Solar batteries for spacecraft. How to Make a Solar Panel Rotator: Best Ideas Solar Panel Orientation System

Nowadays, many people are switching to solar lanterns for the garden, for example, or a phone charger. As everyone knows and understands, such charging works from solar energy received during the day. However, the luminary does not stand still all day, and therefore, by creating a rotating device for a solar battery with your own hands, you can increase the charging efficiency by about half by moving the battery towards the sun throughout the day.

A DIY solar panel tracker has several very significant advantages that are worth the time spent making and installing it.

1. The first and most important benefit is that rotating the solar cell throughout the day can increase the battery efficiency by about half. This is achieved due to the fact that the most efficient operation of solar panels is achieved during the period when the rays from the luminary fall perpendicularly to the photocell.
2. The second advantage of the device is created under the influence of the first. Because the battery improves efficiency and produces half as much energy, there is no need to install additional permanent batteries. In addition, the rotary battery itself may have a smaller photocell than with the stationary method. All this saves a lot of material resources.

Components of a tracker

Making your own solar panel rotator includes the same components as factory-made products.

List of required parts to create such a device:

1. The base or frame - consists of load-bearing parts, which are divided into two categories - movable and fixed. In some cases, the frame has a moving part with only one axis - horizontal. However, there are models with two axes. In such cases, actuators are needed that control the vertical axis.
2. The previously described actuator must also be included in the design and have devices not only for rotation, but also for monitoring these actions.
3. Parts are needed that will protect the device from the vagaries of the weather - thunderstorms, strong winds, rain.
4. Possibility of remote control and access to the rotary device.
5. An element that transforms energy.

But it is worth noting that assembling such a device is sometimes more expensive than buying a ready-made one, and therefore in some cases it is simplified to load-bearing parts, an actuator, and control of the actuator.

Electronic turning systems

Principle of operation

The operating principle of the rotating device is very simple and rests on two parts, one of which is mechanical and the other electronic. The mechanical part of the rotating device is respectively responsible for turning and tilting the battery. And the electronic part regulates the times and angles of inclination at which the mechanical part operates.

Electrical equipment used in conjunction with solar panels is charged from the batteries themselves, which in some way also saves money on powering the electronics.

Positive sides

If we talk about the advantages of electronic equipment for a rotary device, then it is worth noting convenience. The convenience lies in the fact that the electronic part of the device will automatically control the process of rotating the battery.

This advantage is not the only one, but is just another one in the list of those that were listed earlier. That is, in addition to saving money and increasing efficiency, electronics frees a person from the need to manually make turns.

How to make it yourself

It is not difficult to create a tracker for solar panels with your own hands, since the scheme for its creation is simple. In order to create a workable tracker circuit with your own hands, you need to have two photoresistors available. In addition to these components, you also need to purchase a motor device that will rotate the batteries.

This device is connected using an H-bridge. This connection method will allow you to convert a current of up to 500 mA with a voltage of 6 to 15 V. The assembly diagram will allow you not only to understand how a tracker for solar panels works, but also to create it yourself.

To configure the operation of the circuit, you must perform the following steps:

1. Make sure there is power to the circuit.
2. Connect the DC motor.
3. Photocells need to be installed side by side to achieve the same amount of sunlight on them.
4. It is necessary to unscrew two trimming resistors. This must be done counterclockwise.
5. The supply of current to the circuit is started. The engine should turn on.
6. We screw in one of the trimmers until it stops. Let's mark this position.
7. Continue screwing in the element until the engine begins to rotate in the opposite direction. Let's mark this position as well.
8. We divide the resulting space into equal sections and install a trimmer in the middle.
9. We screw in another trimmer until the engine starts to twitch a little.
10. We return the trimmer a little back and leave it in this position.
11. To check the correct operation, you can cover sections of the solar battery and watch the circuit’s response.

Clock turning mechanism

The design of the clock mechanism is basically quite simple. In order to create such an operating principle, you need to take any mechanical watch and connect it to a solar battery motor.

In order to make the engine work, it is necessary to install one moving contact on the long hand of a mechanical watch. The second fixed one is fixed at twelve o'clock. Thus, every hour when the long hand passes through twelve hours, the contacts will close and the motor will turn the panel.

The time period of one hour was chosen based on the fact that during this time the sun passes through the sky about 15 degrees. You can establish another fixed contact for six hours. Thus, the turn will take place every half hour.

Water clock

This method of controlling a rotary device was invented by one enterprising Canadian student and is responsible for rotating only one axis, the horizontal one.

The operating principle is also simple and is as follows:

1. The solar battery is installed in its original position when the sun's rays hit the photocell perpendicularly.
2. After this, a container of water is attached to one side, and an object of the same weight as the container of water is attached to the other side. The bottom of the container should have a small hole.
3. Through it, water will gradually flow out of the container, due to which the weight will decrease, and the panel will slowly tilt towards the counterweight. The dimensions of the hole for the container will have to be determined experimentally.

