A "robot millipede" could be used to deliver drugs to specific parts of a patient's body.
Crawling straight from the pages of a science fiction novel, the "millirobot" is engineered to travel through blood vessels.
The creators of the robot claim it will be able to deliver drugs to specific sites in the body.
It could also be used to detect toxins or find dangerous leaks in industry.
The device has a strength-to-weight ratio similar to that of an ant, with the researchers claiming it can carry 100 times its own weight.
The current prototype is 17mm long and 7mm wide.
Technology is available which could make a 100mm-long millirobot.
It would be about the width of a human hair and would move at about half a millimetre a second.
It is the latest bio-inspired robot, which mimics or draws inspiration from living organisms.
What is the millirobot made from and how does it work?
:: A blend of silicone, hexane (six carbon atoms) and magnetic iron particles creates a flexible film
:: A magnet create "legs" on one side of the film
:: The film is sliced into individual millirobots
:: Magnetic fields manipulate the body and legs of the millirobot into different shapes and mean the robot can crawl, swim and climb walls. The magnetic source needs to be within around 15m of the robot.
Using magnetic fields to move the robot means there is no need to have a fuel supply.
The robot is not currently biodegradable, but the researchers intend to create a version that will harmlessly break down inside the body.
The project has been funded by the Chinese government and carried out by the Zuankai Wang of City University, Hong Kong.
The team faces competition from a researchers in Germany who have created a 4mm-long millirobot which is as flat as a sheet of paper.
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Their device could travel through the digestive or urinary tract. It could also move through the abdominal cavity.
The German offering is not water repellent and so is less able to work in slippery or sticky environments.