Muscles for the robot

Soft artificial muscles powered by electricity

Grigory Kopiev, N+1

Soft artificial muscles have been developed, driven by electricity and capable of lifting a load weighing three orders of magnitude more than its own. The development was carried out by engineers from Columbia University, an article about it was published in the journal Nature Communications (Miriyev et al., Soft material for soft actuators).

As a rule, motors are used as a drive for robots and other mechanical devices. Some engineers create devices with artificial muscles, the main task of which is to contract and expand under the influence of a certain stimulus. Often, such an incentive is an increase or decrease in pressure with the help of pneumatic devices. However, this approach has a number of limitations – for example, such artificial muscles need to be supplied with a compressor.

The authors of the new development have created a soft actuator driven by electricity. It is arranged as follows. Most of the actuator is an elastomer, through which a metal wire passes. The elastomer also contains small bubbles with liquid ethanol. During the passage of current, the wire, and therefore the actuator itself with bubbles, heat up, which is why ethanol, evaporating, expands in volume. If the current supply is then stopped, the actuator will cool down, the ethanol will condense again and its volume will decrease.

The principle of expansion of the actuator

The process of creating a new actuator takes only a few tens of minutes. To do this, you need to mix several inexpensive raw materials, pour them into a mold and wait until they harden. The authors of the development also call the use of a 3D printer an alternative to this method.

Artificial muscles based on an ethanol actuator are capable of lifting objects weighing a thousand times more than their own. It is worth noting that this device itself performs a function slightly different from the function of living muscles, because its main action is expansion, not reduction. However, if the actuator is kept in a heated state and cooled to reduce, then it will exactly match the movements of the muscles.

Recently, researchers have developed artificial muscles based on pneumatics, and recently another group of scientists has created an electrochemical actuator controlled by applying a small voltage. Its principle of operation is based on the fact that the voltage causes ions to be embedded between the layers of the material and thereby expand it.

Portal "Eternal youth" http://vechnayamolodost.ru  20.09.2017