This method is the simplest. In addition, it saves material resources that would otherwise be spent on purchasing an engine, as is the case with a clock mechanism. In addition, you can install the rotary mechanism in the form of a water clock yourself, even without having any special knowledge.

Video

You will learn how to make a tracker for a solar battery with your own hands in our video.

One obvious way to improve the efficiency of solar power plants is to use solar tracking systems in them. The development of tracking systems with simple maintenance will significantly improve the technical and economic performance of agricultural facilities and create comfortable working and living conditions for people while ensuring the ecological safety of the environment. Tracking systems can be with one or two axes of rotation of solar panels.

A solar power plant with a tracking system, including a compact photoelectric sun position sensor, consisting of a frame in the shape of a straight triangular prism, on two side faces of which photocells for tracking the sun are located, and on the third face there is a command photocell for turning the modules from west to east. During daylight hours, tracking photocells on the edges of the sensor issue command signals to the control unit for the azimuthal rotation drive of the solar module, which rotates in the direction of the sun using a shaft. The disadvantage of the installation is the insufficient accuracy of tracking the sun.

The solar power plant contains a solar battery with a biaxial orientation system to the sun, on which photoelectric modules containing linear photodetectors located at the foci of cylindrical Fresnel lenses are installed as sun tracking sensors. Signals from photodetectors, using a microprocessor, control the drives of the azimuthal and zenithal orientation system of the solar battery.

The disadvantage of this installation is the insufficient accuracy of tracking the sun, as well as the fact that the tracking sensors occupy part of the active area of ​​the solar battery.

The main goal of the development is to improve the accuracy of the sun tracking sensor for biaxial solar panel orientation systems at any position of the sun in the sky throughout the year.

The above technical result is achieved by the fact that in the proposed sun tracking sensor there is a biaxial orientation system for a solar battery, containing a block of beam-receiving cells installed on a fixed platform, which are made in the form of reverse cones with opaque walls and mounted on the narrow ends of the cones of photoelectric cells. In this case, the beam-receiving cells are tightly installed on the platform with the formation of a solid angle of 160° and framed by a transparent sphere mounted on the platform, which is installed with an inclination to the horizontal at an angle equal to the geographic latitude of the sensor location.

The tracking sensor is installed on a stationary platform, the normal 6 of which (Fig. 1) is directed to the south. The angle of inclination of the site to the horizontal base corresponds to the geographic latitude of the area next to the solar battery, placed on a mechanical solar orientation system containing zenithal and azimuthal rotation drives using stepper gear motors. The solar battery drives are controlled by a microprocessor that receives electrical impulses from the photoelectric elements of the sensor cells. The microprocessor contains information about the geographic latitude of the location of the solar battery, an electronic clock equipped with a calendar, the signals of which activate the gear motors for the zenithal and azimuthal rotation of the solar battery in accordance with the equation of the movement of the sun in the sky. In this case, the values ​​of the achieved rotation angles of the solar battery based on the signals from the photoelectric elements of the sensor cells are compared with the values ​​​​obtained from the equation of motion of the sun at the current time.

The essence of the sensor design is illustrated in Fig. 1, 2, 3 and 4. In Fig. 1 and 3 show the general diagram of the sensor. In Fig. Figure 2 shows a top view of a transparent sphere and beam-receiving cells. In Fig. Figure 4 shows a diagram of such a cell.

The sun tracking sensor for a biaxial solar panel orientation system contains a platform 1 attached to a horizontal base 5 at an angle a equal to the latitude of the area. A transparent hemisphere 2 with a radius r is attached to the platform 1. In the entire internal space of the sphere 2, beam-receiving cells 3 are closely fixed, having the shape of an inverse cone with opaque walls 7, facing the inner wall of the transparent sphere 2 with a diameter φ, and a diameter d 2 to site 1. The height of cone 3 is equal to the distance h from the inner wall of the sphere 2 to the surface of the platform 1. In the lower part of the cone 3 at a distance of 5d 1 from the upper edge of the cone 3 there is a photoelectric element 4, the electrical signal from which is transmitted to the microprocessor system for controlling the rotation of the solar battery axes (not shown in Fig. 1) . The distance 5d 1 is selected in such a way that the sun's ray 8 is accurately captured on the photoelectric element 4, limited by the opaque walls 7 of the cone 3.

The sun tracking sensor works as follows. The sun's rays 8 penetrate through the transparent sphere 2, the internal space of the cone 3 and fall on the photovoltaic element 4, causing an electric current, which is analyzed by the microprocessor and transmitted to the stepper motor-gear drives of the solar battery orientation system (not shown in the figure). As the sun moves across the sky, its rays 8 gradually turn on the photoelectric elements 3 and contribute to the precise and smooth regulation of the rotation of the solar battery along the azimuthal and zenithal axes.

