Enabling Grasp Action: Generalized Evaluation of Grasp Stability via Contact Stiffness from Contact Mechanics Insight
This work addresses grasp stability evaluation for robotic grippers, presenting an incremental improvement by applying contact mechanics insights to a known bottleneck in robotic manipulation.
The paper tackles the problem of evaluating robotic grasp stability by proposing a new measurement approach based on contact mechanics theory, constructing a grasp stiffness matrix with normal, tangential, and torsion coefficients. The result shows that their method, validated through two grasping cases, produces similar stability trends to a standard grasping index, confirming its effectiveness.
Performing a grasp is a pivotal capability for a robotic gripper. We propose a new evaluation approach of grasping stability via constructing a model of grasping stiffness based on the theory of contact mechanics. First, the mathematical models are built to explore soft contact and the general grasp stiffness between a finger and an object. Next, the grasping stiffness matrix is constructed to reflect the normal, tangential and torsion stiffness coefficients. Finally, we design two grasping cases to verify the proposed measurement criterion of grasping stability by comparing different grasping configurations. Specifically, a standard grasping index is used and compared with the minimum eigenvalue index of the constructed grasping stiffness we built. The comparison result reveals a similar tendency between them for measuring the grasping stability and thus, validates the proposed approach.