Preparation And Research Of Novel Soft Actuators Based On Cellulose Nanofibers

Traditional robots are composed of rigid components,and their disadvantages are heavy weight,poor adaptability,and high noise.In contrast,soft robots mimic the way living things move,using smart materials to deform,bend,expand and contract to control robot motion.They have the characteristics of light weight,high flexibility,and strong adaptability.In software robotics technology,the study of actuators is crucial.At present,ionic electroactive polymers,as a kind of flexible actuators,have received extensive attention due to their advantages such as low driving voltage,high efficiency,and large strain.Ionic electroactive polymer is a material that can generate deformation under the action of an external electric field or generate an electrical signal under the action of an external force.It has the dual functions of a sensor and a driver.It has broad application prospects.In this paper,a new type of ionic electroactive polymer was prepared based on functionalized cellulose nanofibers and ionic liquids,and its actuation-sensing properties and applications were explored.The specific content is as follows:First of all,the high conductivity polymer PEDOT:PSS is used as the electrode of the actuator,which solves the problem that the traditional IPMC cannot work in the air for a long time and the electrode is easy to fall off;doping graphene into the cellulose nanofiber ion exchange membrane,Increased the migration speed of ions in the membrane.The structure and properties of the material were verified by scanning electron microscopy,infrared spectroscopy,XRD and other analysis.Secondly,the driving mechanism of the cellulose nanofiber actuator was explored,a test platform for driving characteristics was built,and the bending changes of the actuator under different voltages and different frequency driving signals were studied,and compared with other researchers’ actuators.The results show that the actuators prepared in this paper have high bending displacement and stability.Based on the driving characteristics,applications such as bionic electronic flowers,bionic fingers interacting with electronic screens,and spiral brackets were designed.Then,the sensing mechanism of the cellulose nanofiber actuator was explored,and a test platform for sensing characteristics was built to study the static sensing characteristics and dynamic sensing characteristics of the actuator,as well as the relationship between perception and the bending change of the actuator.Based on the perceptual characteristics,a micro force sensor is designed,and its theoretical model and experimental model are established.The results show that the micro force sensor has high sensitivity and linearity.Finally,according to the driving characteristics and sensing characteristics of the cellulose nanofiber actuator,a driving/sensing integrated gripper system is designed to clamp and fix some tiny objects.The gripper can sense the magnitude of the applied force and adjust its strength adaptively,so as to achieve precise and flexible clamping of fixed objects.The gripper has a wide range of potential application scenarios,such as medical,industrial,agricultural and other fields.