Laboratory tests of the sensor cell layout using a solar radiation simulator showed acceptable results of cutting off the luminous flux for the accepted values d 1 , d 2 and 5 d x.

The sun tracking sensor of a biaxial solar battery orientation system contains beam-receiving cells made in the form of inverse cones, tightly installed on the site to form a solid angle of 160° and framed by a transparent sphere, allowing for more accurate orientation of solar panels and thereby receiving the greatest amount of electricity from them .

In the construction of country houses, houses on summer cottages, greenhouses, and various farm buildings, autonomous power supply systems have increasingly begun to be used. Solar panels provide independence from general electrical networks. And in cities in the private sector you can often see solar panels of home power plants on the roofs of houses.

These panels can be with mono- and polycrystalline silicon structures, can be built on the basis of batteries made using amorphous or micromorphic technology, and can even use solar cells made using “Moth Eye” technology. Moreover, each building is built in such a way that solar panels are installed in a place that receives maximum sunlight.

The efficiency of modern helium systems on average does not exceed 18% - 20%. The best samples can achieve 25% efficiency. In 2014, scientists at the UNSW Australian Center for Advanced Photovoltaics reported that they had achieved solar cell efficiency of 40%.

It should be understood that the efficiency value is measured when the helium panel is illuminated by the sun at right angles. If the solar battery is fixed permanently, then during the day, when the sun moves across the sky, the period of direct illumination of the battery by the sun will be relatively short. And therefore, the efficiency of even the most advanced solar panels will decrease.

In order to minimize the decrease in the efficiency of helium systems, solar panels should be installed on rotating modules, which will allow the batteries to be oriented towards the sun throughout the day. Such a rotating device, on which a supporting structure with one or more solar panels is attached, is called a tracker.

It is designed to monitor the sun and, depending on its position, orient the solar panel towards it. This device, depending on the version, includes one or two sun tracking sensors, as well as a rotating mechanism. The tracker must be installed in a well-lit place on the ground, on a stationary stand, or on a mast that will raise the tracker to such a height that the solar battery is always illuminated by the sun.

Tracker with four solar panels on a mast

Even the simplest rotating device with a sun tracking system allows you to get maximum efficiency from gel batteries. Studies have shown that in the absence of proper orientation of solar panels to the sun, up to 35% of power is lost. Therefore, in order to reach the planned power in the case of fixed mounting of photocells, it is necessary to install a larger number of panels.

The principle of constructing solar panel rotation control systems

The industry produces several types of solar panel rotation control systems. These are quite expensive (up to 100,000 rubles) devices that can control the position of several helium panels at once.

Since the sun moves not only horizontally but also vertically during the day, these control systems monitor both changes in position and, in accordance with the information received, issue commands to rotate the panel around the horizontal or vertical axes. In the general case, such a control system consists of a solar sensor, a signal converter (P) from this sensor, a signal amplifier (U), a microcontroller (MC), an engine control device (ECD), the engine itself and, finally, the frame itself on which it is mounted. helium panel.

Tracker control circuit

It is characteristic that the same circuit is used to control rotation in both axes. Only the sun position sensors and motors are different. The simplest sun position sensor consists of two photodiodes separated by an opaque partition.

Depending on what movement this sensor monitors, the partition is installed horizontally or vertically, but must be directed strictly towards the sun. As long as both photodiodes are illuminated equally, the signals coming from them are equal. As soon as the sun moves so much that one of the photodiodes is in the shadow of the partition, an imbalance of signals occurs and the control system generates a corresponding command to rotate the solar panel.

Sun position sensor circuit

As a rule, stepper motors or reluctance valve motors are used as motors for the turntable. In such control systems, tracking sensors are installed on the same platform and rotate with it, thereby ensuring precise orientation of the helium panel to the sun. For reliable operation of the sensor, it is necessary to protect it from contamination, snow accumulation, and shading of the optics by random objects.

There are control systems in which tracking sensors are removed from the supporting rotating platform and are located in a place protected from such influences. In this case, the signal from the sensors is sent to the synchronizer transmitter. By orienting the tracking sensor towards the sun, the synchro-transmitter transmits the control action to the synchro-receiver, which rotates the supporting platform, pointing it exactly at the sun.

Solar panel rotation control system based on a clock mechanism

Industrial installations - fully equipped helium power plants with biaxial rotary modules - are quite expensive. For example, the UST-AADAT industrial tracker costs about one and a half million rubles. The natural desire of all solar power plant owners is to increase power output while reducing costs. As a result, homemade devices appeared, original in their design, using scrap materials. And these devices quite successfully control the orientation of the panels to the sun.

