Research On Virtual Hand Interaction Technology For Space Missions

Space test and launch mission is a high-risk and high-investment complicated system engineering.It requires relatively high operational capacity for the site operators in the testing process.As a means of communication and information transmission,virtual reality technology can provide a virtual environment for the space test and launch mission.And the operator can drive the virtual hand in the virtual environment to complete the test task in order to improve operational efficiency.Regarding space test and launch mission as the researching background,this paper mainly discussed the hand tracking technology based on MEMS inertial sensor and realized the design of gesture recognition and semantic interaction.To realize the virtual hand motion tracking,a motion tracking system based on inertial sensor was developed.And the three-dimensional hand skeleton model was constructed by analyzing the skeletal structure and motion characteristics of human hands.By calibrating the initial gesture of a hand,the sensor coordinate system was transformed to the hand skeleton coordinate system.Furthermore,a method of estimating the hand skeleton ratio was put forward which made the virtual hand more realistic.In this way,the virtual hand position based on kinematics was calculated to accomplish the hand movement real-time tracking.Last but not least,the designed typical hand gesture has been collected and represented by extracting behavioral features.The data dimensions of hand gesture can finally be reduced by using principal component analysis(PCA).And the classification algorithm based on grid search and 5-fold cross validation and supports vector machine was adopted.For the classification algorithm,polynomial kernel function,radial basis kernel function and combined kernel function were respectively used to compare the recognition rate,and the optimal kernel function was selected to realize the gesture recognition.In order to complete the interactive research in the space test and launch mission,the Hidden Markov Model was used to identify the sequence of hand movement.After that,the semantic interactive process of the virtual hand was designed oriented to a specific scene and verified in this process.The research results of the paper have an excellent performance in the simulation environment of space launch mission.