In the animal world, muscles are the basis of all movement. With commands from the brain, electrical pulses contract or release muscles, and this is how we can move our body parts. Now, researchers have created new types of actuators based on structures of multiple soft materials. Like regular actuators, these also convert electrical energy into force or motion. The advantage of these new actuators is they are lightweight, quiet in operation, and biodegradable. During the early stages of development, continuous electrical stimulation could only achieve short-term contraction of the actuators. However, new research has led to the development of a system that not only allows for longer-term contraction of the actuators but also enables accurate force measurements. These new actuators are the basis for artificial muscles.
With their ability to transform electrical energy into force or motion, the new actuators are serving an important role in everyday life. These are soft-material-based actuators, and because of their multiple functionality, have been attracting plenty of attention in the scientific community.
According to the researchers, making a soft actuator is rather simple. They use multi-material structures, in the form of pockets made of flexible films of plastic. They fill the pockets with oils and cover them with conductive plastics. Electrically activating the film results in the pocket contracting, similar to what happens in a biological muscle.
Using this technique, the researchers were able to create robotic muscles, tactile surfaces, and changeable optics. So far, using continual electrical stimulation has resulted in only short-term contractions, and this was a considerable practical barrier.
The researchers have published their findings in Nature Electronics. Researcher Ion-Dan Sirbu, at the Johannes Kepler University in Linz, along with an Austrian research group, developed a system enabling accurate measurement of force in the new actuators.
During their research on combining common materials, the researchers also experimented with plastic films that they were using for work on artificial muscles. They realized a specific combination of materials was able to sustain a constant force for long periods arbitrarily.
The team then constructed a theoretical model of the material for studying its characteristics in depth. They realized their simple model could accurately describe their experimental results. They claim their results with the simple but powerful tool will help in designing and investigating newer systems.
Their study has not only made this technology more functional, it additionally enables identifying material combinations that reduce energy consumption by a factor of thousands. With their material combinations, the researchers and other scientists have successfully investigated and developed various types of artificial muscles, tactile displays, and variable gradient optics.
The study has deepened our grasp of the basic workings of soft actuators. These advancements hold promise for significant strides in assistive devices, mobile robots, and automated machines, offering valuable contributions to marine, terrestrial, and space explorations. This is particularly crucial, given the ongoing quest in these sectors for cost-effective, high-performance solutions that prioritize low power consumption and sustainable environmental impact.
