During the First World War, submarines were built for military needs, so that ships could sail underwater. When designing the original submarine, engineers and technicians first put stones or lead blocks on the submarine to make it sink. If it needs to rise to the surface, they will throw away the stones or lead blocks they carry with them and bring the hull back to the surface. Later, it was improved to change the weight of the submarine by alternately filling water and draining water in the buoyancy tank. Later, it was changed into a ballast tank with an exhaust valve at the upper part and a water injection valve at the lower part. When the water tank is filled with seawater, the weight of the hull increases, so that it can dive into the water. When diving is needed in an emergency, there is also a speed diving cabin. After the hull dived into the water, the seawater in the speeddive cabin was discharged. If one part of the ballast tank is filled with water and the other part is empty, the submarine can be in a semi-submersible state. When the submarine is going to float, compressed air is pumped into the water tank to discharge seawater. After the weight of seawater in the boat is reduced, the submarine can float. Such a superior mechanical device realizes the free ups and downs of the submarine. But later, it was found that the fish's undulating system was much simpler than that invented by people, and the fish's undulating system was just an inflatable swim bladder. The swim bladder is not controlled by muscles, but by secreting oxygen to the swim bladder or reabsorbing part of the oxygen in the swim bladder to adjust the gas content in the swim bladder and promote the fish to rise and fall freely. However, it is too late to inspire and help submarine designers with such an ingenious fish ups and downs system.

Sound is an indispensable element in people's lives. Through language, people exchange ideas and feelings, beautiful music makes people enjoy art, and engineers and technicians also apply acoustic system to industrial production and military technology, which becomes one of the most important information. Since the advent of submarines, it has been followed by how surface ships find the position of submarines and prevent sneak attacks; After the submarine sinks into the water, it is necessary to accurately determine the orientation and distance of the enemy ship in order to facilitate the attack. Therefore, during the First World War, various means were used in the struggle between the opposing sides in the ocean, in the water and in the water. Naval engineers also regard acoustic system as an important reconnaissance means. First of all, hydrophone, also known as noise direction finder, finds enemy ships by listening to the noise made by them when they are sailing. As long as there are enemy ships sailing in the surrounding waters, machines and propellers will make noise, which can be heard through hydrophones and find the enemy in time. But at that time, the hydrophone was not perfect, and generally it could only receive the noise of its own ship. To monitor enemy ships, it is necessary to slow down or even stop completely to distinguish the noise of submarines, which is not conducive to combat operations. Soon, the French scientist Lang Zhiwan (1872 ~ 1946) successfully explored underwater ships by using the nature of ultrasonic reflection. The ultrasonic generator emits ultrasonic waves into the water. If it meets the target, it will be reflected back and received by the receiver. According to the time interval and direction of receiving echo, the direction and distance of the target can be measured, which is called sonar system. The invention of artificial sonar system and its outstanding achievements in detecting enemy submarines have amazed people. Don't you know that bats and dolphins were free to use echolocation sonar systems long before humans appeared on the earth?

For a long time, creatures have lived in nature surrounded by sound. They use sound to find food, avoid enemies, mate and reproduce. Therefore, sound is an important information of living things. The Italian Spalanzanni discovered a long time ago that bats can fly freely in complete darkness, not only avoiding obstacles, but also preying on flying insects. However, after blocking their ears, bats can't move in the dark. Faced with these facts, Palansani came up with an unacceptable conclusion: bats can "see" with their ears. After the end of World War I, in 1920, Hatay thought that the frequency of sound signals emitted by bats was beyond the hearing range of human ears. It is also pointed out that the bat's method of locating the target is the same as the ultrasonic echo method invented by Ron Wan Zhi in the First World War. Unfortunately, Hatay's tip didn't attract people's attention, and engineers couldn't believe that bats had the technology of "echolocation". It was not until 1983 adopted an electronic measuring instrument that it was completely confirmed that bats were located by emitting ultrasonic waves. But this has not helped the early inventions of radar and sonar.

For another example, people study insect behavior too late. 400 years after Leonardo da Vinci studied bird flight and made the first plane, people finally invented the plane in 1903 after long-term repeated practice, making the dream of flying into the sky come true. Due to continuous improvement, 30 years later, human planes surpassed birds in speed, altitude and flight distance, showing human wisdom and talent. However, while continuing to develop faster and higher flying aircraft, designers have encountered another problem, that is, flutter in gas dynamics. When an airplane is flying, the wing vibration is harmful. The faster the flight speed, the stronger the flutter of the wing, and even the wing breaks, causing the plane to fall and many test pilots to die. Aircraft designers have spent a lot of energy on eliminating harmful flutter phenomenon, and it took a long time to find a solution to this problem. The weighting device is placed at the far end of the leading edge of the wing, thus eliminating harmful vibration. However, insects flew in the air as early as 300 million years ago, and they were also harmed by flutter without exception. After long-term evolution, insects have successfully obtained methods to prevent flutter. When biologists study dragonfly wings, they find that there is a dark keratin thickening area above the leading edge of each wing-wing eye or wing nevus. If the wing eye is removed, the flight will become swaying. Experiments show that it is the horny tissue of the wing eye that eliminates the danger of flapping of the dragonfly's flying wings, which is similar to the designer's superb invention. If the designer first learns the function of the wing eye from the insect, and gets a design idea that is conducive to solving the flutter, long-term exploration and personnel sacrifice can be avoided. Facing the eyes of dragonfly wings, aircraft designers have a feeling of meeting each other after a brief encounter!

