Simulation and Design of Two-Degree-of-Freedom Underactuated Mechanical Fingers

Abstract The design of underactuated mechanical fingers is addressed in this article. The objective of the research is to design a robust mechanical hand capable of performing industrial tasks involving the grasping of a wide variety of objects with large forces. To this end, the taxonomy of the grasps is first reviewed. Then, the principle of underactuation — which leads to shape adaptation of the hands — is introduced and a review of the existing underactuated mechanical hands is provided. Architectures of two-degree-of-freedom underactuated fingers are then proposed and a simulation tool is designed to analyze their behavior. It is shown that underactuation is a very promising avenue when only grasping is required (no manipulation). Simulation results are given and discussed in order to illustrate the usefulness of the simulator and general design guidelines are proposed. Finally, a design of an underactuated finger is presented as an example. The design presented here demonstrates that the use of underactuation can lead to versatile grasping capabilities with reduced complexity.