Mechanical Characteristic Research And Application Of The Twisted And Coiled Actuator

Artificial muscle is a flexible actuator that can produce action output similar to the length contraction and recovery of biological muscles.It has a wide application prospect in the fields of continuum robots,bionic robots,and wearable devices.Twisted and coiled actuator(TCA)made of polymer fiber such as nylon is a spiral coil-like new artificial muscle based on twisting and coiling nylon(polymer)fiber.It has advantage of low hysteresis effect,long cycle life,low material and production cost,and energy density.High output and large deformation,and has broad application prospects in the field of flexible drive.In this paper,TCA is taken as the research object.Making method and manufacturing process of different types and driving forms of TCA are summarized;A multi-functional TCA manufacturing platform is introduced,which can make TCA quickly,easily and repeatedly;The parameters of manufacturing and the geometry parameters of TCA are measured and analyzed.The geometric model of the TCA explains the geometric changes that occur when the TCA is made from the straight precursor line into the spiral coil type;From the perspective of the anisotropy of deformation of polymer materials during heating,the principle of driving artificial muscles is explained;Using the Dummy-load method,macroscopic static model of TCA due to the temperature change is established.Static model of TCA is established,the air heating method is selected as the heating method for TCA mechanical performance experiments;A measuring platform that can measure the mechanical properties of TCA is designed,and multiple sets of experiments is performed.Parameters of static model is obtained so that the artificial muscle can be quantitatively analyzed in application.For the application of the cable-driven joint robot module,the forward process of geometric design and static analysis of the joint when TCA is applied as the linear actuator is given.TCA is applied to the symmetrical modular joint of the 3D printing as a linear actuator,and experimental values of the deflection angle are compared with the theoretical values by heating TCA to pull the joint to different deflection angle under the load.It lays a theoretical and practical foundation for the application of artificial muscles as linear actuators in mechanical structures.