三指力封闭抓取的内力存在性研究

On Internal Force Existence of Three-fingered Hand Force-closure Grasping

针对指端与物体构成有摩擦固定点接触的情况,基于内力的特性分析,对三指力封闭抓取时的内力存在性进行研究,推导了摩擦扇存在条件和三指内力汇交条件。通过内力汇交多边形的构成特点分析,提出了根据摩擦扇边界线交点相互位置关系研究汇交多边形存在性的完整方法。在考虑内力平衡关系的基础上,给出了基于数学计算的内力存在性通用判别算法,并结合实例说明了方法的有效性。

Under the condition of fix-point contacts with friction between the three fingertips and the object, the existence of internal forces was investigated based on the characteristic analysis of internal forces. The existence condition of frictional sectors and the concurrent condition of three internal forces were established. An integrity method was put forward, by which the existence of concurrent polygon can be determined according to the relative locations between the frictional sectors and their borderline intersections. By taking into account the requirements of internal forces equilibrium, a general algorithm for judging the existence of internal forces is founded. An example was given to illustrate the validity of the algorithm.