Research On Three-freedom Robot Avatar Model And Its Application

With the appearance of avatar theory and the development of Human Body Modeling, people begin to immerge into the virtual reality world and apply the three-dimension avatar to interact with virtual environment.Based on the research of the H-anim Format Human Model, this dissertation extends the concept of avatar to the study of robotics, chooses the three-freedom flexible robot as the research object and constructs an avatar model of robot in the virtual environment with virtual reality modeling language (VRML). The avatar of robot becomes the leading actor instead of the real robot, just as the avatar of human body.Comparing the avatar of human body to the avatar of Three-freedom flexible robots on structure in order to find the similarity between them, this dissertation chooses multi-joint model which is mostly used for the human model to construct the robot avert of robot. In the course of building the geometric model of robot, this dissertation applies the coordinate transformation of VRML to realize the nested connection in order that the following joints can rotate while a certain joint rotates.The concept of the robot avatar makes the virtual robot model separate from the virtual environment. It is not a component of the virtual environment any longer, but a self-governed individual. As the leading role in the virtual environment, the communication between the robot avatar and the users who are out of the virtual environment is realized by the interaction between them. For the limitation of interaction that VRML provided, this dissertation uses Java to extend the ability of VRML so that more complex interaction can be realized, after discussing several VRML-based interaction technologies. This dissertation deduces the restriction equation about the angle value of all joints, and then realizes the simultaneous movement of all joints of robot by the External Authoring Interface (EAI).It is a particular application in the area of robot studies that applying the avatar on the system of web-based tele-operation. On one side, this dissertation uses the avatar of 3-DOF robot in the field of visual feedback and builds the virtual three-dimension avatar of 3-DOF robot in the virtual environment. Then, the avatar of robot can repeat the movement that the remote robot does timely and smoothly. Because the huge data of real image is replaced by the position information sent from the remote robot, and the data of position are usually too small to cause delay during transmission, the effect of visual feedback is smooth and real time.On the other side, the system can make the operator achieve the goal of a remote control of a controlled object in real world, through the mutual reaction between operator in real-life word and robot avatar in virtual environment. Users can control the movement of robot avatar in the virtual environment and see the result before operate the remote robot. Because the operation orders that sent to the remote controller of robot are checked and validated, this kind of control can guarantee that the system is trustiness.This dissertation chooses the Browser/Server structure models as the design and implementation of remotely controlled robot system based on Web, and uses the XML as the standard in order to resolve the data exchange format for remote data transmission between different software platforms.This dissertation provides a prototype system. The prototype system indicates that the robot avatar used in the robot teleoperator can resolve the problems about real-time in simulation and reliability of the web-based tele-operation system. Further study about the robot avatar will be discussed in this dissertation.