Microscopy from Scientific Research

Time-sequential images of the microturtle gait during one movement cycle. Red dashed lines indicate the starting position. Solid and hollow arrows show the respective magnetic field directions lasting till and starting from the current time points. The elastic potential energy stored in the z picosprings independently actuates the non-magnetic torso. The presence of the non-magnetic torso helps the microturtle to avoid undesired rotation of the whole body under the magnetic field. When the left/right picosprings actuate the microturtle forwards, the right/left picosprings buffer the rotation of the torso. When the magnetic fields cycle among 0°, 15°, −75° and −105° to the axial direction of the microturtle, the microturtle gains a net displacement by utilizing the phase difference between the rotations of its left and right flippers, owing to the programmed release of the stored energy in the picospring linkages.

DOI