Microconstruction Simulation Of Virtual Hoisting

Virtual Hoisting System aims to provide a virtual hoisting construction environment with high truth degree and better characteristic of intelligent interaction for constructors and managers on the site of construction, especially steel structure project. Facing a complex hoisting task, builders can complete simulation and analysis of hoisting process ahead, and then assist real construction project.Microconstruction simulation is a new perspective to the study of virtual construction technology and plays an important role to improve the characteristic of intelligent interaction of VHS. Virtual construction machinery is a kind of complicated microindividual with outstanding intelligent interaction in the scene of microconstruction simulation. Building the prototype of it is a basic research content of microconstruction simulation and has an important significance both in theory and practice.In the research, taking prototype of virtual tower crane for example, technologies such as virtual simulation, multibody system dynamics, robotics and so on were applied synthetically to structure the prototye of virtual construction machinery. The main results of it can be summarized to the following outlines:(1) Concepts of microconstruction and microconstruction simulation were proposed. An architecture of supporting technologies of microconstruction simulation was structured. A feasible software development scheme was raised and an experimental platform of virtual hoisting simulation was built initially based on EON Professional 6.0, EON is an advanced development platform of virtual simulation software. The experimental platform could supply an environment for validation of feasibility and performance testing for the further research work.(2) Technology of three-dimensional modeling and optimization for virtual construction machinery was studied and a kind of method named two-stage model optimization was put forward, which depended on the modeling stage using Solidworks, 3DS Max and the performance optimization stage in EON. The results indicate that the optimized model of virtual construction machinery could satisfy the performance request of real- time rendering and image quality of virtual hoisting scene.(3) Aiming at kinematics modeling of virtual construction machinery, combining robotics, a kind of modeling method based on D-H model of robot kinematics was proposed, and the correctness and effectiveness of kinematics model acquired was validated based on VHEP. Kinematics modeling is the mathematical basis for realizing the characteristic of motion and interaction of microconstruction simulation of virtual hoisting, and laid the foundation for achieving autonomous hoisting simulation at the same time.(4) In order to improve the efficiency of dynamics simulation of virtual construction machinery in the scene of microconstruction simulation, a kind of componentized method of dynamic modeling with systematicness, reusability and extendibility was raised, and then was achieved based on dynamics module of EON Professional 6.0. Modeling and simulation methods for wirerope, which is a kind of flexible body, were proposed and the simulation effect of flexibility and stretching deformation was realized. Based on dynamics analysis of hoisting condition, the goods leaves the ground moments, simulation of cable breaking was achieved.(5) Combining analysis of collision features in real hoisting scene with characteristic of simulation tree of EON Professional 6.0, collision detection strategies based on bounding volume and hierarchical bounding volumes for virtual hoisting scene and virtual construction machinery were put forward and realized by collision module of EON Professional 6.0. In order to further improve the speed of collision detection of virtual construction machinery, a kind of collision detection algorithm named CollisionDecHuffman based on Huffman tree structure was proposed, and the storage structure for Huffman tree was designed to improve algorithm performance.(6) To enhance intelligent characteristic of virtual construction machinery, hoisting path planning and simulation of autonomous hoisting for virtual hoisting machinery were researched. An improved QuickGuess algorithm was proposed for hoisting path planning, integrating PRM algorithm of robotics, and the results indicate that improved algorithm could plan more real hoisting path successfully. Meanwhile, simulation of autonomous hoisting for virtual tower crane was achieved based on VHEP.(7) Realizing the personalized building of virtual scene is a basic research work for improving the interactive characteristic of microconstruction simulation of virtual hoisting. Two kinds of user interface were designed, meanwhile, a software development scheme was put forward based on Prototype technology and Dynamic Load technology of EON, and the feasibility of proposed scheme was validated.