Shape manipulation using physically based wire deformations

This paper develops an efficient, physically based shape manipulation technique. It defines a 3D model with profile curves, and uses spine curves generated from the profile curves to control the motion and global shape of 3D models. Profile and spine curves are changed into profile and spine wires by specifying proper material and geometric properties together with external forces. The underlying physics is introduced to deform profile and spine wires through the closed form solution to ordinary differential equations for axial and bending deformations. With the proposed approach, global shape changes are achieved through manipulating spine wires, and local surface details are created by deforming profile wires. A number of examples are presented to demonstrate the applications of our proposed approach in shape manipulation

A Revisit of Shape Editing Techniques: from the Geometric to the Neural Viewpoint

3D shape editing is widely used in a range of applications such as movie production, computer games and computer aided design. It is also a popular research topic in computer graphics and computer vision. In past decades, researchers have developed a series of editing methods to make the editing process faster, more robust, and more reliable. Traditionally, the deformed shape is determined by the optimal transformation and weights for an energy term. With increasing availability of 3D shapes on the Internet, data-driven methods were proposed to improve the editing results. More recently as the deep neural networks became popular, many deep learning based editing methods have been developed in this field, which is naturally data-driven. We mainly survey recent research works from the geometric viewpoint to those emerging neural deformation techniques and categorize them into organic shape editing methods and man-made model editing methods. Both traditional methods and recent neural network based methods are reviewed

High Speed Cylindrical Roller Bearing Analysis, SKF Computer Program CYBEAN. Volume 1: Analysis

The CYBEAN (CYlindrical BEaring ANalysis) program was created to detail radially loaded, aligned and misaligned Cylindrical roller bearing performance under a variety of operating conditions. The models and associated mathematics used within CYBEAN are described. The user is referred to the material for formulation assumptions and algorithm detail

Patient-specific outcome simulation after surgical correction of Pectus Excavatum: a preliminary study

Although minimally invasive Nuss procedure is frequently performed to correct Pectus Excavatum, the successful aesthetical outcome is not always ensured. Using the computed tomography (CT) data of six patients, high-quality surfaces of the anterior chest wall were generated, alongside with a personalized corrective-bar. Through finite element method (FEM), replicating the surgical procedure, a simulation of the anterior chest wall correction was conducted. The assessment of this methodology was verified by comparing the metrics from the real meshes (3D scanned before and after surgery) and simulated meshes (obtained before and after FEM). Results show a mean difference of 2.85 +/- 5.77 mm on the point of maximum correction between simulated and real outcomes. No statistical differences were found (p = 0.281). High aesthetical similarity was observed concerning simulated and real outcomes. The proposed methodology presents a patient-specific simulation that may be used to plan, predict and improve the surgical outcome of the Nuss procedure. Further studies should continue to improve the presented methodology.This work has been funded by FEDER funds, through the Competitiveness Factors Operational Programme (COMPETE), and by National funds, through the Foundation for Science and Technology (FCT), under the scope of the projects POCI-01-0145-FEDER-007038; NORTE-01-0145-FEDER-000013; and NORTE-01-0145-FEDER-024300, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER). Joao Gomes-Fonseca was funded by FCT under the Ph.D. grant PD/BDE/113597/2015

Aeronautical Engineering: A special bibliography with indexes, supplement 54

This bibliography lists 316 reports, articles, and other documents introduced into the NASA scientific and technical information system in January 1975

Simulation of the postoperative trunk appearance in scoliosis surgery

Persistence of external trunk asymmetry after scoliosis surgical treatment is frequent and difficult to predict by clinicians. This is a significant problem considering that correction of the apparent deformity is a major factor of satisfaction for the patients. A simulation of the correction on the external appearance would allow the clinician to illustrate to the patient the potential result of the surgery and would help in deciding on a surgical strategy that could most improve his/her appearance. We describe a method to predict the scoliotic trunk shape after a spine surgical intervention. The capability of our method was evaluated using real data of scoliotic patients. Results of the qualitative evaluation were very promising and a quantitative evaluation based on the comparison of the simulated and the actual postoperative trunk surface showed an adequate accuracy for clinical assessment. The required short simulation time also makes our approach an eligible candidate for a clinical environment demanding interactive simulations.CIHR / IRS