🧲 With an effect predicted a century ago, scientists create a motor without magnets or metals

In ferroelectric fluids, a simple electric voltage triggers a spectacular movement, capable of opposing gravity and paving the way for motors without magnets or rare metals.

The team from the Tokyo Institute of Science placed this type of special fluid between two electrodes a few millimeters (about 0.1 inches) apart. By applying a modest voltage, they observed a horizontal displacement of nearly 4 inches (about 10 centimeters), even against gravity. No tested conventional liquid showed such behavior. This result immediately sparked interest, as it demonstrates that the lateral electrostatic effect, predicted over a century ago, can finally be exploited.


The origin of this force lies in the ordered alignment of the fluid's molecules under the influence of the electric field. Unlike conventional materials where an increase in voltage produces only a small change in force, in the ferroelectric fluid the lateral thrust grows proportionally to the voltage. This linearity is a key property that allows fine control of the movement.

Building on this discovery, the team built a prototype motor operating without magnets or a metal rotor. Using only a plastic resin as the rotating part, they successfully generated rotation thanks to this lateral electrostatic force. This experimental motor runs at low voltage, making it safer and simpler than conventional electromagnetic motors.

The absence of rare metals and copper coils gives this technology a strategic advantage. Furthermore, the lack of a magnetic field opens up applications in sensitive environments such as medical imaging or data centers, where magnetic interference is problematic. The lightness of the resin rotor could also improve the responsiveness of robots and precision systems.

Professor Suzushi Nishimura admits that the idea of a fully plastic rotor seemed difficult to accept at first. But the experimental data were clear: by trusting the results, they achieved effective rotation. For him, directly observing an effect predicted over a century ago was a moment of great excitement.

This discovery upends the traditional design of motors and actuators. By replacing magnets and metals with ferroelectric materials, it becomes possible to create more environmentally friendly and less expensive devices. The potential applications are vast, from soft robots to microfluidic systems, including actuators for adaptive optics.

What is a ferroelectric fluid?

A ferroelectric fluid is a liquid that possesses a spontaneous electric polarization, similar to the magnetization of a permanent magnet. In these liquids, the molecules align in an orderly manner under the effect of an external electric field, creating a much larger electrical response than in ordinary liquids.

This property allows powerful effects, such as the lateral force observed by the researchers. Unlike ferroelectric solids, fluids can flow and adapt to complex shapes, making them ideal for flexible actuators or microsystems. Their behavior is still poorly understood, but this study paves the way for new applications.