How to design a UAV to realize eight-character flight mode

Beginners' guide to APM began to be enchanted in 2009, and from the electricity in 2009 to the four-axis play in 65438+February this year, I taught myself solo all the way. The biggest problem with getting started solo is that you are always confused about the model at first and don't know where to start. Although the forum has many senior posts and teaching materials. But in my feeling, even if I read it, I still have a little knowledge most of the time, and I can't solve the most practical problem, that is, I will fly first. As a result, many model airplane friends bought equipment and materials, but they have been fooling around and quit because they failed to experience the fun of flying. I post this post only by combining my experience of flying at least four axes from APM novice to now, and I know exactly what knowledge the novice actually wants to know, not all knowledge, so that the novice can fly four axes in the shortest time and experience happiness. After that, with experience, novices can naturally understand other posts of their predecessors, step by step from novices to experts. Let's get down to business step by step. Novices can basically fly four axes as long as they follow my steps. When I first arrived at APM, I was always worried about how to ensure safe take-off and flight. To sum up here, it is mainly in five aspects: 1 is the installation of flight control and GPS, the wiring of flight control, the installation of computer terminal ground station, the update of flight control firmware, and the calibration of flight control compass and accelerometer. 5 is remote control rudder quantity correction and flight mode setting. Basically do the above parts, you can take them off, and what is mentioned in other posts or documents can be ignored for the time being. First of all, the installation and wiring assembly of APM is always the first step. Although the assembly of four-axis racks is also very important, basically, rack assembly merchants also have a copy of materials, and various racks are different, so I won't talk about it here. Only the installation of APM is mentioned here. 1, APM installation The APM flight controllers purchased now basically have housings, and there is an arrow pointing forward in English on the housing, indicating that the pointing arrow is aimed at the nose direction. Then stick the flight control on the center of gravity of the frame with double-sided tape (Figure 1) (PS. Regardless of the shock absorption problem). Then install GPS, APM2.6 because the compass is placed outside the GPS shell, the installation position of GPS should also be considered. Just aim the exit position of GPS at the tail (Figure 2). 2.APM wiring, let's talk about GPS wiring first, as shown in figure (Figure 3). APM flight control has two connections, input and output (input and output). Input terminals are used to connect receivers as long as simple channels 1 pairs of channels 1, 2 pairs of 2, 3 pairs of 3, 4 pairs of 4, 5 pairs of 5 and 7 pairs of 7 (Figure 4). Note that the direction of line insertion is the innermost position of signal line and the outermost position of ground line (black line). The output terminal is used to connect the electric adjustment, because the four-axis mode is different (X4 or +4), and the connection mode of the electric adjustment is also different. Here, we only discuss the wiring in X4 mode (Figure 5). The X4 mode has the nose in front, and the 1 motor in the right front is connected to the 1 socket in APM output, the No.2 motor in the left rear, the No.3 motor in the left front and the No.4 motor in the right rear. One and two are forward paddles (Figure 6), and three and four are reverse paddles (Figure 7). Second, the installation of the ground station The computer-side ground station is MISSIONPLANNER, and the latest version is 1.2.90. This can be done in many places, but I don't know if it can be Baidu. Then install APM driver, I don't know if it's Baidu. After the installation is completed, you can connect APM and computer directly with USB, and then select COM port and rate in the upper right corner of MP (Figure 8). Generally, as long as the driver is installed, click on the COM port and you will see which COM port should be selected. If it's still unclear, go to the device manager to check. The rates are all 1 15200. 3. Do not click the link to update the APM firmware. Select the first option, INSTALLFIRMWARE, on the initial setup page (Figure 9). The page on the right will automatically update the latest firmware, and then click X4 firmware to update it. When the update is complete, click CONNECT, so that the APM and the computer are connected. Four. Calibration of APM compass and accelerometer 1. Compass calibration (figure 10) is the second option in the second option of the initial setup page, and APM2.6 is the external compass, as shown in the page figure 1 1 on the right. Then click on the field calibration. Please see the video for the calibration method (thanks to the foreigners and students who put the video on Youku). You don't have to keep turning like a foreigner in the video, you can turn in the opposite direction. Check whether the compass is calibrated accurately. Check the upper left corner, as shown in figure 12 in FLIGHTDATA. If the nose is facing north, check that it is aligned with N on the scale. If there is no problem, the compass has been calibrated, otherwise, recalibrate. 2. Accelerometer Calibration Select the third of the second options on the initial setup page, acceleration calibration (Figure 13), and then click Calibrate Accelerometer on the right page. Accelerometer calibration is relatively simple, and no video is needed. Check whether the accelerometer is calibrated accurately. Check 438+02 in Figure 65402 to see if the horizontal line is balanced when the rack is placed horizontally. Otherwise recalibrate. 5. Remote rudder calibration and flight mode setting 1. Remote rudder calibration On the initial setting page, select the fourth option of the second option, Radio Calibration (Figure 14), click Calibration, then move all the rocker and switches in the remote control to the end, and then select End. Remember that the pitch lever is in the opposite direction to the display. If not, please set the reverse direction on the remote control. 2. Set the flight mode on the initial setup page. Select the fifth option of the second option, FLIGHTMODES (figure 15). Select the three-stage switch for channel 5 on the remote control. Turn the three-stage switch, and you will see the mode jump on the right page. Then try to turn off the control and see if the mode will automatically jump. If yes, choose the one that jumps as RTL, so that an out-of-control automatic RTL can be realized. If not, then consider it another way. Then three modes are selected for the three-stage switch, and generally four modes are needed, namely, stable self-stable mode, altitude setting mode, standby fixed-point mode and RTL return mode. Different remote controllers are not described here because of the different settings of the six-level switch.