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ABSTRACT As modern agriculture faces increasing demands for efficiency and automation, this study presents a novel, untethered soft gripper system designed for autonomous and efficient harvesting. At the core of this innovation is a piston‐driven, pneumatically actuated gripper embedded with flexible tactile sensors, enabling operation without an external air source. The system integrates a compact motorized syringe, forming a closed‐loop fluid circuit that provides precise pressure control for adaptive grasping. The pneumatic actuation mechanism regulates air pressure from −30 to 180 kPa, allowing the gripper to perform delicate and adaptive handling, particularly suited for tree fruits and other fragile crops. A key feature of the system is its intelligent control mechanism, which seamlessly combines pneumatic and electrical systems to enhance autonomy and versatility in agricultural applications. The integration of size recognition and adaptive grasping, enabled by force feedback from embedded tactile sensors, ensures safe, efficient, and damage‐free harvesting. Demonstrating exceptional potential for autonomous agricultural operations, the untethered soft gripper system offers enhanced independence, maneuverability, and adaptability across diverse harvesting environments. Its ability to optimize crop handling while minimizing damage highlights its significance as a pioneering solution for the future of automated agriculture.
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Soft, All‐Polymer Optoelectronic Tactile Sensor for Stick‐Slip Detection
Abstract The mechanoreceptors of the human tactile sensory system contribute to natural grasping manipulations in everyday life. However, in the case of robot systems, attempts to emulate humans’ dexterity are still limited by tactile sensory feedback. In this work, a soft optical lightguide is applied as an afferent nerve fiber in a tactile sensory system. A skin‐like soft silicone material is combined with a bristle friction model, which is capable of fast and easy fabrication. Due to this novel design, the soft sensor can provide not only normal force (up to 5 Newtons) but also lateral force information generated by stick‐slip processes. Through a static force test and slip motion test, its ability to measure normal forces and to detect stick‐slip events is demonstrated. Finally, using a robotic gripper, real‐time control applications are investigated where the sensor helps the gripper apply sufficient force to grasp objects without slipping.
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- Award ID(s):
- 1849213
- PAR ID:
- 10386053
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 7
- Issue:
- 12
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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