed and used. It consists of five modules: interface, stereoscopic visualization, stereometry, training module and knowledge testing module. The stereoscopic system is research-oriented and designed for the presented modules. The purpose of the system is to allow students to control, observe and manipulate geometric shapes in space. StereoMV is part of a dissertation on the following topic: “Stereoscopic Training System”. A new boundary method, created by the author of the system, is used to generate geometric shapes. This method takes part in the generation of a circle by means of a quadratic Bézier curve using three control points. The use of the matrix calculus, which plays a role in the generation of geometric shapes and the performance of transformations, is of particular importance in the development of the system.

Design of Powered Ankle-Foot Prosthesis With Nonlinear Parallel Spring Mechanism

In this paper, a powered ankle-foot prosthesis with nonlinear parallel spring mechanism is developed. The parallel spring mechanism is used for reducing the energy consumption and power requirement of the motor, at the same time simplifying control of the prosthesis. To achieve that goal, the parallel spring mechanism is implemented as a compact cam-spring mechanism that is designed to imitate human ankle dorsiflexion stiffness. The parallel spring mechanism can store the negative mechanical energy in controlled dorsiflexion (CD) phase and release it to assist the motor in propelling a human body forward in a push-off phase (PP). Consequently, the energy consumption and power requirements of the motor are both decreased. To obtain this desired behavior, a new design method is proposed for generating the cam profile. Unlike the existing design methods, the friction force is considered here. The cam profile is decomposed into several segments, and each segment is fitted by a quadratic Bezier curve. Experimental results show that the cam-spring mechanism can mimic the desired torque characteristics in the CD phase (a loading process) more precisely. Finally, the developed prosthesis is tested on a unilateral below-knee amputee. Results indicate that, with the assistance of the parallel spring mechanism, the motor is powered off and control is not needed in the CD phase. In addition, the peak power and energy consumption of the motor are decreased by approximately 37.5% and 34.6%, respectively.

Quick draw of the original handwriting base on quadratic Bezier curve

According to the use of normal mouse as an input device to achieve the quick draw of the original handwriting, this paper proposed a quick draw Method of original handwriting based on quadratic Bezier curve. Firstly, the method obtained moving speed and the direction information of the mouse and the information helped to obtain the periphery polygon vertex of the original handwriting drawing. Then Corresponding vertices of a polygon was used to structure the Bezier curve on both sides of the original handwriting to generate the peripheral curve polygon of the original handwriting. Finally, it was input by filling the curve polygon to simulate the user’s handwriting. The experimental results show that the algorithm interacts smoothly and has good simulation effect. Compared with other original handwriting drawing methods with the help of the related electronic input devices, this method only needs the normal mouse instead of stylus and multi touch device to achieve the smooth drawing of original handwriting. Therefore it has wide application value.

The Application of Quadratic Bezier Curve on Rotational and Symmetrical Lampshade

The procedure of constructing lampshade is through parameter merger and selection of Bezier surfaces shapeshifters; thus it producesperfect and varied sitting-lampshades.Constructing sitting-lamp shades requires the study of the physical (lighting) and geometryaspects. In terms of geometry, the existed sitting-lampshade creation models is generally monotonous and constructed from objects pieces. In line with these problems, this research is divided into four stages:First, preparing the data to build a sitting-lampshade. Second, technical studying to construct the symmetricity of the sitting-lamp shade shape.Third, constructing the parts of the sitting-lampshade, namely the base, the main part, the roof. Fourth, constructingthe complete sitting-lampshade. The results of this research to obtain the procedures of constructing the sitting-lampshade namely: First, dividing the major axis into three non-homogeneous sub segments.Second, constructing parts of the sitting-lampshade namely the base, the main part, and the roof by combining the sitting-lamp shade components from the geometrical objects deformation.Third, filling each sub segment of non-homogeneous parts with parts of the lampshade and creating the boundary curvesproducing a varied innovative symmetricalmodels of sitting-lampshade.