Start with the more familiar magnet: In principle, the upper and lower magnets are opposite to each other, as long as the direction of the magnetic field is in line with the geometric center of gravity of the magnet above, and the magnetic force is equal to the gravity of the magnet above. It is a point where the above magnet can be suspended in the air. But operating, this is almost impossible. For if the ordinary magnet deviates slightly from the equilibrium position, the change of force will cause it to deviate more from the balance than to go back, just like a needle on the table. Those who have played magnets in childhood should be familiar with this phenomenon.
In fact, the suspension device is a very complex closed-loop feedback servo system. In addition to the electromagnet as the actuator, it must have sensors and feedback amplification control circuits. Around the electromagnet there are four metal rods wound around the coil.
Here's how it works: If the floating globe deviates from a fixed position due to any disturbance, the sensor will automatically measure the size of the change. After magnifying this error, the appropriate algorithm(this is the key) becomes the execution control signal to correct the magnetic field size and even direction of the electromagnet(by changing the magnetic field size of the four electromagnets, they can synthesize magnetic fields in different directions). Compensation to make it opposite The direction of motion returns to the equilibrium position so that it can be steadily suspended in a fixed position. This correction process is very fast and very sensitive, so it seems that the globe is very stable and does not shake. Therefore, the circuit of this system is relatively sophisticated and must always be energized to work.
Principle introduced, details can refer to the picture.
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It's mainly a magnetic levitation device. Next analysis of the suspended globe.
1. Electromagnetic fields and magnet magnetic fields provide buoyancy ratios.
How much buoyancy, as mentioned above, can be generated by magnets that provide buoyancy and by four coil rods? Almost 100 % of the force is a magnet product, and the rod only produces a correction to maintain its balance. So this product is very power-saving, a month of electricity consumption less than one degree.
So, can you increase the buoyancy of the electromagnetic field to reduce the amount of magnets? The answer is yes. In fact, most magnetic levitation scientific research institutions use a large proportion of electromagnetic energy. But as a maglev globe, this does not work. The process of converting electrical energy into magnetic force will produce a relatively large energy loss. As a long-working ornamental product, if a large proportion of electromagnetic energy is used, the suspended globe will become an electric Tiger, followed by: excessive current, It will also greatly reduce the life of the product. This is also a major disadvantage of pirated goods. Low cost and poor quality.
2. Power supply for suspended globe -- an appropriate algorithm
At present, almost all suspended Globes are powered by 220 V household power.
Can you power it with a battery or USB?
can
Go back to the above Quot; Appropriate algorithm & amp; Quot; As long as the algorithm is fine enough, it requires only a small amount of electricity to make the system work. This &; Quot; Algorithm &; Quot; This is the key technology of magnetic levitation globe. At present, the highest level of suspended globe technology in Shenzhen general astronomy technology and Shenzhen Hengyi technology. We can purchase 2 M-diameter suspension globe, Hengyi small-size precision suspension device, also up to battery or USB power level. But still that problem, magnetic levitation globe as an ornamental product, the appearance of the most important, put in a battery box will occupy a lot of space, in which case, have to increase the base size, seriously affect the beauty. There is no battery version of the suspension device until now. USB power supply is also to use USB cable, and the home 220 V power supply similar. The practical significance is also not great.
This &; Quot; Appropriate and Algorithm & Quot; There is no more explanation here. .. .. ) Because it is so difficult to understand, it can not only make the globe float smoothly in the air, but also enable the globe to rotate. It is not difficult to understand the rotation. The four magnetic rods can be easily realized by changing the size of the magnetic force, but they can be turned clockwise and counterclockwise. .. .. I don't understand why. ..
The accuracy of this algorithm also directly determines the product life and rotation stability. Some Globes rotate smoothly while others shake their heads. There are many online video, you can look at when you are free.