The appearance of electronic computers in the 1940s added valuable wealth to the treasure house of human science and technology. It handles tens of thousands of kinds of information in people's hands with reliable and efficient skills, and liberates people from the digital and information ocean in Wang Yang. The use of computers and automation equipment can make it easy and labor-saving for people to face complicated production procedures. They accurately adjust and control the production procedures to make the product specifications accurate. However, the automatic control device works according to the fixed program formulated by people, which makes its control ability very limited. Automatic devices lack the ability to analyze and respond flexibly to the outside world. If there is any unexpected situation, the automatic device will stop working or even have an accident, which is a serious shortcoming of the automatic device itself. To overcome this shortcoming, it is nothing more than the "communication" between various parts of the machine and between the machine and the environment, that is, the automatic control device has the ability to adapt to changes in the internal and external environment. To solve this problem, how to accept and transform it in engineering technology is needed. The use and control of information. Therefore, the use and control of information has become the main contradiction in the development of industrial technology. How to solve this contradiction? The biological world has provided beneficial enlightenment to mankind.

In order to get enlightenment from biological systems, human beings need to first study whether there are * * * the same characteristics between biological and technical devices. 1940, the theory of regulation, is to compare organisms and machines in a general sense. By 1944, scientists have made it clear that a series of problems such as communication between machines and organisms, automatic control and statistical mechanics are consistent. On the basis of this understanding, 1947, a new discipline-cybernetics came into being.

Cybernetics comes from Greek, which means "turning". According to Norbert Wiener (1894 ~ 1964), one of the founders of cybernetics, cybernetics is "the science of control and communication in animals and machines". Although this definition is too simple and only a subtitle of Wiener's classic works on cybernetics, it directly relates people's understanding of biology and machines.

The basic viewpoint of cybernetics holds that there is a certain * * * between animals (especially people) and machines (including various automatic devices for communication, control and calculation), that is, there is a certain * * * same law in their control systems. According to the research of cybernetics, the control process of various control systems includes information transmission, conversion and processing. The normal operation of the control system depends on the normal information transmission process. The so-called control system means that the controlled object and various control elements, components and circuits are organically combined into a whole with certain control functions. From the information point of view, the control system is a network or system of information channels. There are many similarities between machines and control systems in organisms, so people have great interest in biological automation systems, and further research on biological systems is carried out by using physical, mathematical and even technical models. Therefore, control theory has become the theoretical basis of connecting biology and engineering technology. Become a bridge between biological system and technical system.

There are obvious similarities between organisms and machines, which can be manifested in the study of different levels of organisms. From simple single cell to complex organ system (such as nervous system), there are various physiological processes of regulation and automatic control. We can regard the organism as a machine with special abilities, which is different from other machines in that it also has the ability to adapt to the external environment and reproduce itself. You can also compare an organism to an automated factory, and all its functions follow the laws of mechanics; Its various structures coordinate their work; They can make quantitative responses to certain signals and stimuli, and they can contact the organization through special feedback like automatic control to adjust themselves in a self-controlled way. For example, our constant body temperature, normal blood pressure and normal blood sugar concentration are all the results of the complex automatic control system in our body. The emergence and development of cybernetics has built a bridge between biological system and technical system, and made many engineers consciously seek new design ideas and principles from biological system. Therefore, there is a trend that engineers take the initiative to learn biological science knowledge in order to achieve results with biologists in the field of engineering technology.

Flies and spaceships

Nasty flies seem to have nothing to do with the grand space cause, but bionics closely connects them.

Flies are notorious "smelly things". They can be seen everywhere and smell bad. Flies have a particularly sensitive sense of smell, and can smell the smell thousands of meters away. But flies don't have noses. What does it rely on to act as a sense of smell? It turns out that the "nose" of flies-olfactory receptors are distributed on a pair of antennae on the head.

Each "nose" has only one "nostril" communicating with the outside world, which contains hundreds of olfactory nerve cells. If the smell enters the nostrils, these nerves will immediately convert the smell stimulus into nerve electrical impulses and send them to the brain. The brain can distinguish substances with different smells according to different nerve electrical impulses generated by substances with different smells. Therefore, the fly's antenna is like a sensitive gas analyzer.

Inspired by this, bionics successfully imitated a very strange small gas analyzer according to the structure and function of the olfactory organs of flies. The probe of this instrument is not metal, but a live fly. A very fine microelectrode is inserted into the olfactory nerve of the fly, and the guided neuroelectric signal is amplified by an electronic circuit and sent to an analyzer; The analyzer can give an alarm as soon as it finds the signal of odorous substances. This instrument has been installed in the cockpit of the spacecraft to detect the composition of the gas in the cabin.

