It works on methanol and uses an artificial muscle system for crawling and climbing
A beetle robot that does not require batteries
The 88-mg beetle shaped robot works on methanol. A.F.B.
Scientists have long thought about designing small robots that are able to navigate in environments that are not accessible to humans or that they pose a great danger to them, but finding a way to power them has been impossible until now.
However, a team in the Southern California community made a breakthrough in this area by designing a beetle-shaped robot weighing 88 milligrams, running on methanol, and using an artificial muscle system for crawling and climbing, and carrying cargo on its back for about two hours.
The length of this robot is only 15 millimeters, which makes it “the lightest robots that have been designed so far, and one of the most independent,” according to its inventor, Xufeng Yang.
"We wanted to create robots with a weight and size similar to real insects," said Yang, the lead author of an article describing this invention, published in the journal "Science Robotics". The problem is that robots need motors that are usually large and require electrical current, which makes batteries necessary.
The smallest batteries currently available weigh 10 to 20 times more than the tiger beetle, a 50-milligram insect that the team of scientists used as a reference in their work.
To get around this problem, Yang and his colleagues invented a synthetic muscle system based on liquid fuels and chose methanol, which has 10 times more energy than any battery of the same weight.
"Muscles" are made of wire of nickel-titanium, also known as "nentinol", whose length shrinks when exposed to heat, unlike most other metals that expand. The wire was covered with platinum powder, which acts as a catalyst for the ignition of methanol vapor.
With the combustion of the steam rising from the fuel tank in the "beetle robot (Robitel), on the platinum powder, the wire shrinks as a group of very small valves close to stop the combustion, then the wire cools and expands, which leads again to the opening of the valves to repeat the process until the fuel is completely consumed ».
Artificial muscles that expand and contract are attached to the front legs of the robot via a transport mechanism that allows it to crawl. The team tested the robot on flat and curved surfaces made of soft or rough materials such as glass.
Yang explained that "Rubitel" is able to carry a load 2.6 times its weight on the back, and to travel for two hours with a full fuel tank.
"By comparison, the smallest crawler robot with a battery weighs one gram, and works for about 12 minutes," he said.
In the future, these tiny robots may be used for a host of things, such as checking facilities, or in inspections and rescue after natural disasters. It may also assist with tasks such as artificial insemination, or environmental stewardship processes.
The robotics scientists Ryan Truby and Shungwang Lee of the Massachusetts Institute of Technology (MIT) and Harvard respectively wrote in a companion comment that "Rubitel" is "a very interesting station in small robotics", with a margin of improvement as well.
- "Rubitel" is able to carry a load of 2.6 times its weight on the back for two hours with a full fuel tank.