The design and implementation of virtual hand grasp behavior process in virtual assembly

Virtual hand is an important medium for implementation of human-computer interaction in the process of virtual assembly. And the comparability between the action of virtual hand and real man-hand has always been regarded as one of the important criteria to judge whether the virtual environment has the property of immersion. On the basis of analyzing the relative position,posture,and motion behavior relationship between virtual hand and the object to be operated during virtual assembly,this paper proposed an implementation method of combining grasp index with collision detecting technology for identifying grasp action of virtual hand. The method is to identify grasp/quit using grasp index and to implement joint angle adjustment through simulation cyclic iteration and joint angle interpolation calculation. Although some traditional method identifying the grasp action on the basis of the shape of the object is operated,the simulation result getting from virtual environment created by EON STUDIO shows that it has good features of serviceability and fidelity to realize operation control of virtual hand.     

虚拟装配中基于生理约束的虚拟手建模与抓持规划

为控制虚拟手准确合理地完成虚拟零件的抓握动作,以方便快捷地实现虚拟装配仿真,在深入分析人手的解剖结构和关节运动生理约束的基础上,提出利用层次结构并借助三维虚拟现实软件EON,建立虚拟手几何模型和实现抓持控制的方法.该方法将手指简化为三关节连杆结构,采用逆向运动学方法,针对待拾取零件的位置计算出在目标位姿下各运动关节的角度值.进而利用关节插值方法,以迭代的方式实现对手部关节链上各个关节的运动控制,仿真结果验证了上述方法的可行性与实时性.