Insects, the "microscopic robots" of nature. They are small in stature, agile in movement, capable of penetrating and climbing, and can go anywhere without any problem. Scientists have long thought: if only they could create a robot as flexible as an insect. However, due to the limitations of existing micro-actuator technology, artificial robotic insects always fall short, either being slow or poor in load-bearing, and even stable directional control has become a problem.
However, the research team from Beihang University has recently brought good news. They have invented a brand new micro-bionic actuator system, which not only has high energy utilization efficiency, but also can accurately control the movement of the robot. With this "black technology," they have created a robotic insect "BHMbot" that runs faster and more stably than "cockroaches." This research has been published in the journal "Nature Communications" recently.
The BHMbot with unique skills
Although this BHMbot is only 2 centimeters long and 1.76 grams in weight, it is not hollow. It integrates multiple modules such as energy, control, communication, and sensing on its body, making it a true micro-robot. The most critical thing is the special power system equipped on its legs.
Unlike traditional rotary motors, BHMbot uses a linear motor as the driving force. A linear motor is a type of electric motor that directly converts input electrical energy into linear kinetic energy, which is different from traditional torque and rotational kinetic energy. The linear motor is essentially an electromagnet that generates reciprocating vibrations when powered. At a small scale, this structure is easier to process and control. However, the vibration itself cannot directly drive the robot to walk, and a "gearbox" is needed to convert the vibration into gait movement.The research team, inspired by the joints of insect legs, designed a set of flexible hinge transmission devices. One end of the hinge is connected to the motor, and the other end is connected to the robot's leg. When the motor vibrates, the hinge will undergo elastic deformation, driving the leg to swing. At the same time, the robot's torso will also produce resonance, like a spring, ready to run.
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By carefully designing the rigidity and flexibility of the hinge and the frequency of the leg swing, researchers have achieved the resonance coupling of this flexible transmission system with the robot's body, greatly improving the robot's motion efficiency.
This combination of "linear drive + flexible transmission" can be called the "super power system" of insect robots. It cleverly avoids the various limitations of traditional rotary motors in miniaturization, and achieves efficient use of energy through bionic structure. Tests show that the efficiency of this new drive system can reach more than 20%, far higher than the level of traditional millimeter motors.
So, this little guy has an amazing "foot power". Although it can only jump a few millimeters at a time, the frequency is high. This little guy can jump dozens of times in a second, just like a spring, and the speed can reach more than 25 times its own length!
What's more magical is that this insect robot can actually run faster and faster with the "load" on its back. Even with "luggage" that is 5 times heavier than itself, it can still jump happily. This is due to its ability to automatically adjust the frequency and amplitude of jumping with changes in load. Within a certain range, the speed of BHMbot will even increase with the increase of load.As for directional control, scientists have their own ingenious solutions. They have installed miniature motors on the two legs of the BHMbot, and by cleverly adjusting the difference in the frequency of movement between the two legs, they can control the robot's direction. Just like when two wheels rotate at different speeds, the vehicle will turn. In this way, without complex mechanical structures, only two drivers can make the BHMbot "stroll" at will. The inspiration for this control method also comes from insects, which adjust their direction of travel by controlling the difference in the frequency of movement between the left and right limbs.
Endless Possibilities - The Future of BHMbot
With these "unique skills," the BHMbot is simply a "super player" in the insect world. By programming it, it can run in circles, rectangles, and even write the letters "BUAA" (abbreviation for Beihang University). With remote control from a mobile phone, it can also flexibly avoid obstacles. Such a small robot that can run and jump has many uses.
For example, it can pass through the ruins to search for survivors at the scene after an earthquake. Researchers have conducted simulation experiments, allowing the BHMbot to navigate through complex environments and successfully identify distress signals from trapped personnel. For another example, this little guy can also "check up" on airplanes. It is small in size and stable in running, making it suitable for entering narrow parts such as engines for close inspection of potential damage.
In essence, the technical principle of BHMbot is to achieve a high degree of coupling and optimization of energy conversion and motion control at a small scale. On the one hand, the clever combination of linear drive and flexible transmission has found the best "frequency" for motor output and robot movement in structural design. On the other hand, this structure can also adapt to different load and environmental requirements, automatically adjusting driving parameters to ensure that the output torque always matches the load impedance, ensuring the optimal state of energy utilization.The significance of this study lies not only in the creation of a small robot that can run fast, jump high, and is particularly capable of "carrying" loads, but more importantly in the micro-actuation and control technology it employs, which has opened up new avenues for the design of insect robots. This lightweight, agile, and efficient form of actuation is expected to bring about a revolution in the field of micro-robotics.
Drawing Inspiration from Nature in Biomimetic Mechatronics
Throughout the development process of the BHMbot, we can easily identify a core idea that has run through the history of human civilization - learning from nature, drawing inspiration from the exquisite structures of living organisms, and combining them with cutting-edge manufacturing technologies to create more efficient and intelligent machines. This intersection of bionics and robotics is an important direction for the development of the current field of robotics.
Evolution has taken hundreds of millions of years to forge the "perfect" form of insects, and engineers are now trying to use the most advanced scientific and technological means to recreate this "perfection." This is a path full of challenges, but also full of imagination.
From steam engines to electric motors, from household appliances to numerical control machines, the history of machine evolution is a history of the evolution of power systems. Now, with the emergence of micro-robots such as the BHMbot, this evolution is extending to the microscopic scale. It heralds the day when we will be able to create "micro workers" that can match or even surpass insects, creating a world composed of countless intelligent micro-robots, either working in coordination or autonomously, performing various delicate and complex tasks, serving every aspect of human society.At present, this dream remains in the realm of science fiction, but the birth of BHMbot may have already taken a crucial first step. This groundbreaking research has demonstrated the immense potential in the field of insect robotics and has also pointed out a new direction for micro power systems and control technology. What it brings to us is not only the surprise of technology but also a new imagination of the micro world.
We believe that as more and more scientists devote themselves to this field, bionic micro-robots will surely become an important force in driving the technological revolution in the near future. Let us look forward to it and expect these mechanical "insects" to create more miracles.