Research On Task Simulation Of Space Station Manipulator Based On Virtual Reality

With the development of space robot technology,the space manipulators have been able to assist or supersede the astronauts to accomplish some precise,complicated,and dangerous tasks,which relieve the risk of extravehicular activities and the pressure of space work,thus enhance the efficiency of space exploration.However,due to the increasing complexity of the tasks of space manipulators,ground experiments are far from enough to test the tasks of them.Therefore,it becomes a promising application to study the safe,convenient,and low-cost manipulator simulation and realize the task simulation of the space manipulators in the virtual environment.According to requirements of the space manipulators in our country,a space station manipulator simulation software is developed,which realizes the 3D visualization and the task simulation.It focuses on the reconfigurable virtual modeling method and the collision detection of the space station manipulators and executes the simulation of a typical task.The research content is mainly divided into the following parts:Firstly,a space station manipulator simulation software based on virtual reality is developed.Based on the analysis of the kinematics of the manipulator,a 3D virtual environment and a human interactive interface are built,which realize the kinematics simulation and give operators a realistic vision telepresence.Also,the simulation of the preprogrammed trajectory,teleoperation,and parameter control are implemented.Secondly,a reconfigurable virtual modeling method is studied to adapt the model to complicated task simulation in unknown and variable environment,which possesses high flexibility.A reconfigurable virtual modeling method based on vector,a C++ container is proposed,which implements the model reconfiguration with addition,removal,and transformation and meets the requirements of model reconfiguration before and during the simulation.Thirdly,the collision detection of the space station manipulator is studied,which realizes the fast collision detection of the manipulators and the environment.Based on the Flexible Collision Library,a boundary volume-based collision detection method is carried out through an optimized strategy,which involves excluding the pairs that are impossible to collide.Finally,a typical manipulator task simulation,the pallet transportation is completed to test the reconfigurable virtual modeling method and the collision detection method.Based on the analysis of the requirement of the pallet transportation,path points of the manipulator endpoint are selected and the path planning is executed.Then the task simulation is implemented with the reconfigurable virtual modeling method and the collision detection method,which verifies the effectiveness of the methods.