Li Tangshan was carrying out calculations such as the center of gravity in MATHLAB, and a series of calculations wasted Li Tangshan's time all day. On the apron outside the window, Cao Yan from Kazakhstan's military industry, Hong Tiejun from the National Defense Science and Technology University, and Huang Fuxing from the Chinese Academy of Sciences have completed the assembly and have begun to fly and debug the aircraft. Li Tangshan doesn't even have the butt of a drone here, and everything is still at a theoretical level. Slowly began to get anxious in his heart, and Li Tangshan also began to worry about himself, thinking: "I won't be eliminated in the first round, I'm too sorry for those old-timers."

Li Tangshan also found that he was bored and couldn't do his work, so he secretly kept cheering himself up, and he tried to use himself to calm down: "There is no way to kill me in the jungle, isn't it just a drone, can it still stump my young master of the Li family." Li Tangshan, come on! ”。

At this time, the low-altitude roar of the drone outside the window, and the pleasant sound of the propeller cutting the wind made Li Tangshan unable to calm down at all, Li Tangshan tried to calm down with the mental method that Uncle Zhuo usually taught him, but the mental method can make people quiet, but there is no way to really do things.

The sky outside the window is slowly darkening, Cao Yan, a military engineer of Kazakhstan, Hong Tiejun of the National Defense Science and Technology University, and Huang Fuxing of the Chinese Academy of Sciences have completed the adjustment, and they can quietly wait for the actual combat competition in the afternoon of the day after tomorrow. Li Tangshan sighed that people are better than others, and they are really sad.

Without interference outside the window, Li Tangshan finally quieted down. You can assemble the rack by hand, let's get the quadrotor first, and the quadrotor is equal to half the success. Li Tangshan originally played with quadcopter with his drone classmates, but when it came time to assemble a quadcopter drone by himself, he didn't know what to do? Li Tangshan could only temporarily cram, and according to the four-rotor assembly textbook that he checked on the Internet.

How to connect the three wires of the brushless motor?

Where should the ESC be installed?

How should the ESC power supply and control signals be connected?

What is this row of Dupont wires?

Li Tangshan followed the tutorial and learned little by little.

"LED light cables, GPS cables... "The battery is done with the XT60 interface", "Pay attention to the position and direction of rotation of each motor, all right", Li Tangshan said while checking the data and wiring.

After a few hours, a quadcopter fixed-wing aircraft was finally assembled.

Li Tangshan doubled it twice, "It looks like that, there should be no problem in theory, let's test it with power," Li Tangshan said to himself.

Li Tangshan picked up the remote control and shook the joystick of the remote control. The plane did not reflect at all, and Li Tangshan carefully checked it again, and it turned out that the communication code channel was set to 25 on one and 255 on the other. The two communication channels were inconsistent, and the aircraft could not receive commands from the remote controller.

Li Tangshan quickly flipped the code setting, and this small problem was not difficult for this high-achieving student majoring in communications. Li Tangshan carefully checked and checked that the position of the motor and the direction of rotation are correct in all directions?

After passing a series of tests, Li Tangshan himself felt that he should be 80% sure that the plane could fly. Li Tangshan, based on what he had learned before, should add a forward power to the front. The magical quadcopter plus fixed-wing aircraft, this composite fixed-wing vertical take-off and landing UAV was born in the hands of Li Tangshan.

Digression: Multi-rotor is an aerial camera that everyone often sees, and photography enthusiasts use it for aerial photography. Fixed-wing fighters are seen in general, and helicopters are single-rotor. Friends who are interested in drones can ask Youku to find Mark Li's tutorial on drone training to understand the classification of drones.

Li Tangshan thought for a long time, how should he give this plane a thrust?

Li Tangshan referred to some aerodynamic materials of fixed-wing aircraft, and felt that a forward power system should be added in the front, and the composite fixed-wing aircraft should achieve the effect of vertical take-off and landing UAVs. Li Tangshan is familiar with fixed-wing vehicles, and he has done a good job of powerplant in three or two clicks.

Li Tangshan looked up at the window, and the sky had already begun to dawn.

"That's it, test the flight." Li Tangshan said happily.

After a night of assembly, Li Tangshan finally got the plane out of the plane, although it didn't look very good. Li Tangshan pushed the plane to the outdoor power strip.

"Then let's test it with electricity first," Li Tangshan said to himself.

After Li Tangshan turned on the backup power supply of the aircraft, the aircraft behaved normally, and the spiral wings could move. Double-check, there are no problems in all aspects.

Li Tangshan was full of confidence, waiting for this small plane to soar into the sky, and casually appreciate the results of his day.

Li Tangshan picked up the controller and looked at the data transmitted back from the ground, and the aircraft indicator light kept flashing red.

Suddenly, there was a beep, and the plane's indicator light turned green. Li Tangshan looked at the ground data showing that there are 12 GPS satellites, which are already ready to take off. Li Tangshan set the route, and everything was ready. Li Tangshan clicked the button to take off on the screen, heard the buzzing sound of cutting the wind, the plane increased the throttle for itself, the plane did not do as imagined, so he doubled the throttle, the plane finally had to leave the ground, and then gave some throttle, the plane immediately had a power imbalance, and the flight immediately rolled backwards for a few weeks. Li Tangshan hurriedly retracted the accelerator, but it was still too late, and the plane rack had already smashed on the concrete floor and broken into several pieces. This is the end of the night's work.

"It's going to be fried so soon, what about tomorrow afternoon's game?" Li Tangshan was very helpless.

"Dead horses as live horse doctors" time is too tight to continue Li Tangshan is annoyed, Li Tangshan moved the rack back to the room after the explosion, and soon found out what caused it. It turns out that the fixed-wing and multi-rotor power act at the same time, resulting in excessive thrust on one side and resulting in a rollover.

Li Tangshan reused the spare rack and started to replace the broken rack again. At this time, there was a roar outside the guest. Xie Shiliu's plane from Tsinghua University also flew, and it seemed that Xie Shiliu's plane was still very successful and smooth. Li Tangshan's plane, which was left of the five people, had not yet flown off, and the others had tools for the competition, so Li Tangshan could only speed up.

Li Tangshan spent another day and a night, and Li Tangshan reassembled the plane, adjusted the original code, and made sure that there was no problem communicating with the ground station. After two consecutive days of uninterrupted study and work, Li Tangshan slept no more than 4 hours a day, and such high-intensity work made Li Tangshan feel tired and weak.

Li Tangshan was not very relieved, so he tested it again by powering it on, and this time the data of the plane in all aspects was finally normal.

There were only a few hours left before the competition, and Li Tangshan still pushed the plane out to test the situation of the plane on the spot, and this time Li Tangshan's re-debugging of the aircraft performed well.