An artificial muscle that can lift 1,000 times its own weight has been created, laying the groundwork for Terminator-like humanoid robots.
Scientists used a 3D printing technique to create the rubber-like synthetic muscle that expands and contracts like its biological counterpart.
Heated by a small electric current, the material was capable of expanding to nine times its normal size.
This is a big piece of the puzzle
Professor Hod Lipson, Columbia University
In tests it demonstrated enormous strength, having a strain density - the amount of energy stored in each gram of a stretched elastic body - 15 times greater than natural muscle.
The device, described as a "soft actuator", was able to lift 1,000 times its own weight, said the researchers whose work is reported in the journal Nature Communications.
Professor Hod Lipson, from the Creative Machines laboratory at Columbia University in New York, said: "We've been making great strides toward making robot minds, but robot bodies are still primitive.
"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."
Artificial muscles may not only be used in robots but also sensitive surgical devices and a host of other applications where gripping and manipulation is important.
Co-author Dr Aslan Miriyev, also from the Creative Machines lab, said: "Our soft functional material may serve as robust soft muscle, possibly revolutionising the way that soft robotic solutions are engineered today.
"It can push, pull, bend, twist, and lift weight. It's the closest artificial material equivalent we have to a natural muscle."
The long-term aim is to accelerate the artificial muscle's response time and link it to an artificially intelligent (AI) control system, said the researchers, who were part-funded by the Israeli defence ministry.