One of the options for such a device is a system for controlling the orientation of helium panels, built on the basis of a clock mechanism. To track the sun, it is not at all necessary to use light-receiving devices. To do this, just take an ordinary mechanical wall clock. Even old walkers will do. It is known that in one hour the sun travels across the sky from east to west a path corresponding to an angular displacement of 15°. Since such angular displacement is not particularly critical for a helium panel, it is enough to turn on the rotating mechanism once an hour.

Tracking the movement of the sun by clock

A device for rotating a helium panel around a vertical axis may look like this. A fixed contact is established in the dial at a distance of the length of the minute hand from the center, at the place corresponding to 12 o'clock. The moving contact is at the tip of the minute hand.

Thus, every 60 minutes the contacts will close and the motor will turn on, turning the solar panel. The engine can be switched off in various ways, for example, using a limit switch or a time relay. If you install another fixed contact on the dial at the place corresponding to 6 o'clock, then the panel position will be corrected every half hour.

In this case, the engine shutdown devices must be set to rotate the carrier platform at an angle of 7.5°.

In addition, if desired, here, on this mechanism, with the help of another contact group, but on the clockwise basis, you can assemble a circuit for automatically returning the solar panel to its original position. Based on the same clockwise hand, you can assemble a control system for rotating the panel around the horizontal axis. While the hour hand moves to 12 o'clock, the supporting frame rises with the sun. After 12 hours, the horizontal axis motor is reversed and the solar panel begins to rotate in the opposite direction.

Water clock principle in solar panel rotation control system

This system was invented by nineteen-year-old student Eden Full from Canada. It is designed to control a single-axis tracker. The operating principle is as follows. Rotation is performed around a horizontal axis. The solar panel is installed in the initial position so that the sun's rays are perpendicular to the plane of the panel.

A container with water is suspended on one side of the panel, and a load is suspended on the opposite side, which is in equilibrium with the container filled with water. A small hole is made in the bottom of the container so that water flows out drop by drop from this container. The size of this hole is selected experimentally. As the water flows out, the vessel becomes lighter, and the counterweight slowly turns the frame with the panel.

Water clock tracker

Preparing the tracker for operation consists of pouring water into the empty container and placing the solar panel in its original position.

These two examples do not exhaust the possible options for constructing rotary modules. With a little imagination, you can get a simple but very effective device that is guaranteed to increase the efficiency of your home helium power plant.

The Roman philosopher Seneca said: “If a person does not know where he is sailing, then there is no favorable wind for him.” In fact, what use is it to us if we do not know the position of the device in space? This story is about devices that allow us not to get lost in space.

Technological advances have made attitude control systems small, cheap and accessible. Now even a student microsatellite can boast an orientation system that the pioneers of astronautics could only dream of. Limited opportunities gave rise to ingenious solutions.

Asymmetrical answer: no orientation

The first satellites and even interplanetary stations flew unoriented. Data transmission to Earth was carried out via a radio channel, and several antennas, so that the satellite could be in touch at any position and any tumbles, weighed much less than the attitude control system. Even the first interplanetary stations flew unoriented:

Luna 2, the first station to reach the lunar surface. Four antennas on the sides provide communication at any position relative to the Earth

Even today, it is sometimes easier to cover the entire surface of a satellite with solar panels and install several antennas than to create an attitude control system. Moreover, some tasks do not require orientation - for example, cosmic rays can be detected in any position of the satellite.

Advantages:

• Maximum simplicity and reliability. A missing orientation system cannot fail.

Flaws:

• Currently suitable mainly for microsatellites that solve relatively simple problems. “Serious” satellites can no longer do without an attitude control system.

Solar sensor

By the middle of the 20th century, photocells had become a familiar and mastered thing, so it is not surprising that they went into space. The Sun became an obvious beacon for such sensors. Its bright light fell on the photosensitive element and made it possible to determine the direction:

Various operation schemes of modern solar sensors, at the bottom there is a photosensitive matrix

Another design option, here the matrix is ​​curved

Modern solar sensors

Advantages:

• Simplicity.


• Cheapness.


• The higher the orbit, the smaller the shadow area, and the longer the sensor can operate.


• The accuracy is approximately one arc minute.

Flaws:

• Do not work in the shadow of the Earth or other celestial body.


• May be subject to interference from the Earth, Moon, etc.

Just one axis along which solar sensors can stabilize the device does not interfere with their active use. Firstly, the solar sensor can be complemented with other sensors. Secondly, for spacecraft with solar batteries, the solar sensor makes it easy to organize a rotation mode on the Sun, when the device rotates aimed at it, and the solar batteries operate in the most comfortable conditions.
The Vostok spacecraft cleverly used a solar sensor - the axis on the Sun was used when constructing the orientation to decelerate the ship. Also, solar sensors were in great demand on interplanetary stations, because many other types of sensors cannot operate outside of Earth orbit.
Due to their simplicity and low cost, solar sensors are now very common in space technology.

