Synthetic muscle step forward for soft robotics

A research team from Columbia Engineering’s Creative Machines lab developed a synthetic muscle that has a strain density 15 times larger than natural muscle and can lift 1,000 times its own weight that could propel soft robotics creation forward.

According to the study “Soft Material for Soft Actuators” published in Nature Communications, the material solves an ongoing challenge in creating lifelike soft robots because it doesn’t require an external compressor or high voltage equipment to expand. To achieve the desired high actuation stress and high strain properties, previous muscles relied on the external signal generators, which couldn’t be miniaturized to create robots that move or work independently.

“We’ve been making great strides toward making robots minds, but robot bodies are still primitive,” professor of mechanical engineering and lab lead Hod Lipson said in a press release. “This is a big piece of the puzzle and, like biology, the new actuator can be shaped and reshaped a thousand ways. We’ve overcome one of the final barriers to making lifelike robots.”

To create an actuator with the desired characteristics, researchers 3D printed the artificial muscle from the material of a silicon rubber matrix with ethanol micro-bubbles distributed throughout. The material is easy, cost-efficient and safe to make.

The unit is electrically actuated using a thin resistive wire and low power and can perform a range of motion tasks through computer controls.

“Our soft functional material may serve as robust soft muscle, possibly revolutionizing the way that soft robotic solutions are engineered today,” lead author Aslan Miriyev said in the statement. “It can push, pull, bend, twist, and lift the weight. It’s the closest artificial material equivalent we have to a natural muscle.”

The researchers plan to continue development by increasing the muscle’s response time and shelf life and studying how to use artificial intelligence to control the muscle.

Soft robotics are created to replicate natural motion to perform small tasks and to better cooperate with humans. They are expected to be especially helpful in industries like manufacturing and healthcare, which require high amounts of human-robot interaction.