虚拟装配中基于生理约束的虚拟手建模与抓持规划

Hand modeling and motion controlling based on lay figure in virtual assembly

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。

Virtual hand is important for the operator to interact with the object in virtual environment. To control the grasp motion of virtual hand exactly and improve the authenticity sense in virtual assembly simulation, a new virtual hand model with reductive 3-joint-shaft hierarchical structure was constructed based on the analysis of human hand anatomical structure and physiological motion restriction. Then a prototype of the virtual hand was developed by using 3-D virtual reality software EON. Each finger was simplified as links with 3 degree of freedoms. With the computation of the finger joint angles under goal state with inverse kinematics method and the use of joint interpolation and iteration, all joints in hand joint chains were controlled. Finally, the simulation demonstrated the effectiveness and feasibility of the proposed method.