This small gas analyzer can also measure harmful gases in submarines and mines. This principle can also be used to improve the input device of computer and the structural principle of gas chromatography analyzer.

From Fireflies to Artificial Luminescence

Since the invention of electric light, life has become more convenient and rich. But electric lamps can only convert a small part of electric energy into visible light, and most of the rest is wasted in the form of heat energy. The heat rays of electric lamps are harmful to people's eyes. So, is there a light source that only emits light without heating? Humans have turned their attention to nature again.

In nature, many creatures can emit light, such as bacteria, fungi, worms, mollusks, crustaceans, insects and fish, and the light emitted by these animals does not produce heat, so it is also called "cold light".

Fireflies are one of many luminous animals. There are about 65,438+0,500 species of fireflies. Their luminescent colors are yellow-green, orange, and their brightness is different. Fireflies emit cold light, which not only has high luminous efficiency, but also is generally soft, suitable for human eyes, and the light intensity is relatively high. Therefore, bioluminescence is an ideal light source for human beings.

Scientists found that the luminous device of fireflies is located in the abdomen. This light emitter consists of three parts: light emitting layer, transparent layer and reflecting layer. There are thousands of luminescent cells in the luminescent layer, all of which contain fluorescein and luciferase. Under the action of luciferase, fluorescein combines with oxidation to emit fluorescence with the participation of intracellular water. The luminescence of fireflies is essentially a process in which chemical energy is converted into light energy.

As early as 1940s, people created fluorescent lamps on the basis of studying fireflies, which greatly changed the lighting sources of human beings. In recent years, scientists first isolated pure fluorescein from fireflies, then isolated luciferase, and then synthesized fluorescein artificially by chemical methods. Biological light source composed of fluorescein, luciferase, ATP (adenosine triphosphate) and water can be used as a flash lamp in mines filled with explosive gas. Because this lamp has no power supply and does not produce magnetic field, it can be used to clear magnetic mines under the irradiation of biological light source.

Now, people can get cold light similar to biological light by mixing some chemicals for safe lighting.

Electric fish and volt battery

Many creatures in nature can generate electricity, and there are more than 500 kinds of fish alone. People call these discharging fish "electric fish".

All kinds of electric fish have different discharge skills. Electric ray, electric catfish and electric eel have the strongest discharge ability. Medium-sized torpedoes can generate about 70 volts, while African torpedoes can generate up to 220 volts; African electric catfish can generate 350 volts; Electric eels can generate 500 volts. There is a South American electric eel that can generate up to 880 volts, and it is called the champion of electric shock. It is said that it can kill big animals like horses.

Where is the mystery of electric fish discharge? Through the anatomical study of the electric fish, it is finally found that there is a strange power generation organ in the electric fish. These generators are made up of many translucent disk-shaped batteries, called electric plates or plates. Due to the different types of electric fish, the shape, position and quantity of the electric plates of the generator are also different. The generator of electric eel is prismatic and located in the muscles on both sides of the caudate spine. The torpedo generator is shaped like a flat kidney, arranged on both sides of the body midline, with 2 million electric plates. The generator of electric catfish originated from some kind of gland, located between skin and muscle, with about 5 million electric plates. The voltage generated by a single plate is very weak, but because there are many plates, the voltage generated is very large.

The extraordinary skills of electric fish have aroused great interest. /kloc-at the beginning of 0/9th century, Italian physicist Volt designed the world's earliest voltaic battery based on electric fish power generation organ. Because this kind of battery is designed according to the natural generator of electric fish, the research of electric fish called "artificial electric officer" also gives people such enlightenment: if the power generation organ of electric fish can be successfully imitated, then the power problem of ships and submarines can be solved well.

Jellyfish windward ears

"Swallows fly low before the rain, cicadas sing, and the sky clears up in the rain." Biological behavior is related to the change of weather. Fishermen along the coast know that fish and jellyfish living along the coast swim to the sea in batches, which indicates that a storm is coming.

Jellyfish, also known as jellyfish, is an ancient coelenterate that floated in the ocean as early as 500 million years ago. This lower animal has the instinct to predict storms, and every time before the storm warning, it will swim to the sea to take refuge.

It turns out that in the blue ocean, infrasound (frequency is 8- 13 times per second) generated by the friction between air and waves is always a prelude to storm warning. This infrasound is inaudible to the human ear, but the little jellyfish is very sensitive. Bionics found that there is a thin handle in the ear cavity of jellyfish, a small ball on the handle, and a small auditory stone in the ball. When the infrasound before the storm hit the auditory stone in the jellyfish's ear, the auditory stone stimulated the nerve receptors on the ball wall, so the jellyfish heard the rumble of the coming storm.

Bionics imitates the structure and function of jellyfish ears, designs a storm predictor for jellyfish ears, and accurately simulates the organs that jellyfish feel infrasound. This instrument is installed on the front deck of the ship. When it receives the infrasound wave of the storm, it can automatically stop the horn rotating 360 degrees, and the direction it refers to is the direction of the storm. The reading on the indicator can show the intensity of the storm. This forecaster can forecast storms 15 hours in advance, which is of great significance to navigation and fishery safety.