Study on Physically-Based Methods for Assisting Interactive object Layout

点击翻译按钮获取中文摘要

Most mechanical products can be considered as a collection of rigid objects properly configured in a three dimensional space. They realize their function by transferring forces and motions through contact relations between the component objects. The purpose of our study is to develop fast computation algorithms for analyzing these dynamic interactions and their effects on the mechanical behavior of the product.The following three results are obtained in our study.1. Tolerance analysis Any machine parts have geometric deviations due to their production. They cause various functional uncertainties of mechanical products. Designers control the effect of the deviations by specifying proper tolerances on the parts. We develop an algebraic algorithm for analyzing position uncertainties of two parts in an assembly if certain shape variations of individual parts are allowed by tolerances.2. Efficient collision detection Many tasks in machine design and manufacturing activities can be formulated as layouting of solid objects in a spatial region. Component parts of a precise mechanical product are very tightly placed in a small spatial region, therefore possible pairs of parts to contact are usually limited. Based on this characteristic of mechanical products, we develop some efficient algorithms for detecting and avoiding collisions between the parts.3. Robust geometric computation Numerical data describing the solid geometry are usually given using floating point numbers. Since floating point numbers are basically approximations, there may be imprecision that leads to inconsistencies about the represented object. Some types of the inconsistencies can be avoided by using tolerance ideas of the mechanical design field. Based on this concept, several tolerance based algorithms for stable geometric processing are developed.