Conventional liquid crystal elastomer(LCE)-based robots are limited by the need for complex controllers and bulky power supplies,restricting their use in microrobots and soft robots.This paper introduces a novel light...Conventional liquid crystal elastomer(LCE)-based robots are limited by the need for complex controllers and bulky power supplies,restricting their use in microrobots and soft robots.This paper introduces a novel light-powered dicycle that uses an LCE rod,enabling self-rolling by harvesting energy from the environment.The LCE rod serves as the driving force,with energy being supplied by a line light source.Employing a dynamic LCE model,we calculate the transverse curvature of the LCE rod after deformation,as well as the driving moment generated by the shift in a rod’s center of gravity,which allows the dicycle to roll on its own.Through extensive numerical simulations,we identify the correlations between the angular velocity of the dicycle and the key system parameters,specifically the light intensity,LCE rod length,light penetration depth,overall mass of the dicycle,rolling friction coefficient,and wheel radius.Further,the experimental verification is the same as the theoretical result.This proposed light-powered self-rolling dicycle comes with the benefits of the simple structure,the convenient control,the stationary light source,and the small luminous area of the light source.It not only demonstrates self-sustaining oscillations based on active materials,but also highlights the great potential of light-responsive LCE rods in applications such as robotics,aerospace,healthcare,and automation.展开更多
Self-vibrating systems comprised of active materials have great potential for application in the fields of energy harvesting,actuation,bionic instrumentation,and autonomous robotics.However,it is challenging to obtain...Self-vibrating systems comprised of active materials have great potential for application in the fields of energy harvesting,actuation,bionic instrumentation,and autonomous robotics.However,it is challenging to obtain analytical solutions describing these systems,which hinders analysis and design.In this work,we propose a self-vibrating liquid crystal elastomer(LCE)fiber-spring system exposed to spatially-constant gradient light,and determine analytical solutions for its amplitude and period.First,using a dynamic model of LCE,we obtain the equations governing the self-vibration.Then,we analyze two different motion states and elucidate the mechanism of self-vibration.Subsequently,we derive analytical solutions for the amplitude and frequency using the multi-scale method,and compare the solutions with numerical results.The analytical outcomes are shown to be consistent with the numerical calculations,while taking far less computational time.Our findings reveal the utility of the multi-scale method in describing self-vibration,which may contribute to more efficient and accurate analyses of self-vibrating systems.展开更多
Conventional rotary actuators mainly rely on electric or hydraulic/pneumatic motors to convert energy into mechanical motion,making them one of the most widely used actuation methods in industrial manufacturing,roboti...Conventional rotary actuators mainly rely on electric or hydraulic/pneumatic motors to convert energy into mechanical motion,making them one of the most widely used actuation methods in industrial manufacturing,robotics,and automation control.However,these traditional actuators often suffer from limitations in operability and applicability due to their complex structures,bulky systems,high energy consumption,and severe mechanical wear.Liquid crystal elastomers(LCEs)have been increasingly used for programmable actuation applications,owing to their ability to undergo large,reversible,and anisotropic deformations in response to external stimuli.In this work,we propose a compact flexible rotary joint(FRJ)based on LCEs.To describe the thermo-mechanical coupled behaviors,a constitutive model is developed and further implemented for finite element analysis(FEA).Through combining experiments and simulations,we quantify the dynamic rotational behavior of the rotor rotating relative to the base driven by the induced strain of the FRJ under cyclic thermal stimuli.The proposed rotary joint features a simple structure,lightweight design,low energy consumption,and easy control.These characteristics endow it with significant potential for miniaturization and integration in the field of soft actuation and robotics.展开更多
基金supported by the National Natural Science Foundation of China(No.12172001)the University Natural Science Research Project of Anhui Province of China(No.2022AH020029)+1 种基金the Anhui Provincial Natural Science Foundation(Nos.2208085Y01 and 2008085QA23)the Housing and Urban-Rural Development Science and Technology Project of Anhui Province of China(No.2023-YF129)。
文摘Conventional liquid crystal elastomer(LCE)-based robots are limited by the need for complex controllers and bulky power supplies,restricting their use in microrobots and soft robots.This paper introduces a novel light-powered dicycle that uses an LCE rod,enabling self-rolling by harvesting energy from the environment.The LCE rod serves as the driving force,with energy being supplied by a line light source.Employing a dynamic LCE model,we calculate the transverse curvature of the LCE rod after deformation,as well as the driving moment generated by the shift in a rod’s center of gravity,which allows the dicycle to roll on its own.Through extensive numerical simulations,we identify the correlations between the angular velocity of the dicycle and the key system parameters,specifically the light intensity,LCE rod length,light penetration depth,overall mass of the dicycle,rolling friction coefficient,and wheel radius.Further,the experimental verification is the same as the theoretical result.This proposed light-powered self-rolling dicycle comes with the benefits of the simple structure,the convenient control,the stationary light source,and the small luminous area of the light source.It not only demonstrates self-sustaining oscillations based on active materials,but also highlights the great potential of light-responsive LCE rods in applications such as robotics,aerospace,healthcare,and automation.
基金supported by the National Natural Science Foundation of China(No.12172001)the University Natural Science Research Project of Anhui Province(No.2022AH020029)+1 种基金the Anhui Provincial Natural Science Foundation(Nos.2208085Y01 and 2008085QA23)the Housing and Urban-Rural Development Science and Technology Project of Anhui Province(No.2023-YF129),China.
文摘Self-vibrating systems comprised of active materials have great potential for application in the fields of energy harvesting,actuation,bionic instrumentation,and autonomous robotics.However,it is challenging to obtain analytical solutions describing these systems,which hinders analysis and design.In this work,we propose a self-vibrating liquid crystal elastomer(LCE)fiber-spring system exposed to spatially-constant gradient light,and determine analytical solutions for its amplitude and period.First,using a dynamic model of LCE,we obtain the equations governing the self-vibration.Then,we analyze two different motion states and elucidate the mechanism of self-vibration.Subsequently,we derive analytical solutions for the amplitude and frequency using the multi-scale method,and compare the solutions with numerical results.The analytical outcomes are shown to be consistent with the numerical calculations,while taking far less computational time.Our findings reveal the utility of the multi-scale method in describing self-vibration,which may contribute to more efficient and accurate analyses of self-vibrating systems.
基金Project supported by the National Natural Science Foundation of China(Nos.12125205,12321002,12132014,and 12072316)the Key Research and Development Program of Zhejiang Province of China(No.2021C01183)。
文摘Conventional rotary actuators mainly rely on electric or hydraulic/pneumatic motors to convert energy into mechanical motion,making them one of the most widely used actuation methods in industrial manufacturing,robotics,and automation control.However,these traditional actuators often suffer from limitations in operability and applicability due to their complex structures,bulky systems,high energy consumption,and severe mechanical wear.Liquid crystal elastomers(LCEs)have been increasingly used for programmable actuation applications,owing to their ability to undergo large,reversible,and anisotropic deformations in response to external stimuli.In this work,we propose a compact flexible rotary joint(FRJ)based on LCEs.To describe the thermo-mechanical coupled behaviors,a constitutive model is developed and further implemented for finite element analysis(FEA).Through combining experiments and simulations,we quantify the dynamic rotational behavior of the rotor rotating relative to the base driven by the induced strain of the FRJ under cyclic thermal stimuli.The proposed rotary joint features a simple structure,lightweight design,low energy consumption,and easy control.These characteristics endow it with significant potential for miniaturization and integration in the field of soft actuation and robotics.
