Single motor driven soft actuator design based on nonuniform sheering auxetic structure

Grasping functionality is one of the core functionalities that a manipulator needs to possess. Traditional rigid manipulators are typically composed of rigid materials. However, when dealing with objects of complex shapes, irregular surfaces, or soft materials, rigid manipulators often face challenges in effectively grasping and stably holding objects due to their rigidity, which can lead to damage or failure. To address these issues, constructing manipulators using soft actuators can be highly advantageous. In most current research, soft actuators are typically composed of flexible materials and fluids, which can result in highly complex dynamic behaviors and nonlinear characteristics. This complexity makes precise modeling and control of soft actuators more challenging, necessitating the use of advanced control algorithms and techniques to mitigate nonlinear effects. In this study, we first establish a mathematical model for the torsional and bending deformations of non-uniform shearing-auxetic structures. Subsequently, we validate the reliability of the mathematical model through simulation. Finally, we design a soft actuator that requires only single-motor control, which is based on the structural design of non-uniform shearing-auxetic structures. This type of soft actuator not only simplifies control aspects but also facilitates practical modeling and manufacturing processes. Moreover, it is capable of achieving spiral grasping functionality.