Virtual prototype model for lunar rover missions

By means of virtual prototype technolgy, the virtual enviroment of the lunar rover is established on graphics workstation. The model of virtual lunar rover based on rocker and redirector is derived for full six degree of freedom motions enabling movements in three directions, as well as pith, roll and yaw rotations. In order to make the operator see and believe the virtual enviroment of the scene while controlling the rover, a self-calibration system is developed by the method of transforming 3-D CAD models into 2-D graphics and superimposing the model built on the computer onto the image taken by the CCD camera, which can calibrate the figure of virtual enviroment. For the purpose of dispelling the time delay impact on the stability of the teleoperation system during lunar missions, a two-level control frame of teleoperation based on virtual reality preview, which can lay communication time delay out of the control loops, is applied to the simulation system. A man-machine interface based on six degree Space ball is developed so as to control the virtual lunar rover efficiently. The effectiveness and the feasibility of the model are verified by the climb simulation experiments of the virtual lunar rover.