자동 튜닝은 안정적이고 반응성은 높은 비행에 탁월한 컨트롤러인 PX4의 속도와 자세를 자동으로 튜닝합니다(다른 튜닝은 "선택 사항"에 가깝습니다).
Tuning only needs to be done once, and is recommended unless you're using a vehicle that has already been tuned by the manufacturer (and not modified since).
WARNING
Auto-tuning is performed while flying. The airframe must fly well enough to handle moderate disturbances, and should be closely attended:
- Test that your vehicle is stable enough for autotuning.
- Be ready to abort the autotuning process. You can do this by changing flight modes.
- Verify that the vehicle flies well after tuning.
사전 튜닝 테스트
The vehicle must be able to fly and adequately stabilize itself before running auto-tune. This test ensures that the vehicle can fly safely in position controlled modes.
To make sure the vehicle is stable enough for auto-tuning:
비행 구역이 깨끗하고 공간이 충분한 지 확인하기 위하여, 일반적인 비행 전 안전 점검을 실시합니다.
Take off and .
Use the RC transmitter roll stick to perform the following maneuver, tilting the vehicle just a few degrees: roll left > roll right > center (The whole maneuver should take about 3 seconds). 기체는 2번의 진동 이내에서 안정화되어야 합니다.
각각의 시도에서 더 큰 진폭으로 기울이면서 기동을 반복합니다. 기체가 ~20도에서 2번의 진동 내에서 안정화될 수 있으면 다음 단계로 이동합니다.
피치 축에서 동일한 동작을 반복합니다. As above, start with small angles and confirm that the vehicle can stabilise itself within 2 oscillations before increasing the tilt.
If the drone can stabilize itself within 2 oscillations it is ready for the auto-tuning procedure.
WARNING
If the drone cannot stabilize itself sufficiently, follow the instructions in the troubleshooting section. These explain the minimal manual tuning to prepare the vehicle for auto-tuning.
Auto-tuning Procedure
The auto-tuning sequence must be performed in a safe flight zone, with enough space. It takes about 40 seconds (between 19 and 68 seconds). For best results, we recommend running the test in calm weather conditions.
The recommended mode for autotuning is , but any other flight mode can be used. The RC sticks cannot be used during autotuning (moving the sticks will stop the autotune operation).
The test steps are:
Perform the pre-tuning test.
Takeoff using RC control
Enable autotune.
In QGroundControl, open the menu Vehicle setup > PID Tuning:
Select either the Rate Controller or Attitude Controller tabs.
Ensure that the Autotune enabled button is enabled (this will display the Autotune button and remove the manual tuning selectors).
Read the warning popup and click on OK to start tuning.
드론은 먼저 빠른 롤 동작을 수행한 후 피치 및 요 동작을 수행합니다. The progress is shown in the progress bar, next to the Autotune button.
WARNING
If any strong oscillations occur, land immediately and follow the instructions in the Troubleshooting section below.
Additional notes:
- Whether tuning is applied while flying or after landing can be configured using parameters.
문제 해결
Drone oscillates when performing the pre-tuning test
자동 튜닝 실패
If the drone was not moving enough during auto-tuning, the system identification algorithm might have issues to find the correct coefficients.
Increase the parameter by steps of 1 and trigger the auto-tune again.
드론이 자동 튜닝 후 진동합니다.
Due to effects not included in the mathematical model such as delays, saturation, slew-rate, airframe flexibility, the loop gain can be too high. To fix this, follow the same steps described when the drone oscillates in the pre-tuning test.
여전히 정상 작동하지 않는 경우:
Attempt manual tuning using the guides listed in See also below.
Optional Configuration
Apply Tuning when In-Air/Landed
0: the gains are not applied. 자동 튜닝의 결과를 직접적으로 사용하지 않은 체로 검사하는 경우에 사용합니다.1: apply the gains after disarm (default for multirotors). 이후, 조종자는 주의하여 이륙하면서 튜닝 결과를 테스트할 수 있습니다.2: apply immediately (default for fixed-wings). 새로운 튜닝이 적용되고, 교란이 컨트롤러로 전송된 후, 다음 4초 동안 안정성이 모니터링됩니다. 제어 루프가 불안정한 경우, 제어 게인을 즉시 이전 값으로 복원합니다. 테스트를 통과하면, 조종자는 새로운 튜닝 결과를 사용할 수 있습니다.
