This article is from WeChat official account: qubit (ID: techsina) , author: Xiaocha, the title picture comes from: Cornell University
In 1959, the famous physicist Richard Feynman predicted that mankind could “swallow surgeons” in the future.
Feynman is not talking about “medical troubles”, but injecting micro-robots into the human body and reaching a designated location through blood vessels for surgery.
Today, we are one step closer to this beautiful dream.
The team from Cornell University invented a miniature robot the size of a paramecium, which appeared in today’s Nature magazine.
The thickness of this robot is about 5 microns, the width is about 40 microns, and the length ranges from 40 to 70 microns. It is invisible to the naked eye and can only be observed by a microscope, which can be easily sucked into the syringe.
Through the laser irradiation control, the robot swings its front and rear legs alternately, swimming in the liquid.
Because of its small size and convenient mass production, scientists can even release thousands of such robots at a time to form an “army”.
For more than ten years, scientists have been developing micro-robots that can swim in liquids, some of which are even smaller and faster than those made by Cornell University.
So why is this new job so special?
First of all, because it uses the same process technology as manufacturing chips. A 4-inch (about 10 cm) wafer can produce more than 1 million robots.
△Micro robot structure diagram (picture from Cornell University)
Secondly, it is its special propulsion device that separates energy from the robot.
Each robot consists of the following two parts: A simple circuit made of silicon photovoltaic material, and four legs made of electrochemical actuators.
The researchers used atomic layer deposition and photolithography to construct the legs with platinum that is only a few dozen atoms thick. One side of the platinum is covered by a layer of inert titanium.
When a positive charge is applied to platinum, the negatively charged ions in the surrounding solution will be adsorbed on the exposed surface to neutralize the charge. These ions force the exposed platinum to expand and bend it.
The ultra-thin nature of the strap allows the leg to bend sharply without breaking.
To help control 3D limb movement, the researchers added rigid polymer panels to the ends of the strips. The gap between the panels is equivalent to the knee or ankle, allowing the legs to bend and move in a controlled manner.
The energy and signals for robot movement come from external lasers.
The front and rear legs of the robot are controlled by two different sets of photocells. When the photocells are illuminated by a laser, voltage is applied to the legs. By switching the laser back and forth between the two sets of photocells, the robot can be controlled to walk.
Researchers say that it only needs to generate 200 microvolts and 10 nanowatts of power to drive, so the efficiency of the propulsion device is very high, 1 million times higher than the efficiency of the robot powered by chemical energy.
Professor Itai Cohen, the corresponding author of the paper, said that although these robots have primitive functions, are not fast enough and have no computing power, they have opened the door to the intelligentization of micro robots.
Because it uses a chip manufacturing process, it can be quickly mass-produced, and it is possible to process integrated circuits on it in the future.
There is still a lot of room for micro-robots to imagine, just as Nature gave it an evaluation: Micro-action devices plus sub-millimeter circuit boards and sensors will undoubtedly bring us closer to Feynman’s vision.
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This article is from WeChat official account:qubit (ID: techsina) author: Xiao check