Functioning of Intelligence and Dexterity in Multi-Fingered Hands by Sensory-Motor Coordination

首先考虑滚动接触约束，以一种显式的方式建立了基于手指-拇指对立的捏击模型。本课题在假定手指端为半球形刚性的情况下，分析了动态意义上的捏捏运动的稳定性。本项目最值得关注的成果必须总结如下：1)机器人的一对手指即使闭上眼睛也能像人类一样抓取物体，实现“盲抓”；2)通过引入“灵巧度指数”，针对拇指和食指不同关节之间的角色分担，实现“灵巧度分析”。该项目的最终目标是通过两个或多个具有多个关节的手指在三维空间中运动来实现三维稳定抓取。在不考虑三维空间滚动接触的非完整约束的情况下，可以推导出具有非完整约束的整个指-物系统模型。然后，从理论上证明，当物体有两个平行的平面时，存在一个手指-拇指逆力信号，实现动态意义上的稳定捏紧。完成了3个自由度的三维手指的设计，并制作或收集了所有必需的机械部件。只剩下利用这对三维机器人手指进行三维稳定抓取实验。

Pinching based on the finger-thumb opposition was first modeled in an explicity way by taking into account rolling contact constraints. Under this research project, stability of pinching motions in a dynamic sense is analyzed under the assumption that finger-ends are of hemispherical shape but rigid. The most noteworthy outcomes under this project must be summarized in the followings : 1) "Blind grasping" can function even in the case of a pair of robot fingers likely as human grasp on object even if they close eyes and 2) "Dexterity Analysis" can be done through introducing "dexterity index" and aiming at role-sharing among different joints of thumb and index finger.The final goal of the project is to realize 3-Dimensional stable grasping by means of two or more fingers with multiple joints moving in 3-Dimensional space. Regardless of the non-holonomic constraint of rolling contacts in 3-D space, a whole fingers-object system model with non-holonomic constraints could be derived in a rigorous way. Then, it is shown theoretically that there exists a signal of fingers-thumb opposition force that realizes the stable pinching in a dynamic sense, provided that the object has two parallel flat surfaces.Design of a 3-Dimensional finger with 3 DOFs has been finished and all necessary mechanical parts are made or collected now. Only it remains to carry out the experiment of 3-D stable grasping by using this pair of 3-D robot fingers.