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Developing a dexterous robotic hand that mimics natural human hand movements is challenging due to complicated hand anatomy. Such a practical design should address several requirements, which are often conflicting and force the designer to prioritize the main design characteristics for a given application. Therefore, in the existing designs the requirements are only partially satisfied, leading to complicated and bulky solutions. To address this gap, a novel single-actuated, cable-driven, and self-contained robotic hand is presented in this work. This five-fingered robotic hand supports 19 degrees of freedom (DOFs) and can perform a wide range of precision and power grasps. The external structure of fingers and the thumb is inspired by Pisa/IIT SoftHand, while major modifications are implemented to significantly decrease the number of parts and the effect of friction. The cable configuration is inspired by the tendon structure of the hand anatomy. Furthermore, a novel power transmission system is presented in this work. This mechanism addresses compactness and underactuation, while ensuring proper force distribution through the fingers and the thumb. Moreover, this power transmission system can achieve adaptive grasps of objects with unknown geometries, which significantly simplifies the sensory and control systems. A 3D-printed prototype of the proposed design is fabricated and its base functionality is evaluated through simulations and experiments.
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STAR–2: A Soft Twisted-string-actuated Anthropomorphic Robotic Gripper: Design, Fabrication, and Preliminary Testing
While numerous studies have been conducted, developing a compliant robotic gripper capable of replicating human hand grasping and manipulation capabilities is still challenging. This paper presents the design, fabrication, and preliminary testing of an anthropomorphic soft robotic gripper driven by twisted string actuators (TSAs). Termed as STAR–2, it is a second generation TSA-driven soft gripper from the Smart Robotics Laboratory at the University of Nevada, Reno. The novel design facilitated a monolithic structure comprising of a 3-degrees-of-freedom (DOF) thumb and four fingers each with 2-DOFs. On account of using tendon-based actuation and the large footprint required for the thumb, the design employed meticulously planned tendon routing within the monolithic structure. Preliminary results showed STAR–2’s enhanced ability to demonstrate grasp taxonomies and dexterity over STAR–1.
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- Award ID(s):
- 1852578
- PAR ID:
- 10535466
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 978-1-6654-7633-1
- Page Range / eLocation ID:
- 643 to 648
- Format(s):
- Medium: X
- Location:
- Seattle, WA, USA
- 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/AIM46323.2023.10196149
