Coreless cup four-axis traversing machine

This project is stitched together with reference to the following two projects:

https://oshwhub.com/PQG2030PQG/kai-yuan-si-zhou-fei-xing-qi

https://oshwhub.com/caisheng/naze32-fei-kong-ban

Updated version 2.0:

Fixed problem 1: Download firmware via serial port. The reason why the firmware could not be downloaded before was because the chip needed to be reset when the BOOT0 jumper was shorted to 1. Therefore, I exposed the RST pad next to C7 and used it to pull down to reset the STM chip. This way Use the onboard TYPEC port to download the firmware directly through the serial port, and directly touch the RST and GND pads with Dupont wires.

Fixed problem 2: WS2812 lamp beads could not be used before because I connected the wrong IO port. It has been corrected now.

Updated function 1: Lead out TX2. Originally, only RX2 was led out (used to connect single-wire protocols such as SBUS or IBUS), but there are many receivers such as ELRS that need to use RX and TX, so I also led out TX2. But if all the components are welded, RX2 is still in SBUS mode. Because there is an S8050 inverter, if SBUS is not needed, there is no need to weld R18 R17 Q6. You only need to short-circuit the lines marked between R17 and Q6, and leave R18 empty. The pad under the purple line is where the tin short circuit is required when using a non-SBUS receiver.

I just started flying quadcopters, and I happened to have two idle Fuse receivers on hand, so I was thinking about which aircraft to put them on for fun.

Then I found a great coreless four-axis in the square (a project of Cool Electronics Player), but it couldn’t be connected to an external receiver and needed to make a remote control. The parameters needed to be adjusted by entering the source code.

It is not suitable for a player who has a special remote control for model aircraft. Then there is the parameter adjustment. I previously drew an F1 mini flight control board based on the principle of NAZE32 (refer to Cai Zi’s project and video explanation). The board has a gyroscope, barometer, and black box, but there is no OSD or galvanometer. After all, it is an F103C8T6, an old thing in the flight control that has long been outdated. It is still good for visual inspection of the flying hollow cup.

Finally, we have this project, which uses NAZE32 firmware, an external PPM/SBUS/IBUS receiver, and uses CF or CF software to adjust the parameters of the coreless four-axis. The USB debugging interface uses TYPEC, and the battery uses a 1S format battery.

When welding, it is recommended to apply solder paste and heat it with a teppanyaki (a heating plate that costs 10 yuan on a certain treasure). It only takes a few minutes. The direct plug is soldered last. If you want WS2812 on the bottom, you can only solder the top surface first. Then use a soldering iron to solder WS2812.

B station video demonstration and parameter adjustment

Firmware burning: I use STLINK. If it is a serial port download, you need to short BOOT0 to 1, and then use a Dupont wire to short the RST pad and GND pad next to C7. In the attachment, I have uploaded the NAZE32 firmware of CF and BF. The most fascinating thing is that the flashed BF firmware can be used to adjust parameters with CF. It is recommended to use the BF version of the firmware and use BF parameter adjustment. You can use STM32CUBEprogrammer to burn firmware. If there is no STLINK but JLINK and DAPLINK, you can use KEIL5 to directly burn the HEX file (specifically, Baidu will not explain it here).

The interface for SWD programming is as follows, just cut off one end of the Dupont wire and solder it on.

After STLINK is plugged in, click connect in the upper right corner and then open the firmware. Click Download to start burning.

The remote control I use is Fossil I6X, and the receiver is equipped with RX2Apro. This receiver can only output IBUS and PPM. Because I connected SBUS in reverse phase, I don't use IBUS, only PPM.

Physical map:

I have marked the rotation of the motor with silk screen on the new version of the PCB. For the installation of the propeller, please see my photo below.

To put it simply, the wind has to blow downward, otherwise it won’t be able to fly. The motor rotation can be reversed by exchanging the two wiring connections of the motor.

If the propeller is marked AB, you can install it according to my method. If it is not marked, just look at the circled part. The high position of the propeller can be the same.

Takeoff pictures:

Battery instructions:

The battery I used is a 1S battery (4.35V), which is a bit expensive at 19 yuan. The charger only costs a few yuan to buy a 4.35V charging module, and then buy a PH2.0 plug to make a high-voltage charger. Don’t buy the matching 1S battery charger. It charges very slowly. It’s most cost-effective to buy a high-current lithium battery charging module and modify it yourself, and it charges quickly. I only use a 4.35V 3A charging module for this battery. It can be fully charged in a few minutes, and the battery can fly for four to five minutes. If you buy two more batteries, you can have unlimited refills. It is recommended to use a 4.35V high-voltage battery to increase the lift of the aircraft.