개발자 SDK
Autotuning is started using MAV_CMD_DO_AUTOTUNE_ENABLE MAVLink command.
At time of writing the message is resent at regular intervals to poll PX4 for progress: the COMMAND_ACK includes result that the operation is in progress, and also the progress as a percentage. The operation completes when the progress is 100% or the vehicle lands and disarms.
INFO
This is not a MAVLink-compliant implementation of a command protocol long running command. PX4 should stream progress as the protocol does not allow polling.
The feature is not yet supported by MAVSDK.
배경 및 세부 사항
PX4 uses PID controllers (rate, attitude, velocity, and position) to calculate the outputs required to move a vehicle from its current estimated state to match a desired setpoint. The controllers must be well tuned in order to get the best performance out of a vehicle. In particular, a poorly tuned rate controller results in less stable flight in all modes, and takes longer to recover from disturbances.
Generally if you use a frame configuration that is similar to your vehicle then the vehicle will be able to fly. However unless the configuration precisely matches your hardware you should tune the rate and attitude controllers. Tuning the velocity and position controllers is less important because they are less affected by vehicle dynamics, and the default tuning configuration for a similar airframe is often sufficient.
Autotuning provides an automatic mechanism to tune the rate and attitude controllers. It can be used to tune fixed-wing and multicopter vehicles, and VTOL vehicles when flying as a multicopter or as a fixed-wing (transition between modes must be manually tuned). In theory it should work for other vehicle types that have a rate controller, but currently only the above types are supported.
Automatic tuning works well for the multicopter and fixed-wing vehicle configurations supported by PX4, provided the frame is not too flexible (see below for more information).
The vehicle must be flying in an altitude-stabilized mode (such as Altitude mode, Hold mode, or Position mode). The flight stack will apply a small disturbance to the vehicle in each axis and then attempt to calculate the new tuning parameters. For fixed-wing vehicles the new tuning is applied in-air by default, after which the vehicle tests the new settings and reverts the tuning if the controllers are not stable. For multicopter, the vehicle lands and applies the new tuning parameters after disarming; the pilot is expected to then take off carefully and test the tuning.
The tuning process takes about 40 seconds (between 19 and 70 seconds). The default behaviour can be configured using parameters.
자주 묻는 질문
어떤 기체 유형이 지원됩니까?
Autotuning is enabled for multicopter, fixed-wing, and hybrid VTOL fixed-wing vehicles.
While it is not yet enabled for other frame types, in theory it an be used with any frame that uses a rate controller.
지원되는 모든 기체에 대해 자동 튜닝이 작동됩니까?
The mathematical model used by autotuning to estimate the dynamics of the drone assumes this it is a linear system with no coupling between the axes (SISO), and with a limited complexity (2 poles and 2 zeros). If the real drone is too far from those conditions, the model will not be able to represent the real dynamics of the drone.
In practise, autotuning generally works well for fixed-wing and multicopter, provided the frame is not too flexible.
자동 튜닝은 얼마나 걸립니까?
Tuning takes 5s-20s per axis (aborted if tuning could not be established in 20s) + 2s pause between each axis + 4s of testing if the new gains are applied in air.
A multicopter must tune all three axes, and by default does not test the new gains in-air. Tuning will therefore take between 19s (5 + 2 + 5 + 2 + 5) and 64s (20x3 + 2x2).
By default a fixed-wing vehicle tunes all three axes and then tests the new gains in-air. The range is therefore between 25s (5 + 2 + 5 + 2 + 5 + 2 + 4) and 70s (20x3 + 3x2 + 4).
Note however that the above settings are defaults. A multicopter can choose to run the tests in air, and a fixed-wing can choose not to. Further, a fixed-wing can choose to tune fewer axes.
Anecdotally, it usually takes around 40s for either vehicle.