Infrared vertical

Vehicles that fly in Earth orbit often need to determine the local vertical - the direction towards the center of the Earth. Visible photocells are not very suitable for this - on the night side the Earth is much less illuminated. But, fortunately, in the infrared range, the warm Earth shines almost equally on the day and night hemispheres. In low orbits, sensors determine the position of the horizon; in high orbits, they scan the space in search of the warm circle of the Earth.
Structurally, as a rule, infrared vertical plotters contain a system of mirrors or a scanning mirror:

Infrared vertical assembly with flywheel. The unit is designed for precise orientation to the Earth for geostationary satellites. The scanning mirror is clearly visible

An example of the field of view of the infrared vertical. Black circle - Earth

Domestic infrared verticals produced by JSC "VNIIEM"

Advantages:

• Capable of building a local vertical in any part of the orbit.


• Generally high reliability.


• Good accuracy -

Flaws:

• Orientation on one axis only.


• For low orbits, certain designs are needed, for high orbits, others.


• Relatively large dimensions and weight.


• Only for Earth orbit.

The fact that the orientation is constructed along only one axis does not prevent the widespread use of infrared verticals. They are very useful for geostationary satellites that need to point their antennas towards the Earth. ICRs are also used in manned cosmonautics, for example, on modern modifications of the Soyuz spacecraft, orientation to braking is carried out only according to its data:

The Soyuz ship. Duplicate SCI sensors are shown by arrows

Gyroorbitant

In order to issue a braking impulse, it is necessary to know the direction of the orbital velocity vector. The solar sensor will give the correct axis approximately once a day. This is normal for astronaut flights; in case of an emergency, a person can manually orient the ship. But the Vostok ships had “twin brothers”, the Zenit reconnaissance satellites, which also needed to issue a braking impulse in order to return the captured film from orbit. The limitations of the solar sensor were unacceptable, so something new had to be invented. This solution was the gyroorbitant. When the infrared vertical works, the ship rotates because the axis to Earth is constantly turning. The direction of orbital motion is known, so by the direction in which the ship turns, its position can be determined:

For example, if the ship constantly rolls to the right, then we are flying right side forward. And if the ship flies stern forward, then it will constantly raise its nose up. With the help of a gyroscope, which tends to maintain its position, this rotation can be determined:

The more the arrow is deflected, the more pronounced the rotation along this axis. Three such frames allow you to measure rotation along three axes and turn the ship accordingly.
Gyroorbitants were widely used in the 60s-80s, but are now extinct. Simple angular velocity sensors made it possible to effectively measure the rotation of the vehicle, and the on-board computer could easily determine the position of the ship from these data.

Ion sensor

It was a nice idea to supplement the infrared vertical with an ion sensor. In low Earth orbits, there are atmospheric molecules that can be ions - carrying an electrical charge. By installing sensors that record the flow of ions, you can determine which side the ship is flying forward in orbit - there the flow will be maximum:

Scientific equipment for measuring the concentration of positive ions

The ion sensor worked faster - it took almost a whole orbit to build an orientation with a gyroorbitant, and the ion sensor was able to build an orientation in ~10 minutes. Unfortunately, in the area of ​​South America there is a so-called “ion well”, which makes the operation of the ion sensor unstable. According to the law of meanness, it is in the area of ​​South America that our ships need to focus on braking for landing in the Baikonur area. Ion sensors were installed on the first Soyuz, but they were abandoned soon enough, and now they are not used anywhere.

Star sensor

One axis on the Sun is often not enough. For navigation, you may need another bright object, the direction of which, together with the axis to the Sun, will give the desired orientation. The star Canopus became such an object - it is the second brightest in the sky and is located far from the Sun. The first spacecraft to use a star for orientation was Mariner 4, which launched to Mars in 1964. The idea turned out to be successful, although the star sensor drank a lot of the MCC's blood - when constructing the orientation, it was aimed at the wrong stars, and it was necessary to “jump” over the stars for several days. After the sensor finally aimed at Canopus, it began to constantly lose it - debris flying next to the probe would sometimes flash brightly and restart the star search algorithm.
The first star sensors were photocells with a small field of view that could be aimed at only one bright star. Despite their limited capabilities, they were actively used on interplanetary stations. Now technological progress has, in fact, created a new class of devices. Modern star sensors use a matrix of photocells, work in tandem with a computer with a catalog of stars, and determine the orientation of the device based on those stars that are visible in their field of view. Such sensors do not require preliminary construction of a rough orientation by other devices and are able to determine the position of the device regardless of the area of ​​​​the sky to which they are sent.

Typical star trackers

The larger the field of view, the easier it is to navigate

Illustration of the sensor operation - the direction of view is calculated based on the relative positions of the stars according to the catalog data

Advantages:

• Maximum accuracy, can be less than an arc second.


• Does not need other devices, can determine the exact position independently.


• Work in any orbits.

Flaws:

• High price.


