Research On Simultaneous Location And Map Building Of Mobile Robot For Virtual Reality And Teleoperation

With the rapid development of the robot, computer and space navigation technology and syncretization between them these years, the robot is applied more and more widely in the exploration of the unknown environment. To explore the unknown environment, the robot should have the ability of self-navigation, self-electronic map production and transmission. Furthermore, to complete some special assignment, the robot should be under the teleoperation. In decade years, there has been much harvest in the field of robot self-electronic map production and teleoperation throughout the world. While the self-electronic map production and teleoperation are separated in these results, that is, the map only can been displayed, and the teleoperation mostly need been carried out by the remote video. Then the problem appears that the operator doesn't know the position of the robot when telecontrols it, so it is difficult to get a whole plan of the robot movement.Supported by Hi-tech Research and Development Program of China (No. 2003AA421040), the author has done deep research on the above problem in this essay. It established a mobile robot simultaneous localization and map building system to virtual reality and teleoperation, which can build 3D model and display the solid graphics, and control the robot by the wireless LAN with virtual reality system. In the meantime, the system make the operator feel in the real environment based on the character of the virtual reality.Exploring the environment by ultrasonic sensors, the essay researched the HEBUT-II mobile robot, and stated three points as follows: the simultaneous localization of the robot and the autonomously builded 3D map, from the 3D map to establishing the virtual reality system, teleoperation of the robot based on the virtual reality system.The essay's content as follows:1. Set up the localization method of the robot by the GPS and milemeter, built the movement control model of the robot bodywork through analyzing the robot wheel structure. Established the measure model of ultrasonic sensors according to the ultrasonic sensors position and the crosstalk problem of the HEBUT-II robot. Established the kinematics model of 5DOF manipulator by D-H method, then analyzed joint velocity of the manipulator and Jacobian matrix. Designed the control system of the manipulator.2. Put forward the scheme of building 3D electronic map by the robot independently with ultrasonic sensors, lucubrated the FastSLAM algorithm, ensured the error ellipse of landmark position by particle filter and extended Kalman filter, and based on which, got the planar profile of the environment by merging the error filters center points to curve by adaptive fuzzy clustering algorithm integrated with noise clustering technique. Measured the landmark height by the sonar on manipulator end- effector after establish 2D model. Obtained the 3D model by connecting the scale of the landmark height with the planar model.3. Building the 3D electronic map with stereo display and teleoperation, whose vision interface was virtual reality system. The map's geometry model was from the 3D model. Made the electronic map being provided with stereo display ability through researching on stereo display algorithm and applying it. Realized the scene emersion function with immersion by connecting stereo display facilities. Strengthened the safety by the OBB (Oriented Bounding Boxes) collision detection. Used the data gloves as the interaction machine of the person and the robot, also designed gesture aggregate for robot teleoperation. The virtual robot in the map and the real robot moved simultaneously, which the whole process was natural and direct according with the expression ways of the human in the environment.4. Established two separated telecommunication systems based on WLAN and GRPS, which transmit the message of map model, teleoperation order and long-distance video. As the main transmit method, WLAN connected by BSS topology structure. Extended the communication distance by using high gain antenna. Improved the transmit speed by studying and designing the multithread transmit way according to high bandwidth requirement of video transmit. As the assistant way of GPRS, telecontrolled the robot by AT order, or set up the map and teleoperated by startuping the programming in the robot computer.5. In the essay, experiments about the HEBUT-II robot autonomously building the map had been done on the playground, office and aisle. In these experiments, the robot could establish the 3D model which has higher precision in time basically, and the map can bring the immersion to the operator.