Self-sustained rolling of a thermally responsive rod on a hot surface

Self-Sustained Collective Motion of Two Joint Liquid Crystal Elastomer Spring Oscillator Powered by Steady Illumination

“…Due to the unique advantages of self-excited oscillation systems, they have broad application prospects in the fields of energy acquisition, sensing with electronic skins [10], soft robotics [11][12][13], medical instruments [14][15][16][17], and motors [18]. The self-excited oscillations are generally based on responsive materials, including liquid crystal elastomers (LCEs) [19,20], dielectric elastomers [21], hydrogels [22][23][24], and ion gels [25,26]. Based on different stimuli-responsive materials and structures, different feedback mechanisms are proposed to realize energy compensation, such as the coupling of chemical reactions and large deformation [25,26], the self-shadowing effect [14,27], the coupling of liquid volatilization, and membrane deformation [28].…”

“…This special composition and structure enable LCEs to respond to external light [46][47][48][49], heat [50], electric fields [51,52], magnetic fields [53] and chemical substances [54]. Based on LCE materials, several self-exciting motion modes have been constructed, such as rolling [20], vibration [17], swinging [10,55], stretching and shrinking [56], rotation [57], eversion or inversion [9,58], torsion [59], jumping [60], and buckling [61] modes. These self-exciting motion modes provide good ideas for studying the coupling of multiple systems and their collective motion.…”

Thermally Driven Self-Rotation of a Hollow Torus Motor

“…This feature makes the self-oscillating system has no requirement of complex controllers or heavy batteries, and is simple and portable [ 22 , 23 ]. In addition, the self-sustained oscillation has robustness, and can ensure the stability and normal operation of various systems based on self-sustained oscillation [ 24 , 25 ].…”

“…In recent years, based on various stimuli-responsive materials including thermally responsive polymer materials [ 26 , 27 ], liquid crystal elastomers (LCEs) [ 28 , 29 , 30 , 31 ], dielectric elastomer [ 32 , 33 , 34 , 35 ], hydrogels [ 36 , 37 ], and ion gels [ 38 , 39 ], a wealth of self-excited motion modes have been proposed, such as rolling [ 40 , 41 ], vibration [ 24 , 31 , 40 , 41 ], torsion [ 41 , 42 ], stretching and shrinking [ 10 , 40 , 43 ], swinging [ 44 ], buckling [ 45 , 46 ], jumping [ 47 , 48 , 49 ], rotation [ 25 , 28 ], eversion or inversion [ 27 , 50 ], expansion and contraction [ 51 , 52 ], swimming [ 53 ] and even group behavior of several coupled self-excited oscillators [ 54 ]. The self-oscillating system is usually accompanied with damping dissipation, and its motion is a non-equilibrium dissipation process.…”

Self-Sustained Oscillation of a Photothermal-Responsive Pendulum under Steady Illumination

“…Self-excited oscillations have been observed in many fields of science and engineering [19][20][21][22][23] and can be utilized to produce periodic motions which are often required in numerous engineering applications [24][25][26][27][28]. Different from the forced vibration with damping dissipation, which often applies periodic stimulus to cause periodic vibration, the self-excited oscillation utilizes the nonlinear feedback within the system to result in and maintain steady-state periodic motions, such as the flapping of leaves under the breeze, the peristalsis of the digestive tract, the periodic beating of the heart, and the beautiful music produced by the violin bow.…”