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arXiv · 2203.07456

Designing Underactuated Graspers with Dynamically Variable Geometry Using Potential Energy Map Based Analysis

C. L. Yako·Shenli Yuan·J. Kenneth Salisbury
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Abstract

This paper introduces an extension to the energy map method for in-hand manipulation. Energy maps are used to predict how a part will evolve in the grasp given a specific actuation input to the gripper. Previous approaches assumed frictionless contacts, but we show analytically that friction can be included in the energy maps when using two-link underactuated fingers by understanding the evolution of the part-finger contact. These friction-based energy maps were used to evaluate the importance of various tendon-pulley gripper parameters across nearly 6 million simulated grasping scenarios. Specifically, a variable palm width is needed to manipulate parts of varying scales, and a variable transmission ratio, or the ratio of the distal to the proximal pulley radii, is needed to draw parts into a cage or to maintain a tip prehension grasp.

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C. L. Yako, Shenli Yuan, J. Kenneth Salisbury. 2022-03-14. Designing Underactuated Graspers with Dynamically Variable Geometry Using Potential Energy Map Based Analysis. https://doi.org/10.25740/mm182vq8220%2010.1109%2Firos47612.2022.9982148

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