• They do not work when the device is rotated quickly.


• Sensitive to light and interference.

Now star sensors are used where it is necessary to know the position of the device very accurately - in telescopes and other scientific satellites.

Magnetometer

A relatively new direction is the construction of orientation according to the Earth's magnetic field. Magnetometers for measuring the magnetic field were often installed on interplanetary stations, but were not used to plot orientation.

The Earth's magnetic field allows you to build orientation along all three axes

"Scientific" magnetometer of the Pioneer-10 and -11 probes

The first digital magnetometer. This model appeared on the Mir station in 1998 and was used in the Philae lander of the Rosetta probe.

Advantages:

• Simplicity, cheapness, reliability, compactness.


• Average accuracy, from arcminutes to several arcseconds.


• You can build orientation along all three axes.

Flaws:

• Subject to interference, including and from spacecraft equipment.


• Does not work above 10,000 km from Earth.

The simplicity and low cost of magnetometers have made them very popular in microsatellites.

Gyro-stabilized platform

Historically, spacecraft often flew unoriented or in solar spin mode. Only in the area of ​​the mission target did they turn on active systems, build orientation along three axes, and complete their task. But what if we need to maintain voluntary orientation for a long time? In this case, we need to “remember” the current position and record our turns and maneuvers. And for this, humanity has not come up with anything better than gyroscopes (measure rotation angles) and accelerometers (measure linear accelerations).
Gyroscopes
The property of a gyroscope to strive to maintain its position in space is widely known:

Initially, gyroscopes were only mechanical. But technological progress has led to the emergence of many other types.
Optical gyroscopes. Optical gyroscopes - laser and fiber optic - are distinguished by very high accuracy and the absence of moving parts. In this case, the Sagnac effect is used - a phase shift of waves in a rotating ring interferometer.

Laser gyroscope

Solid State Wave Gyroscopes. In this case, the precession of a standing wave of a resonating solid is measured. They contain no moving parts and are very accurate.

Vibration gyroscopes. They use the Coriolis effect for operation - vibrations of one part of the gyroscope when turning deflect the sensitive part:

Vibrating gyroscopes are produced in the MEMS version; they are inexpensive and very small in size with relatively good accuracy. It is these gyroscopes that are found in phones, quadcopters and similar equipment. A MEMS gyroscope can also operate in space, and they are installed on microsatellites.

The size and accuracy of gyroscopes is clear:

Accelerometers
Structurally, accelerometers are scales - a fixed load changes its weight under the influence of accelerations, and the sensor converts this weight into an acceleration value. Now accelerometers, in addition to large and expensive versions, have acquired MEMS analogues:

An example of a "large" accelerometer

Micrograph of a MEMS accelerometer

The combination of three accelerometers and three gyroscopes allows you to record rotation and acceleration in all three axes. Such a device is called a gyro-stabilized platform. At the dawn of astronautics, they were only possible on a gimbal and were very complex and expensive.

Apollo gyro-stabilized platform. The blue cylinder in the foreground is a gyroscope. Platform testing video

The pinnacle of mechanical systems were cardless systems, when the platform hung motionless in gas flows. It was high-tech, the result of the work of large teams, very expensive and secret devices.

The sphere in the center is a gyro-stabilized platform. Peacekeeper ICBM guidance system

Well, now the development of electronics has led to the fact that a platform with precision suitable for simple satellites fits in the palm of your hand, it is being developed by students, and even the source code is published.

MARG platforms have become an interesting innovation. In them, data from gyroscopes and accelerometers is supplemented with magnetic sensors, which makes it possible to correct the accumulating error of the gyroscopes. The MARG sensor is probably the most suitable option for microsatellites - it is small, simple, cheap, has no moving parts, consumes little power, and provides three-axis orientation with error correction.
In “serious” systems, star sensors are usually used to correct orientation errors of a gyro-stabilized platform.

The invention relates to space technology and can be used on spacecraft for various purposes. The proposed solar panel consists of a frame, beam and upper and lower sashes. The doors are secured to the frame, beam and body of the spacecraft using pyrolocks with pawls and are connected to each other by clamps. In this case, a pyroelectric element is additionally installed in the body of each pyrolock, which autonomously interacts with the pawl, in which a second hole is made for an additional axis. A latch is hinged on the lower sash, one end interacting with a bracket rigidly fixed to the upper sash, and the other end with the end of the corresponding latch. In the proposed design, the pyro-medium is used simultaneously to fasten the package of shutters to the frame and beam, as well as the frame and beam to the spacecraft body. As a result, the invention makes it possible to increase the reliability of opening the solar panel shutters by approximately 100 times. 11 ill.

