Bright Sword starts with the grenade flat.

Chapter 381 Compound Bow vs. Traditional Bow
Therefore, since he had the conditions, Liu Xiu would naturally give his child Liu Siyue the best bow and arrow.

After all, Liu Siyue is now the eldest sister of those children!
The pulley compound bow is the culmination of modern mechanical science. Although it still relies on manpower, in actual use its power is even not inferior to that of high-powered firearms.

Of course, the main reason why Liu Xiu wanted to make such a pulley compound bow with modern machinery and modern industry for his daughter Liu Siyue was that he hoped to use the power of the modern compound bow to open up trade with the Na'vi people.

That's right, according to Liu Xiu's enemy and friend map, the Wandering Blue Star has come within one light year of Pandora after more than ten years of sailing. When the Wandering Blue Star gets closer, Liu Xiu plans to return to the Wandering Blue Star and prepare to fight against the immigration fleet of Blue Star No. 2.

After all, Liu Xiu had detected the space jumping ability and found out that the second expedition fleet from Blue Planet No. 2 had already set off and was expected to arrive in another five years, so there was not much time left for Liu Xiu to prepare.

Of course, the reason why Liu Xiu wanted to promote modern compound bows among the Na'vi people was mainly because he was afraid that the Na'vi people were not used to using firearms or that they were afraid that the Na'vi people would have a resistance to hot weapons.

Besides, considering that almost all Na'vi are excellent archers, the reworked bow is the Na'vi's favorite.

And in a certain sci-fi movie, isn't there a guy using a bow and arrow? Moreover, a modern compound bow with explosive arrows and the strength of the Na'vi people is actually not much weaker than modern firearms.

Of course, the main reason why modern pulley compound bows beat traditional bows is that the principle of pulleys and levers is applied to the bow! Rather than just relying on composite materials to increase the power of the bow, this is a structural change in the bow.

You should know that the structure of the eccentric wheel of the pulley compound bow is similar to a pulley. It consists of a small wheel and a large wheel with a rope between the small wheel and the large wheel. When the bowstring is pulled, the string will be wound around the large wheel and rotate through the bearing on the small wheel. At the same time, the distance between the center of the small wheel and the center of the large wheel is different, which creates eccentricity.

Secondly, the main principle of the compound bow eccentric is to use the lever principle in physics. When we pull the bowstring, the tension of the string not only acts on the arrow, but also on the eccentric, pulling it to rotate. As the string is pulled to the maximum, the eccentric also rotates to the maximum position. At this time, the tension of the arrow reaches the maximum and gains additional elastic force. It is this elastic force that makes the arrow shoot faster and more powerful.

Finally, the eccentric wheel of the compound bow has another important function, which is to reduce the recoil. When we shoot, the arrow will produce a reaction force after leaving the string, which is the recoil. The eccentric wheel of the compound bow reduces the recoil by reducing the force of the arrow rebounding after leaving the string when the string is fully pulled. This makes it easier for the archer to control the direction of the arrow and improves shooting accuracy.

It is precisely because of the use of this pulley and the eccentric wheel's lever that the pulley compound bow can be used to the extreme in terms of labor saving.

When Liu Siyue came to find Liu Xiu, Liu Xiu had already finished making Liu Siyue's compound bow in the machining cabin. However, when Liu Siyue saw the bow made by Liu Xiu, she said with an unhappy face:

"Dad, is this a bow you made? Why is it different from the bow Uncle Jack uses? Why does this bow have two big wheels on it?"

After hearing Liu Siyue's question, Liu Xiu smiled and said:
"That's because the bow your dad made this way is more powerful and can shoot farther and more accurately! If you don't believe me, let's go outside and let dad demonstrate it to you!"

After saying that, Liu Xiu took a few aluminum metal arrows he had just made and went to the deep forest outside the spacecraft!
Liu Xiu spent a lot of money to make the modern bow in his hand.

Take the bowstring of a compound bow for example. You have to know that because the pulling force of a compound bow is very large and the bowstring rebounds quickly, the bowstring is often prone to breakage.

In order to make the bowstring strong, Liu Xiu directly used carbon nanotube material as the bowstring.

You should know that carbon nanotubes are the materials used when building space elevators.

So the bowstring made of carbon nanotubes is not only strong in tension, but also has no need to worry about the bowstring breaking. And because the compound bow uses the principle of pulley, it is very easy to shoot accurately in seconds.

For example, the compound bow in Liu Xiu's hand has a pulling force of 100 kilograms. After it is fully pulled open, only 70% of the force required to maintain it is needed.

In other words, as long as you can pull it open in one breath, you only need to use 30 kilograms of force to maintain it after pulling it open.

After Liu Xiu drew the bow and arrow, he just aimed slightly and then let go. The metal arrow in his hand flew thirty meters and accurately pierced through a tree trunk that was thicker than his waist.

After shooting, Liu Xiu was quite satisfied with the power of the compound bow he made. Then Liu Xiu lowered his head and smiled at the stunned Liu Siyue:

"How is it? My bow is pretty powerful, isn't it? It's more powerful than the bow and arrow in your Uncle Jack's hand!"

Liu Siyue nodded immediately and said:
"Dad, your bow and arrow is much more powerful than the one in Uncle Jack's hand. Let me try it!"

But Liu Siyue is still only a ten-year-old child after all, so even though she inherited the enhanced genes of Liu Xiu and Qin Huairu, she can still pull 100 kilograms at the age of ten.

So when Liu Siyue took the bow from Liu Xiu, she couldn't hold on until the bow was fully drawn.

Fortunately, the tension of the composite pulley bow designed by Liu Xiu can be adjusted at will.

Of course, when the pulling force was adjusted to 60 kilograms, Liu Siyue was finally able to pull it open and shoot.

Of course, with a pulling force of 60 kilograms, even though the arrow was made of tungsten steel arrowhead by Liu Xiu, it still failed to penetrate the uncle that Liu Xiu had just shot.

However, Liu Siyue was very satisfied with the arrow that had already penetrated more than ten centimeters into the wood, so she immediately grabbed the remaining arrow in her hand and said to Liu Xiu with a smile:
"Dad, I'll go find the spiders then. They're having fun! I heard Uncle Jack is going to teach us how to hunt and shoot prey today!"

Liu Xiu did not object to Liu Siyue's going, but said seriously:
"Siyue, you must remember not to aim your arrow at Jack or your playmates! You have seen the power of this bow!"

Liu Siyue nodded obediently to show that she understood. However, after Liu Siyue left, Liu Xiu felt that the bow was still too weak to use. After all, Liu Xiu's physical fitness was twice that of an ordinary person!

Therefore, Liu Xiu felt that a bow weighing one hundred kilograms was still somewhat unsuitable for his current condition, and with the martial arts that Liu Xiu had practiced, he had no problem pulling a bow weighing three or four hundred kilograms.

So after seeing Liu Siyue off, Liu Xiu returned to the CNC machining center and started making bows again.

(End of this chapter)