Thanks to the innovations of a Chinese team, the microbot colony from Disney’s animated movie The Incredibles is one step closer to reality.
In a laboratory in Beijing, a nimble, tiny bionic robot effortlessly makes its way through the environment. When confronted with a narrow “dead end,” the insect-sized machine quickly backed away in small steps.
Professor Yang Xiaojun and his colleagues at Beihang University have created a 2 cm long insect robot that weighs less than two grams and boasts a vertical projection area the size of two fingernails.
Reducing the robot to the size of an insect is much more difficult than creating its larger counterparts, as bee-sized machines cannot be equipped with conventional motors. Therefore, the search for a miniature power system has long been a challenging quest for global researchers.
“Not using an external power source means that batteries and circuit boards have to be integrated into the robot. However, the additional load made it immobile,” says Liu Zhiwei, Yang’s former doctoral student and now an associate professor at Beihang University.
In 2009, Yang noticed a curious phenomenon: beyond a certain threshold, DC voltage caused steady vibrations, a phenomenon usually associated with AC power. This point kept replaying in his mind, hinting at a potential application, such as the wings of a tiny drone.
It wasn’t until 2017 that Yang started developing an insect-sized robot that could move without an external power source. However, over the next three years, his team explored dozens of body designs and fine-tuned the parameters, but the robot stubbornly remained in place.
To initiate the movement of his insect robot, Yang carefully studied the gaits of beetles, grasshoppers, wild horses, and rabbits.
It was the leopard’s running that provided the inspiration, and the team eventually developed a new generation of biomimetic insect robots, the “BHMbot,” capable of super-fast untethered running at speeds faster than cockroaches and with better maneuverability when turning.
In a study published last month in the journal Science Advances, they reported an updated version of the robot that can move quickly forward and backward and can perform complex running trajectories under wireless control.
A good invention usually comes from a flash of inspiration followed by a huge amount of hard research. It’s been 15 years since Yang started researching tiny robots, but his efforts have paid off.
In the experiment, the BHMbot can pass through narrow spaces and reach specific locations to perform special tasks.
Using a commercial MEMS microphone, it can successfully collect SOS sound signals from a Bluetooth speaker buried under building blocks, and the sound data is then transmitted to a computer and converted into real sound, according to Liu.
The BHMbot can also pass through the narrow passage between the two stator blades of a civilian turbofan engine and the tail section of a turbojet engine. Equipped with millimeter-scale micro-cameras, it could in the future take pictures of the inside of aircraft engines.
According to Yang, these miniature robots have promising applications in areas such as search and rescue during natural disasters, as well as in the inspection of mechanical equipment structures.
Robotic insects are also poised to take off in the future. “Our ultimate goal is to develop micro-drones with flapping wings that can fly like bees,” Yang added.