The invention relates to space technology and can be used on spacecraft for various purposes. A known solar battery (SB) of the spacecraft developed by TsSKB Samara, drawings 11f624 8700-0, the general view of which is shown in Fig. 1 prototype. In fig. Figure 2 shows a cross section of the battery (section AA). In fig. Figure 3 shows a cross-section of the pyrochemical (B-B). In fig. 4 shows an element for fixing the valves, and Fig. 5 of the prototype shows the solar battery in working (opened) position. On the body of the spacecraft 1 (Fig. 1) a drive 2 is rigidly fixed, to the output shaft of which a power frame 3 is attached. On the body of the spacecraft there is installed equipment 4 (Fig. 2), which, together with the area under the fairing, determined the configuration of the battery in the stowed position. On the frame 3 and beam 5 (Fig. 1), using a hinged parallelogram 6 (Fig. 2), lower doors 7 and upper doors 8 are installed, secured on one side with a latch 9 (Fig. 4 of the prototype), and on the other side connected by a hinge 10 , Frame 3 and beam 5 with pyrochemicals 11 fig. 1 are fixed on the spacecraft body. The pyroelectric device 11 is a housing 12, a pawl 13, a torsion spring 14, a pyroelement 15 (for example, a pyrobolt), which, with the pawl 13, presses the frame 3 and beam 5 (Fig. 1) to the body of the spacecraft 1. In the body of the pyroelectric device 12 (Fig. 3) and the pawl 13 has a hole 16 for the main axis 17. Using pyroelements 11 (Fig. 2) of a similar design using the same pyroelements 15 (Fig. 3), the lower doors 7 (Fig. 2) are attached to the frame 3 and beam 5 (Fig. 1 ) at six power points. On one of the hinges of the parallelogram 6 (Fig. 2) a cam 18 (Fig. 4) is rigidly mounted, which rests against a spring-loaded latch 9, which holds the doors 7 and 8 in the locked position. A mesh fabric is stretched along the perimeter of each door 7 and 8, on which photoelectric converters 19 are fixed (Fig. 5). The disclosure of the Security Council occurs in the following sequence. After the head fairing is released, a command is given to activate the pyroelements 15 (Fig. 3) of the pyroelectric device 11. Along the separation plane, the pyroelement 15 is torn. The pawl 13 is rotated by a torsion spring 14 in the hole 16 relative to the main axis 17. The connection between the frame 3, beam 5 (Fig. 3) and the body of the spacecraft 1 (Fig. 1) is broken. Drive 2 moves the SB panel away from the SC body 1 and stops. A command is given to trigger the pyroelectric element 15 (Fig. 3) of the pyroelectric device 11 (Fig. 2). The connection between the lower flap 7, frame 3 and beam 5 (Fig. 1) is broken. Under the action of torsion springs installed in the G axes (Fig. 2) hinged parallelogram 6, the flaps 7 and 8 begin plane-parallel movement in the axes of the hinged parallelogram 6. The cam 18 (Fig. 4), rigidly fixed to the hinge, at a certain angle of rotation of the flaps 7 and 8 releases the spring-loaded latch 9, which, moving in the axial direction, unlocks the sash 8 relative to the sash 7. The sash 8 rotates relative to the hinge 10, and the sash 7 continues its plane-parallel movement until it is fixed on the frame 3 (Fig. 1) and the beam 5. The sash 8 (Fig. 4) is fixed in the hinge 10 with the sash 7. Thus, all four doors open and lock, forming a single flat panel. Drive 2 (Fig. 1) rotates the panel to the optimal position relative to the Sun. The disadvantage of the described design is the low reliability of opening the valves. The presence of a large number of pyroelements reduces the likelihood of failure-free operation of the deployment system. To open one SB panel, it is necessary to trigger 12 pyroelements (pyrobolts). In accordance with the technical specifications for them, P bolt = 0.99996, and for 12 P systems = 0.99996 12 = 0.99952 This means, approximately, 1 failure per 1000 products. In addition, the axial movement of the latch when the base holes in different sashes are displaced due to their thermal deformations is prone to “biting”, which leads to the non-opening of the sashes. The objective of the present invention is to increase the reliability of opening the security shutters by introducing duplication elements. The problem is solved by the fact that in the body of each pyroelectric device (lock) a pyroelement is additionally installed that interacts with the pawl, and a swinging latch is hinged on the lower sash, one end abuts against a bracket rigidly fixed to the upper sash, and the other interacts with the end of the latch. In fig. 6 shows a general view of the SB; in fig. 7 - cross section of SB; in fig. 8 - element for fixing the upper and lower sashes; in fig. Figure 9 shows a pyro device (lock) securing the lower SB door with frame and beam to the spacecraft body; in fig. 10 shows the position of the working link after activation of the main pyroelement (squib); in fig. 11 - position of the working link after activation of the additional pyroelectric element (squib). The solar battery is installed on the body 20 (Fig. 6) of the spacecraft. A power frame 22 is rigidly attached to the drive 21. The equipment, for example, an antenna 23, is placed