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Transient thermo-mechanical analysis for bimorph soft robot based on thermally responsive liquid crystal elastomers

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Abstract

Thermally responsive liquid crystal elastomers (LCEs) hold great promise in applications of soft robots and actuators because of the induced size and shape change with temperature. Experiments have successfully demonstrated that the LCE based bimorphs can be effective soft robots once integrated with soft sensors and thermal actuators. Here, we present an analytical transient thermo-mechanical model for a bimorph structure based soft robot, which consists of a strip of LCE and a thermal inert polymer actuated by an ultrathin stretchable open-mesh shaped heater to mimic the unique locomotion behaviors of an inchworm. The coupled mechanical and thermal analysis based on the thermo-mechanical theory is carried out to underpin the transient bending behavior, and a systematic understanding is therefore achieved. The key analytical results reveal that the thickness and the modulus ratio of the LCE and the inert polymer layer dominate the transient bending deformation. The analytical results will not only render fundamental understanding of the actuation of bimorph structures, but also facilitate the rational design of soft robotics.

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Correspondence to Yuhang Li, Cunjiang Yu or Jizhou Song.

Additional information

Project supported by the National Basic Research Program (No. 2015CB351901), the National Nat- ural Science Foundation of China (Nos. 11372272, 11622221, 11621062, 11502009, and 11772030), the Doctoral New Investigator Grant from American Chemical Society Petroleum Research Fund of the National Science Foundation (Nos. 1509763 and 1554499), the Opening Fund of State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi’an Jiaotong University (No. SV2018-KF-13), and the Fundamental Research Funds for the Central Universities (No. 2017XZZX002-11)

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Cui, Y., Yin, Y., Wang, C. et al. Transient thermo-mechanical analysis for bimorph soft robot based on thermally responsive liquid crystal elastomers. Appl. Math. Mech.-Engl. Ed. 40, 943–952 (2019). https://doi.org/10.1007/s10483-019-2495-8

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  • DOI: https://doi.org/10.1007/s10483-019-2495-8

Key words

Chinese Library Classification

2010 Mathematics Subject Classification

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