Research On 3D Model Designing Methods For Ordinary Users

Designing 3D models is one of the most fundamental topics in computer graphics.3D model design tools are widely adopted in various fields,including computer-aided manufacturing,product design and film industry.With the increasing popularity of 3D printing technologies,the demand of designing customized 3D models for personal fab-rication grows rapidly.However,ordinary users lack professional knowledge and skills,required in modern 3D design softwares.Therefore,developing intuitive and easy-to-use design tools for ordinary users becomes a hot research topic in recent years.In this dissertation,we conduct research on 3D design tools specially tailored for ordinary users,including interactive user interface,simulation integration and optimiza-tion:·We propose a surface-based interior voids generation algorithm,which is used to design models of specific mass distributions.Our method relates the optimiza-tion objective to a virtual velocity field using Eulerian Semi-derivative,and finds the optimized interior voids by iteratively evolving its boundary in this velocity field.We propose a novel application of floating object design,and also apply our method to design statically balanced objects and spinnable objects.·We present an automatic algorithm for generating interior voids that not only sat-isfy functional purposes but also are support-free during 3D printing.We vox-elize the 3D model using rhombohedron voxels and parameterize common vol-ume integrals over each voxel.Based on such voxelization and parametrization-our method obtains the structure of the interior voids via alternating optimization and voxel merging.We apply our algorithm to design statically balanced models and spinnable models,and fabricate real objects for physical validation.·We present an agile simulation-aided shape editing system for personal fabrica-tion,which employs a domain decomposition framework as a unified interface for shape editing,FEM system updating and shape optimization.By parameterizing entries of the stiffness matrix and devising a local update scheme for the FEM system,our system provides users interactive structure analysis feedback during shape editing.Our system can also perform shape optimizations to reduce high stresses in model,while preserving the original appearance.·We present a sketch-based editing system for enriching rotational motions in key-frame animations.Given a set of keyframed orientations of a 3D model,our system allows the user to edit its angular velocity trajectory by sketching curves,and then computes the altered rotational motion by solving a curve fitting problem.The solved rotational motion not only satisfies the orientation constraints at the keyframes,but also fits well the user-specified angular velocity trajectory.