between the frame 22 and the beam 24. On the frame 22 and the beam 24 using a hinged parallelogram 25 (Fig. 7) the lower 26 and upper 27 sashes are installed. The lower flap 26, connected to the flap 27 by a spring-loaded hinge 28, is pressed against the body 20 (Fig. 6) by means of fire 29 (Fig. 9). Thus, the pyro-means 29 are pressed against the body of the spacecraft 20 (Fig. 6), the flaps 26 (Fig. 7), the frame 22 (Fig. 6) and the beam 24. In the body 30 (Fig. 9) of each pyro-means 29 there is a hole 31 for the main axis 32 and a pyroelement 33 (squib) is installed, which, interacting with the axis 32, fixes the lever 34 relative to the body 30. An additional pyroelement 35 (Fig. 11) is installed in the body 30, interacts with the additional axis 36 (Fig. 10) and fixes the lever 34 with a housing 30 (Fig. 9) and a pawl 37. Its own axis 38 fixes the lever 34 relative to the pawl 37 and ensures their joint rotation relative to the additional axis 36 (Fig. 10) in the housing 30 (Fig. 9), in which a figured groove 39 is made The spring pusher 40 rests against the lever 34, and the pawl 37 interacts with the cocked torsion spring 41. On the sash 26 (Fig. 8) there is a latch 43 spring-loaded in the axis 42, one end of which rests against the end 44 of the spring-loaded latch 45, held in the working position cam 46. The other end of the latch 43 keeps the flap 27 from opening. The work of the spacecraft is carried out in the following sequence. After dropping the head fairing, based on the functional tasks of the spacecraft, the antenna 23 (Fig. 7) with its drive is removed from the body of the spacecraft 20 (Fig. 6) from the SB deployment zone and is fixed in the working position. Thus, antenna 23 (Fig. 7) frees up the area for opening the shutters 26 and 27 on board the spacecraft. It has become possible to use a pyro product for: - attaching a package of sashes to the frame and beam and for their subsequent opening; - fastening the frame and beam to the spacecraft body and their subsequent separation. Using one pyro product to solve two problems allows you to reduce their number, which increases the reliability of the system. A command is given to activate the main pyroelement 33 (Fig. 9) of the pyroelectric device 29. The main axis 32, moving in the axial direction, “sinks” into the housing 30. The lever 34 is under the force of the compressed spring of the pusher 40 together with the pawl 37 (Fig. 10) and its own axis 38 rotates relative to the additional axis 36. In this case, the axis 38 moves in the cavity of the figured groove 39. Without analyzing the operation of the pyroelectric device, a command is sent from the main pyroelectric element 33 after 0.5-2 s to the backup pyroelectric element 35 (Fig. 11). Under the influence of its powder gases, the additional axis 36 “sinks” (Fig. 10), the pawl 37 is rotated relative to the main axis 32 by a torsion spring 41. The doors 26 and 27 (Fig. 7), the frame 22 (Fig. 6) and the beam 24 are released from the body of the spacecraft 20, opened under the action of torsion springs installed in the axes of the hinge parallelogram 25 (Fig. 7). The panel is moved by drive 21 to the working position. The pawl 37 (Fig. 10) does not protrude beyond the “y” plane and does not prevent the removal of the SB elements from the spacecraft body. The cam 46 (Fig. 8), rigidly fixed to the hinge, at a certain angle of rotation releases the latch 45, which, moving in the axial direction, releases the shank of the latch 43. Rotating with a torsion spring, the latch 43 releases the flap 57, which opens and locks. During mutual movements of the valves due to overloads and temperature changes, the end 44 of the latch 45 has the ability to move along the square. "I", which eliminates the non-opening of the valves. Due to the fact that two independent mechanisms are installed in the body of the pyroelectric device 30 (Fig. 9), triggered by pyroelements (squibs) 33 and 35 (Fig. 11), the reliability of operation of the pyroelectric device increases and amounts to
P o = 0.999999
And since we managed to solve the problem of fastening and opening the sashes with 6 pyrotechnics (instead of 12), the reliability of opening the sashes is
P system = 0.999999 6 = 0.99999
This is approximately 1 failure per 100,000 products. The introduction of a hinged latch on the sash prevents jamming of the latch (even with temperature movements of the sash relative to each other). The proposed technical solution makes it possible to increase the reliability of the SB flap opening system by approximately 100 times.

Claim

Solar battery of a spacecraft, consisting of a frame, a beam, upper and lower wings, interconnected in pairs by clamps and installed on the frame and beam, which are fixed to the body of the spacecraft using a pyro-device with a pawl rotating about the axis in a hole made in the body of the pyro-device , characterized in that a pyroelement is additionally installed in the body of the pyro-element, interacting with the pawl, and a spring-loaded latch is hinged on the lower flap, one end abuts against a bracket rigidly fixed to the upper flap, and the other interacts with the end of the latch.