Investigation Of 3D Printing-based Bionic Soft Actuators And Their Performances

Compared with traditional rigid robots,soft robots have the advantages of strong adaptability,high interactivity and high safety.The flexibility of soft robots provides a new way to solve the problems faced by traditional instruments such as robots,drives,and grippers.Soft robots can use the highly nonlinear response to actuation to complete complex motions and achieve tasks that are difficult to accomplish with traditional rigid instruments.First,inspired by the movement of octopus tentacles in nature,this paper proposes a 3D printing-based six-claw actuator with an embedded pneumatic mesh drive unit,which is composed of a pullable top layer and a non-stretchable bottom layer..In order to ensure the good driving performance of the driver,the structural design of the pneumatic grid inside the driving unit is very important.In this paper,the influence of key structural parameters of aerodynamic meshes on the driving performance of the drive unit,including the mesh height,mesh width and mesh number,is discussed,and the drive pressure threshold of the drive unit under different structural parameters is discussed,and the drive performance test is clarified.The external air source pressure required in the calculation;analyze the relationship between the driving speed and the driving force and the driving air pressure of the pneumatic driving unit under the conditions of different grid heights,grid widths and grid numbers,and use the hyperelasticity theory Mooney-Rivlin The nonlinear material model is used to analyze the large deformation process of the pneumatic drive unit,and the good grasping performance and durability of the drive are verified through the physical grasping test and repeated driving test.Secondly,inspired by the motion of the elephant trunk,a bionic drive arm with multi-directional bending capability is proposed.The interior of the drive arm is composed of three embedded pneumatic drive units and an embedded module for increasing the rigidity of the drive arm.The driving principle of the driving arm is expounded,and the driving pressure threshold of the driving arm under the specific structure is analyzed and the driving pressure is determined.The effects of different aspect ratios on the curvature radius,bending angle and tip offset of the drive arm under specific air pressure were studied.The relationship between the offset of the tip of the driving arm and the driving time is obtained by linear fitting,and a mathematical model of bending motion is established.This motion model is used to predict the bending direction of the driving arm by adjusting the driving time of each driving unit,and it is verified by experiments..In order to realize the separate control of the three drive units of the drive arm,a programmable pneumatic drive system was designed and developed,and the drive time of each drive unit was independently controllable.The stability of the driving performance of the driver is verified by repeated bending tests,and the deformation process of the driving arm is analyzed with the finite element analysis software.Finally,the potential applications of the driver in the fields of electromagnetic shielding and flexible sensing are demonstrated,and the feasibility of its application is verified by experiments.The signal shielding effects of drivers with different underlying composite materials were compared,and the effects of underlying materials with different copper powder contents on the electromagnetic shielding effects of drivers were explored.Use the conductive materials of multi-walled carbon nanotubes and graphene oxide to make flexible sensors,compare the conductive properties of the sensors under different spraying times and concentrations of conductive materials,measure the resistance changes of the sensors under different tensile strains,and verify through repeated tests.the stability of the sensor.The sensor is compounded on the surface of the flexible actuator,and the motion state of the actuator is monitored in real time through its pull-resistance characteristics.In this paper,the influence of the structural parameters of the embedded drive unit grid of the drive on the performance of the drive is analyzed,and its structural parameters are optimized to achieve the characteristics of high adaptability,high wrapping,low driving pressure,and large deformation.The development of the six-claw actuator;the linear and nonlinear relationship between the motion parameters of the driving arm and the time was studied,and the fabrication and control method of the multi-directional bending bionic driving arm was proposed;the electromagnetic shielding of the actuator and the driving sensing direction were carried out The exploration of potential applications has verified the theoretical and experimental feasibility of the 3D printed flexible drive system,and provided experimental and theoretical basis for the application of 3D printed flexible drives in key fields such as flexible robotics,aerospace,medical care,and military.