A Modular Shape-Adaptive Mechanism for Robust Robotic Grasping

Underactuated and adaptive robotic hands are known for their ability to achieve multiple contact points on arbitrarily shaped objects with relatively simple actuation, improving grasp stability. However, in some cases the sequence in which these contact points are initiated does not promote robust capture of the grasped object. This paper presents the design of a new type of underactuated grasper based on an asymmetric pantograph structure. The new grasper achieves robust enveloping capture of arbitrarily shaped objects (including non-convex shapes) while maintaining balanced forces at multiple contact points. The design is easily adjustable for differently sized objects.