Prime Minister Zhuge's eyes were filled with tears. Give me a thousand robots like this!

The robot dog Benben and the door frame robot in the domestic science fiction blockbuster "The Wandering Earth 2" are two very popular characters.

In the movie, Benben is called the lunar robot. It has a multifunctional mobile device that can be used on wheels and feet. It can move freely in the complex terrain of the moon. It seems to have emotional expression and intelligent judgment abilities comparable to those of a real dog. It can act cute and coquettishly to its human partners and is everyone's good friend.

The door frame robot has a simple and tough door frame-style two-legged shape. By carrying different functional modules, it can realize functions such as security inspection, fire suppression, impact protection and even rappelling diving. It is a solid backing that people can trust.

The settings of these two robots are quite innovative, but at the same time they are not purely fanciful.

This makes us look forward to it: in a few years, maybe the robot dog Benben and the door frame robot will really become a reality?

From puppets to robot dogs, the science fiction dream is gradually realized

This idea is not groundless, because in human history, there have been imaginations and attempts to create bionic robots based on the images of humans, animals, and insects for a long time.

There is a story called "Yanshi Creates Man" in the ancient Taoist work "Liezi". In the story, a carpenter named Yanshi created a puppet whose body structure is exactly the same as a real person . This can be regarded as the earliest science fiction novel in China.

According to the Mo Jing, Lu Ban invented a wooden bird, a bionic bird that could fly in the air for three days.

Zhuge Liang of the Three Kingdoms period is said to have invented a transportation device called the "wooden ox and flowing horse", which could carry goods easily along mountain roads and greatly improved the efficiency of supply transportation. Unfortunately, this skill has long been lost.

There are also many legends and literary works about robots in the mythology of Europe, America, India and other countries.

Yanshi created humans (Source: Sohu)

The development of science and technology has made these fantasies possible to become reality.

In 1495, Leonardo da Vinci designed an armored robot that could be controlled by chains and gears.

A modern replica of the robot designed by Leonardo da Vinci (Source: Wikipedia)

In the 18th century, the French inventor Vaucanson invented many bionic robots, such as the " Flute Player", "Wind Instrument Player" and "Wind Instrument Player" . Among them, the bionic duck was a huge success, and even Voltaire, Hawthorne and other writers mentioned it in their works.

The digestive duck (Source: blogspot.com)

In 1867, American Dedrick invented a cart-pulling robot that was powered by steam and could move slowly on flat ground.

Steam robot (Source: Sohu)

A four-legged walking mechanism invented by Russian Chebyshev in 1870 is considered to be the earliest recorded leg-and-foot bionic robot .

The legged walking robot invented by Chebyshev (Source: Artobolevsky, 1964)

In 1893, American Rygg applied for a patent for a mechanical horse . The driver used pedals, chains and cranks to make the horse's legs move accordingly.

Schematic diagram of the patent for the robot horse invented by Rygg (Source: Reference [1])

With the further development of science and technology in recent decades, engineers have made great progress in the design and manufacture of bionic robots, including the fish-like robot "RoboTuna", the frog-shaped bionic jumping robot that imitates frogs, and the insect-like robot fly "RoboFly". The most popular of these is the SpotMini robot dog launched by Boston Dynamics.

This is an internet celebrity product similar to the robot dog Benben. It has four legs and an additional multifunctional robotic arm. It has excellent movement and balance capabilities and can complete complex tasks such as cargo transportation, security patrols, disaster relief, etc.

The robot fish “RoboTuna” (left), the frog-shaped bionic jumping robot (center) and the robot fly “RoboFly” (right) (Image source: Reference [2])

SpotMini robot dog (Source: futura-sciences.com)

Scholars from Shandong University, Harbin Institute of Technology, National University of Defense Technology, Yushu Technology and other institutions in my country have also developed many types of robot dog products, which seems to be a "Swordsman Contest on Mount Huashan".

Robot dogs developed by Shandong University (left), Harbin Institute of Technology (center) and National University of Defense Technology (right) (Source: Sohu)

The action code of bionic robots

As the saying goes, laymen watch the excitement, while experts watch the details.

How do these amazing bionic robots move so vividly? Although they look strange in appearance, they are actually composed of three functional systems: control system, transmission system and perception system .

The control system is the brain of the bionic robot , which can send execution commands to the transmission system. This command can be sent by the operator or by the control system.

