POINT CLOUD MANAGEMENT THROUGH THE REALIZATION OF THE INTELLIGENT CLOUD VIEWER SOFTWARE

The paper presents a software dedicated to the elaboration of point clouds, called <i>Intelligent Cloud Viewer</i> (ICV), made in-house by AESEI software (Spin-Off of Politecnico di Bari), allowing to view point cloud of several tens of millions of points, also on of “no” very high performance systems. The elaborations are carried out on the whole point cloud and managed by means of the display only part of it in order to speed up rendering. It is designed for 64-bit Windows and is fully written in C ++ and integrates different specialized modules for computer graphics (Open Inventor by SGI, Silicon Graphics Inc), maths (BLAS, EIGEN), computational geometry (CGAL, <i>Computational Geometry Algorithms Library</i>), registration and advanced algorithms for point clouds (PCL, <i>Point Cloud Library</i>), advanced data structures (BOOST, <i>Basic Object Oriented Supporting Tools</i>), etc. ICV incorporates a number of features such as, for example, cropping, transformation and georeferencing, matching, registration, decimation, sections, distances calculation between clouds, etc. It has been tested on photographic and TLS (<i>Terrestrial Laser Scanner</i>) data, obtaining satisfactory results. The potentialities of the software have been tested by carrying out the photogrammetric survey of the Castel del Monte which was already available in previous laser scanner survey made from the ground by the same authors. For the aerophotogrammetric survey has been adopted a flight height of approximately 1000ft AGL (<i>Above Ground Level</i>) and, overall, have been acquired over 800 photos in just over 15 minutes, with a covering not less than 80%, the planned speed of about 90 knots.

Active Grasping Control of Virtual-Dexterous-Robot Hand with Open Inventor

The grasping technology of the virtual-dexterous-robot (VDR) hand plays a key role in the teleoperation of the space robot. For a grasp task in the virtual environment, the collision detection and virtual force calculation need to be implemented. Firstly, a tree-structure virtual scene including a VDR hand and a target object is built up with open inventor (OIV). Secondly, the collision manager provided by OIV is used for collision detection and the oriented bounding box (OBB) is adopted to improve the real-time performance of collision detection. Thirdly, an algorithm is proposed for calculating the virtual force by using the contact deformation. And the contact deformation is calculated according to the transformation matrix between the coordinate systems of the two contact objects. Furthermore, the contact friction is also calculated by this matrix. Considering the virtual force, the modified stable grasping conditions are proposed which are suitable for the virtual grasping. Then a method is proposed for implementing the grasp or release operation by translating different nodes in the tree-structure scene, which can avoid destroying the tree structure. Finally, the viability and effectiveness of the proposed algorithms are proved by simulation experiments.

Research on the Customized Color Mapping Technology of Reservoir 3D Display

The technology of color mapping could provide the visual representation of data mapping corresponding of the color range, in the three-dimensional visual scene. In order to analyze the characteristics of three-dimensional reservoir model more efficiently, this article researched the key technology of customized color mapping based on the Open Inventor. The MeshViz and DialogViz extended module of the Open Inventor were used to achieve the interactive legend, so the user could adjust the color mapping range dynamically, and change the data mapping mode by GUI interface. The different geological characteristics were displayed with the customized color, which would lead to a more intuitive understanding of the reservoir model.

Research on the Interactive Technology of Reservoir 3D Display

In the process of reservoir 3D modeling and display, when the data amount of the model was large, the visual model would become huge. While the oil exploration and development experts might usually pay more attention to the distribution of the cells within some layers, some areas, or some regions with specific attribute range. This article used the MeshViz and DialogViz extended module of the Open Inventor to achieve the interactive display technology including extracting slices of the 3-dimensional model and the filtering valid cells based on the specific range of the attribute value. The proposed method could extract specific slices and display the ROI region interactively, and could help the user to analyze the characteristics of three-dimensional reservoir model more efficiently.

THE GEANT4 VISUALIZATION SYSTEM — A MULTI-DRIVER GRAPHICS SYSTEM

From the beginning, the GEANT4 Visualization System was designed to support several simultaneous graphics systems written to common abstract interfaces. Today, it has matured into a powerful diagnostic and presentational tool. It comes with a library of models that may be added to the current scene and which include the representation of the GEANT4 geometry hierarchy, simulated trajectories and user-written hits and digitizations. The workhorse is the OpenGL suite of drivers for X, Xm, Qt, and Win32. There is an Open Inventor driver. Scenes can be exported in special graphics formats for offline viewing in the DAWN, VRML, HepRApp and gMocren browsers. PostScript can be generated through OpenGL, Open Inventor, DAWN and HepRApp. GEANT4's own tracking algorithms are used by the Ray Tracer. Not all drivers support all features but all drivers bring added functionality of some sort. This paper describes the interfaces and details the individual drivers.

Software Development of Large-Span Structure Hoisting on the Time-Varying Analysis

According to the time-varying analysis theory of large-span structure hoisting, the structure transformation matrix around three-dimensional translation and rotation is obtained. Based on the obtained transformation matrix, the final state matrix after structure hoisting can be described, and the structural internal force of any position can be calculated. Using the Coin3d Open Inventor that is an open source graphics development kit, developers exploited simulation software of large-span structure hoisting. The software can analyze structural security with the time-varying analysis theory, and it has been applied in the simulation of hoisting construction at the Hefei Xinqiao international airport. The results indicated the software is reliable to protect safety of structure hoisting.

Virtual Clay Modeling System with 6-DOF Haptic Feedback

This paper describes an innovative free-form modeling system, Virtual Clay Modeling System (VCMS), in which users can directly manipulate the shape of a virtual object like a clay model in real world. With this system, some disadvantages of interaction with computer aided industry design (CAID) systems can be resolved. In order to enhance the immersion feelings and improve the controlling abilities to cut, paste, and compensate of VCMS, we use Spaceball 5000 and PHANTOM Desktop to assign the set of interaction tasks. During the process of realizing 6 degree-of-freedom (DOF) haptic feedback modeling control, we developed and accomplished the device interfaces with Open Inventor and Qt application framework. VCMS provides us a good immersion of allowing for effective modeling in a virtual world.