You can also use a 4.2V battery. The entire TP4056 can be charged, but you must pay attention to the C number of the battery. My 1S battery is 70C, and the maximum discharge can reach almost 20A. The coreless cup will definitely not use that much.

I bought a smaller motor and propeller. I used a 716 motor and a 46mm propeller. It is recommended to use a 720 motor and a 55mm propeller. I have not tried the 8520 motor, but it is clear that the 75mm propeller is too big. I originally wanted to bring a 1300MAH lithium battery, but found that it couldn't fly. I might just use 8520 and 75MM propellers. Although the motor and propellers were chosen wrongly, the power is pretty good compared to the coreless plane I bought from Xianyu. It can take off at 50% throttle, while the plane bought by Xianyu needs 80% throttle to fly.

A fish-residue hollow-cup aircraft (615 motor + 36mm 4-blade propeller?)

When I tested my hollow cup later, the hot melt glue melted. I didn't use high-temperature hot melt glue, so. . . Tie the motor with a rubber band

Flight control parameter adjustment:

If you are a veteran of flying airplanes, the main thing is to change the ESC protocol to brushed, and then configure the unlock button. You can also watch the B-site videos I uploaded.

If you are a novice, just import my BF flight control configuration file directly.

Methods as below:

             First download the BetaFlight parameter adjustment software, which is available on GITHUB. Du Niang link (click to open the link → ): Extraction code: tqsz

             Open the software, click the restore button, and then select the path to my configuration file.

             Wait for the message in the upper left corner that the recovery is successful, then level the aircraft, click to reset the Z-axis, and then click to calibrate the accelerometer.

The receiver used in my flight control profile is PPM. Channel 5 AUX1 is the motor unlocking channel, and channel 7 AUX3 is the flight mode selection (default auto-stabilization, mid-position semi-autonomous, and high-position manual). Therefore, channel 7 AUX3 needs to use three segment switch. The assignment of channels and remote control switches must be set according to your remote control. You can change the receiver to IBUS or SBUS after importing, but the inverter of SBUS may be redundant, so it is recommended not to solder the inverter part first, and then test. If it doesn't work, then solder the inverter and then connect to SBUS. IBUS does not need to solder the inverter

The inverter part is R18, Q6, R17. When not soldering, you need to short-circuit the connecting parts of R17 and Q6 with tin. R18 is not soldered.

V1.1 version

V1.0 and V1.1

V1.1

Mainly to test the functions of WS2812 and buzzer (the buzzer cannot be used)

Lighting description: The direction of the pink lamp bead is towards the machine head. It displays pink when it is not unlocked and blue when the motor is unlocked.

                 Green represents the battery level. It is green when fully charged and red when there is a low voltage warning. In between, it is a gradient color, such as yellow or orange.

                 You can also set the lighting function yourself in the BF parameter assistant software, and the parameter configuration file will also update the lighting.

Untested functions: The SBUS function has not been tested. The RX2Apro and FLi14+ I have cannot seem to output SBUS. The IA10B can output SBUS but it is too large, and I installed it on an F330 aircraft.

Possible problems: I don’t know if the SBUS inverter is redundant. If the SBUS output from the receiver is already inverted, then the negative will be the positive. SBUS is an inverse logic level. It is recommended to use PPM. Can save a triode.

Known issues: The motor base of the 716/720 motor cannot really fit into the fixing hole. It feels like it is specially used for the 8520 motor. If you use sandpaper, you have to grind off at least half of the thickness of the 3D printed motor base. Currently, it is heated Fixed with melt glue. The battery and receiver are fixed with rubber bands (because I don't know how to design these fixing holes at the moment, I just use the fixing holes of the original PCB). It is not impossible to fix it with hot melt glue, but it is recommended to use high-temperature hot melt glue above 100°. The hollow cup is still quite hot after running for a long time. It feels like 60 or 70 degrees. Ordinary hot melt glue will soften immediately.

                    There was no response during the BEEPER function test. I tried both active and passive devices, and the IO port was not connected correctly. It’s very strange. Maybe the driver method is wrong?

                    The barometer BMP280 does not need to be welded because the height error is too large. It is enough to only weld the gyroscope MPU6050.

Possible subsequent upgrade options:

This rack may not be used because the fixation of the motor and battery is really awkward. I may remove the motor fixing holes and use the QX110 or Q100 or 8520 coreless cup racks on Taobao.

After all, it is much easier to fix the motor and battery this way. Maybe it can also install a 25mw small image transmission. At present, the flight controllers of this type of coreless cup are all F3, which do not have OSD function, so I think there is no difference if it is replaced by F1. The 25MW image transmission is just a picture.