A soft gripper approach with optimized monolithic actuator and sensor strategies for agricultural applications

The rapid global population growth poses significant social and agricultural challenges. With projections exceeding 10 billion by 2059, doubling agricultural output becomes crucial. Traditional methods of increasing production face sustainability, efficiency, and environmental limitations due to climate change. Thus, developing soft robotic solutions for agriculture is essential, placing the soft gripper at the forefront of agricultural innovation. This thesis tackles the intricate task of creating a sensorized soft gripper specifically for agricultural use. The aim is to develop gripper systems capable of autonomous operation, particularly vital for delicate tasks such as fruit handling, without dependence on visual feedback. To achieve this, the research involves several interconnected aspects. It begins by designing and fabricating soft pneumatic actuators engineered for gentle interaction with objects, versatile across various targets. These actuators prioritize enhanced reliability to prevent mechanical failure and ensure seamless grasping operations in agricultural environments. Furthermore, the thesis integrates these actuators into a unified grasping platform engineered for stability and adaptability across diverse agricultural targets. This integration is vital for deploying the gripper system effectively across various tasks and environments, spanning from fields to warehouses. A crucial research element involves developing and integrating a dedicated sensory strategy for assessing fruit ripeness. This strategy empowers the gripper to evaluate fruit ripeness through tactile feedback, aiding informed decision-making during handling operations. Additionally, the study explores diverse soft-sensing strategies, different transduction mechanisms, and fabrication techniques to enhance sensing performance, focusing on magnetic and optoelectronic transduction. Inspired by nature's tactile sensing mechanisms, the research aims to develop a morphing tactile sensor, transitioning it from a passive transducer to an active element for real-time tuning. To complement these efforts, the thesis explores different signal conditioning and processing methodologies to characterize the proposed sensing strategy. This meticulous calibration and refinement process ensures precise and reliable tactile feedback, a fundamental step toward using soft grippers in agriculture.