Hi everyone !
I am having a trouble with a drone. The drone has a good behaviour at low speed. However, for a high throttle input (without any roll, pitch or yaw command), and so a bit of speed, the drone is very unstable in ACRO mode. Indeed it turns backwards like if there was a pitch command (so the front wing is higher than the back wing). It also rotates on the right, like if there was a roll command. This rotation is very quick and can become more than 90° (even almost upside-down drone) is 2-3 second.
In STABILIZED mode, I still have the problem but it is less important as the Pixhawk controls the angle (instead of rotation speed in ACRO), causing only a drift (instead of a complete rotation).
Here is flight log where you can see the problem in STABILIZED and ACRO : https://logs.px4.io/plot_app?log=4fd57545-c059-40a5-a229-187eb2c33c26
The pilot performs vertical accelerations (see Manual control inputs) and we see that Roll/Pitch or Rollrate/Pitchrate deviate from the setpoint without any correction from the Pixhawk.
Do you guys have any idea of the cause of the problem ?
Here is the setup I use :
- Pixhawk 4
- UAVCAN communication for the motors. Main mixer (IO).
- VESCs as motor controllers.
The drone is imbalanced in yaw but we tried on a balanced drone and had the same problem.
Thank you in advance for your help !