Fig. 3

Actuating performance of magnetic artificial muscle controlled by an electromagnet. a Deformation amplitude of magnetic artificial muscle under an external magnetic field with (i) demonstration of testing method, variation of vertical displacement (ii) and horizontal displacement (iii) versus applied voltage, respectively, and detailed deformation with different voltage (iv). b Response time of magnetic artificial muscle under an external magnetic field with (i) demonstration of testing method and (ii) variation of luminance with the twisting behavior of artificial muscle under different frequencies