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Manipulation tasks often require a high degree of dexterity, typically necessitating grippers with multiple degrees of freedom (DOF). While a robotic hand equipped with multiple fingers can execute precise and intricate manipulation tasks, the inherent redundancy stemming from its high‐DOF often adds complexity that may not be required. In this paper, we introduce the design of a tactile sensor‐equipped gripper with two fingers and five‐DOF. We present a novel design integrating a GelSight tactile sensor, enhancing sensing capabilities and enabling finer control during specific manipulation tasks. To evaluate the gripper's performance, we conduct experiments involving three challenging tasks: 1) retrieving, singularizing, and classification of various objects buried within granular media, 2) executing scooping manipulations of a 3D‐printed credit card in confined environments to achieve precise insertion, and 3) sensing entangled cable states with only tactile perception and executing manipulations to achieve two‐cable untangling. Our results demonstrate the versatility of the proposed gripper across these tasks, with a high success rate of 84% for singulation task, a 100% success rate for scooping and inserting credit cards, and successful cable untangling. Videos are available athttps://yuhochau.github.io/5_dof_gripper/.
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Benchmarking Planar Rotation Capabilities of Robot Hands with Fingers
Rotation manipulation tasks are a fundamental component of manipulation, however few benchmarks directly measure the limits of a hand's ability to rotate objects. This paper presents two benchmarks for quantitatively measuring the rotation manipulation capabilities of two-fingered hands. These benchmarks exists to augment the Asterisk Test to consider rotation manipulation ability. We propose two benchmarks: the first assesses a hand's limits to rotate objects clockwise and counterclockwise with minimal translation, and the second assesses how rotation manipulation impacts a hand's in-hand translation performance. We demonstrate the utility of these rotation benchmarks using three generic robot hand designs: 1) an asymmetrical two-linked versus one-linked gripper (2v1), 2) a symmetrical two-linked gripper (2v2), and 3) a symmetrical three-linked gripper (3v3). We conclude with a brief comparison between the hand designs and a observations about contact point selection for manipulation tasks, informed from our benchmark results.
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- PAR ID:
- 10451866
- Date Published:
- Journal Name:
- Benchmarking Planar Rotation Capabilities of Robot Hands with Fingers
- Page Range / eLocation ID:
- 559 to 565
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/UR57808.2023.10202227
