Micro molybdenum disulfide actuator "force is infinite"

Chinese researchers have developed a tiny device that can pull 165 times its own weight. This new type of actuator, which can work like a muscle and convert electrical energy into mechanical energy, has broad application prospects and is expected to play a role in electromechanical systems and robot systems in the future. The research results were published in the journal Nature on Wednesday.

The super-miniature Hercules, called the Antiserial Connected Biomorphic Drive, was developed by researchers at Rutgers University in New Brunswick. The device is made of molybdenum disulfide (MoS2), an inorganic crystalline mineral compound. The researchers assembled and stacked nanosheets of molybdenum disulfide to form the device, which resembles a battery electrode. The drive is highly conductive and can insert and remove ions. The process of inserting and removing ions causes the nanosheet to expand and contract, which creates forces that trigger the movement of the flexible material. Experiments have shown that the tiny device, which weighs only 1.6 milligrams, can continuously pull 265 milligrams, or 165 times its own weight, hundreds of times without stopping.

The mechanical properties of this electrochemical device, such as stress and strain, are particularly special because of the simplicity of the process, which can be manufactured by simply stacking nanosheets. The researchers said that molybdenum disulfide nanosheets can withstand stress and strain equal to or even greater than other actuator materials after simple stacking, which is an important discovery in the field of electrochemical actuators. Such devices have great prospects in electromechanical and robotic systems. Next, they will try to scale up the device to create an actuator that can move larger objects.