Betaflight is an awesome flight controlling software for multi-rotor drones. Betaflight makes flying the drone more enjoyable and eases it. That’s why this software is so popular among the drone community. Even though it’s quite useful software, you might have to face some common issues while using this software.
Betaflight drone not arming issue is a most common issue when talking about common betaflight issues. Because there are so many people who use betaflight, they were able to find out why it’s happening and how to fix this issue. So in this article, I will explain why betaflight drone not arming and how to troubleshoot and fix them.
Why Betaflight drone not arming.
In most cases drone won’t arm when the drone model is not leveled, high CPU load, and the receiver channel glitches. Also, accelerometer and throttle related issues can cause preventing arming the drone.
Follow the below checklist to figure out which one causes your issue. Hopefully, you would be able to figure out the issue in your scenario and troubleshoot it. Before all that make sure to download the latest betaflight configurator and update the firmware.
Step 1: Check whether the Radio receiver is bound and working correctly.
The most common reason why drone not arming is the receiver is not setup correctly. Connect the drone to Betaflight and go to the receiver tab of the Betaflight configurator. (If you are having issues with connecting Betaflight read the Drone not Connecting Beaflight Article). Then whether channels are responding to stick movement in the correct order and direction.
Step 2: Check receiver channel mapping.
Go to the receiver tab of the Betaflight configurator and check whether each control on your radio is properly mapped to the flight controller. Ensure the corresponding bar on betaflight is moving when you move sticks on your radio. If it’s not check the below video to adjust the channel map.
Step 3: Check the minimum throttle value.
Usually, the drone won’t arm if its throttle value is too high. Therefore it calls the min_check parameter and checks it. It’s set to 1050 by default. To check the min_check value, go to the CLI tab and enter the “get min_check” function. Then you will be shown the min_check value on the screen. If it’s too low or high set it to 1050 by entering “set min_check 1050”. When you fully throttle down you must ensure the reported throttle value should be less than the min_check value.
Step 4: Check Accelerometer calibration.
The accelerometer is a safety feature built into Betaflight. Accelerometer sensors detect whether the drone is on a flat surface and if it is, allows the drone to arm. So it prevents drone arming if the drone is not approximately level. Therefore the drone won’t arm accidentally while carrying the drone. But if the accelerometer sensors are miscalibrated this feature would cause drone arming issues because the accelerometer can’t detect the surface it’s miscalibrated.
To check whether your drone is miscalibrated, open the Betaflight configurator and inspect the 3d drone model. If it’s not leveled your accelerometer requires a calibration.
Solution: Calibrate betaflight accelerometer.
- Connect the drone to the Betaflight configurator.
- Place the drone on a flat surface.
- Then click the “Calibrate Accelerometer” button to start calibration.
- Once you have done that, the 3d model would completely level in a few seconds.
Solution: Disable Accelerometer.
If you are unable to calibrate the accelerometer you can fix this issue by disabling the accelerometer feature. Go to system configuration and turn off the Accelerometer feature. Disabling the accelerometer feature would also reduce CPU usage so much but you are disabling a safety feature.
Solution: Change the small_angle parameter.
Setting the small_angle parameter to a custom value would allow the drone to arm within a custom angle range. Open the CLI tab of the Betaflight configurator and enter “get small_angle”. Then you will return the current small angle value. If you are not satisfied with that values enter “set small_angle ” and your custom value.
Step 5: Check Flight Modes.
In the modes tab of the Betaflight configurator, you can set up a spare channel for arming. You can set up it by 2 position switch. Once you set them you should save them. If it’s active and armed the box will turn yellow. Check your current flight mode is active and armed.
Step 6: Check CPU load.
If your CPU load on your flight controller is high, betaflight would prevent drone arming because the flight controller can’t do operations fast enough as an overloaded CPU. So you would have to reduce the CPU load of your flight controller to arm the drone. You can check the CPU load in the bottom status bar of the Betaflight configurator. Usually, the CPU load of the flight controller needs to be below 50%.
The common way to reduce CPU load is disabling unused, non-critical features like Softserial and LED_stip on the flight controller. Go to the “Configuration” tab and disable some features you don’t need. Also slowing down the PID loop frequency also would cause to reduce CPU load generously. Go to system configuration and set PID loop frequency to 4kHz or below but don’t go below 1kHz. If the above things didn’t help with reducing CPU load, it would be good if you can upgrade the flight controller to F4 or F7 MCU.
Step 7: Check the Moron threshold.
Some flight controllers have more sensitive gyro and the drone would reduce to initialize after power up which leads to drone arming issues. Increasing the Moron Threshold value is the best way to reduce gyro sensitivity while initialization. Set the moron threshold value of Betafligh CLI to 100 – 120 to reduce gyro sensitivity.
