Study on the Mapping Relationship Between Objects’ Contour and Finger Dimension of the Self-Adaptive Grasper

Self-adaptive graspers are employed in a wide range of applications. In this article, we study the number of knuckles and the dimension analysis theory of robot graspers from the object contour based on the grasper’s adaptive performance. Our goal is to develop a robotic grasper dimension design software that can derive the optimal dimensions and number of knuckles for grasping an object based on known object contours. First, the grasped irregular object contour configuration is analyzed, and the mapping analytical model between the finger knuckle link length and the object contour is established. Second, the average Euclidean distance method is introduced to establish the evaluation index of the self-adaptive performance of the grasper to the object, and the relationship between the self-adaptive and knuckle length is analyzed to determine knuckle link length through this index. Then, based on the discretization method, the mathematical relationship between the grasper multistage transmission ratio and transmission mechanism link length is established. The influence of transmission ratio and self-adaptive performance evaluation indexes is a weighted analysis to determine the final grasper knuckle number. Finally, we develop a self-adaptive grasper dimension design software and validate the theoretical analysis with examples and physical experiments. The work presented in this article provides a reference for the analysis of the number and dimensions of self-adaptive grasper knuckles.