The transmission module executes the received commands through mechanical transmission components such as motors and reducers.

The perception system obtains the current motion state through various sensors and feeds the acquired information back to the control system to facilitate the control system to make the next decision .

With the coordinated action of these three systems, a simple closed-loop control system can be formed.

In fact, if you think about it carefully, this closed-loop control is also part of biological activities : our daily actions are all completed with the coordination of the brain, limbs and senses!

The robot's closed-loop control system (Source: homemade)

Developing a bionic robot is not as easy as you think!

Based on the closed-loop control system of control-mechanics-perception, engineers have adopted different structural design concepts and engineering implementation technologies to develop different types of bionic robots. However, they are faced with the same difficulties, which can be simply summarized into the following three aspects.

First of all, developing a smart enough autonomous decision-making algorithm is a major difficulty. For example, how to identify and judge whether the object in front is an obstacle or an operating object requires the use of an intelligent recognition algorithm based on images or radar; how to formulate the best detour route when encountering obstacles requires the use of a path planning algorithm; to simulate the movement patterns of different organisms, such as the swimming posture of fish, the walking posture of dogs, and the flying posture of birds, the control algorithm is required to accurately control the gait of each moving part; and when encountering emergencies, how to make autonomous judgments and make the best choice requires more complex artificial intelligence decision-making algorithms.

The 550W quantum computer in "The Wandering Earth 2" is an artificial intelligence entity with the ability to self-iterate and evolve, and its functions are very powerful. The currently popular ChatGPT is also an artificial intelligence tool based on big data learning, which has led the wave of artificial intelligence development worldwide.

550W quantum computer (source see watermark)

Secondly, developing a high-performance transmission system can avoid falling into the dilemma of "wanting to do it, but not being able to do it". The transmission system used by bionic robots mainly includes two parts: motors and reducers. The motor is used to convert electrical energy into mechanical energy. The "motor" on a toy racing car is a kind of motor. However, the output speed of the motor is very fast, which does not match the movement speed of the bionic robot, so a reducer is needed to reduce the output speed of the motor. In order to enable the bionic robot to achieve precise grasping (high transmission accuracy), lift heavy objects (strong carrying capacity), and not generate noise (low noise), engineers continue to develop various types of motors and reducers with good performance and high reliability for use in different types of bionic robots.

Harmonic reducer (left) and cycloid pinwheel reducer (right) (Image source: Reference [3])

The sensor system is the sensory organ of the bionic robot. Generally, optical sensors, ultrasonic sensors, laser radar, infrared sensors, etc. are used to accurately detect external objects and then plan obstacle avoidance paths; inertial measurement sensors can be used to sense the position and posture of the robot in the current space; force sensors are used to sense the magnitude of the force from external objects. Scientists have also invented bionic skin using pressure-sensitive flexible conductive materials to make bionic robots closer to real humans and animals.

In short, modern bionic robots have made rapid progress with the support of a large amount of black technology, which is far beyond the prototypes of early bionic robots.

If Prime Minister Zhuge Liang saw this, he would probably burst into tears: If I were given a thousand robots like this, how could I not unify the world?

References:

[1] De Santos PG, Garcia E, Estremera J. Quadrupedal locomotion: an introduction to the control of four-legged robots[M]. Springer Science & Business Media, 2007.

[2] Jian Xun. Research review and development direction of bionic robots[J]. Robotics Technology and Applications, 2022(3):17-20. DOI:10.3969/j.issn.1004-6437.2022.03.017.

[3] Xiao Yaru, Wang Mingming, Ju Liying, et al. Research progress on types and accuracy of precision reducers for robots[J]. Machine Tools & Hydraulics, 2021, 49(7): 165-171. DOI: 10.3969/j.issn.1001-3881.2021.07.032.

[4] Wang Haixia, Wu Qingfeng, Wu Xiangbin, et al. Research on the application of multi-sensor fusion in robot position perception[J]. Mechanical and Electrical Engineering Technology, 2020, 49(12): 89-91. DOI: 10.3969/j.issn.1009-9492.2020.12.026.

[5] He Huijuan, Wang Lei, Xu Dezhang. A review of the application of flexible tactile sensors in robots[J]. Sensors and Microsystems, 2015, 34(11): 5-7, 15. DOI: 10.13873/J.1000-9787(2015)11-0005-03.

Author: Liuhuo

Engineer at a research institute of weapons industry