Fuzzy Logic Control for Grasping 3D Objects with Sliding Contacts

The overwhelming complexity of the grasping process and imprecise knowledge about articulated robot hand systems leads to a certain control problem. In order to solve these problems, the paper proposes a new design of fuzzy control approach for two fingered robot hand, which is able to control simultaneously grasping and slipping of 3D fragile objects in unstructured environment. In this context, the unstructured environment means that we consider objects of different mass and shape whose physical properties such as mass, rigidity and friction are unknown. The control scheme consists of a combination of two fuzzy logic controllers. The first controller is used for insuring object stable grasping and the second for controlling object slipping motion. Hence, by adding the slippage information, we achieved a grasping task with minimum fingertip force which reduces the risk of deforming or crushing the gripped object. The proposed control architecture allows a safe and stable grasping without needing to measure the fingertip force, so the noise introduced by the force sensors does not exist. Several simulation results are presented to demonstrate the effectiveness of the developed work. Keywords— Robot grasping, Slip control, 3D unknown object, fuzzy logic control.