The Research On The Key Technologies Of The Crane Simulating Training System

Virtual Reality (VR) is a kind of advanced, natural and intuitional human-computer technology, which provides users multi-sense such as vision, hearing and feeling. VR technology supports users to interact with models in the computer and gives them experience just like with the realistic models. With the rapid development of computer technology, VR technology is studied further and is used more widely.The Simulating Training System is a kind of advanced simulation system which is integrated of many sophisticated technologies such as sensor technology, computer interface technology, 3D real-time animation technology, artificial intelligence technology, data communication technology, network technology, multimedia technology, and so on. It is not only low-energy, safe and economical, but also has no limitations of time, climate and working space for training activities. By the aid of 3I characters (Immersion, Interaction, Imagination) of VR technology, users can be immersed in the virtual environment, receive the drawbacks of vision, hearing and feeling, sense the structure of the manipulated objects and their working principles, image their operating items, experience all kinds of working conditions which usually or seldom occur in the real world, and then acquire better training effect.Crane is a kind of general logistics and transport equipment, which is widely used in metallurgy, manufacture, ports, hydropower, construction and other industries. At the same time, crane is also a kind of special equipment, so its operators must undergo strict theory study and operating practice of safety technology, and only after passing the examination, can they receive relative certifications and be permitted to work as crane's operators. Currently, practice and examination program of crane's operator training is mostly processed in the crane at a hired factory. Although this approach will enable the trainees to receive direct training experience, there are also a great of potential safety problems. In addition, its training resources are constrained, its energy is wasted greatly, its examination is lack of objectivity, its training effect is unsatisfying, and so on. All these has brought great challenges over the current training work of crane's operators. Researching and developing excellent and powerful crane simulation training system and using it in the operators' training is the most effective methods to meet this challenge. This thesis is just based on this background and takes on the relative studies.This thesis aims at the special requirements of crane operators' training, analyzes the characteristics and components of the crane simulation training system, establishes a new training framework integrated skills training and theory studying. Apart from that, it also studies systematically and deeply on the theory and method of modeling, texture special effects, performance optimization technology, modeling of movable virtual human and its free deformation method, suitable visual displaying method for the crane training environment, manipulation-oriented human-computer interaction technology, etc. The thesis shows great theoretical meaning and practical value. The main work (include achievements and innovations) finished in the thesis are:1. A new training framework of simulation training system is proposed. And the thesis illustrates that simulation training system should not only has the function of simulating operation, but also has teaching function for theoretical knowledge. Structure of the system is given by the terms of requirements of crane operators' training. Visual scene models with multi-level are suggested to be used to satisfy different training purposes.2. Research on modeling method for crane's virtual scene based on geometric features. Some different modeling strategies are adapted in accordance with structure features of the cranes and a scene with multi-leveled models including bridge, crab and hook group is build up. Parameterized virtual modeling for box girder is implemented based on template files, which resolves the rapid modeling problem for serialized box structures. Some proto nodes for typical shape material are designed by terms of object-oriented technology and can be used to realize convenient and fast modeling for shape materials.3. Research on texture special effects and performance optimization technology. Truss structure modeling based on the simple modeling nodes and texture mapping technology is realized by using image with transparency information. Movable illumination effects in the box girder are achieved based on multi-texture technology. Research on the optimization technology for VRML scenes is conducted from three aspects of the file optimization, model optimization and texture optimization. Organize and manage method with Bsp-tree is adapted and can control the number of rendering triangles effectively.4. Research on virtual human modeling method based on skeleton. Combined with international standard of human joints which named H-Anim and its four joint levels, the movement of joints can be controlled by interpolation algorithm. FFD technology is applied and can make human's waist deform.5. Considering both visual and manipulating aspects, some human-computer interaction technology is studied. By analyzing several currently-used visual displaying schemes for crane's simulation training, a display concept based on enhanced virtuality is proposed and some key issues in it are discussed. Manipulation based human-computer interaction technology is studied and two typical virtual controller are realized by associating the time or the location parameter of modeling with its movement parameters. A implement method of physical controller is presented based on virtual keyboard mapping technology and a compact and flexible control box prototype is obtained. Using it, users can operate the virtual crane conveniently.This thesis do not and can not contain all the problems of crane simulation training system, but we hope relative theory and methods can be studied and developed continually based on the work discussed above. We also hope that the crane simulation training system can be practical as soon as possible.