2023 Author: Bryan Walter | [email protected]. Last modified: 2023-05-21 22:24
Developed soft artificial muscles, set in motion by electricity and capable of lifting a load of three orders of magnitude greater than its own. The development was carried out by engineers from Columbia University, an article about it was published in the journal Nature Communications.
As a rule, motors are used as drives for robots and other mechanical devices. Some engineers are creating artificial muscle devices designed to contract and expand when stimulated. Often this stimulus is an increase or decrease in pressure using pneumatic devices. However, this approach has several limitations - for example, such artificial muscles must be supplied with a compressor.
The authors of the new development have created a soft actuator driven by electricity. It is structured as follows. Most of the actuator is an elastomer through which a metal wire runs. The elastomer also contains small bubbles of liquid ethanol. With the passage of current, the wire, and therefore the actuator itself with bubbles, heats up, due to which the ethanol, evaporating, expands in volume. If the current is then cut off, the actuator will cool down, the ethanol will condense again and its volume will decrease.
Actuator expansion principle
The process of creating a new actuator takes only a few tens of minutes. To do this, 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 with a mass three orders of magnitude larger than their own. It is worth noting that this device itself performs a function slightly different from that of living muscles, because its main action is expansion, not contraction. However, if the actuator is kept warm and cooled for contraction, then it will exactly match the muscle movements.
Last year, American researchers developed pneumatic-based artificial muscles, and recently another group of scientists created a low voltage controlled electrochemical actuator. Its principle of operation is based on the fact that voltage forces ions to be embedded between the layers of the material and thereby expand it.