Hi everyone,
my copter is flying stable in Loiter, then suddenly starts climbing. I can only stop this by changing (at 50 feet or so) to stabilize mode. Wind 10..15knots.
Data flash log says, climb rate goes negative, baro_alt rises (i see it climbing, and signal values rise), and inertia_alt goes up about half the baro altitude.
GPS seems to change some satelites, no errors, no Nlon HDop is OK.
Can anyone help me:
1) when the sign of the climbing rate is negative, I sink = is that right?
2) how does the APM calculate IAlt and IClimb?
3) does anyone know about feedback from Motor/Prop noise via the IMU sensors to the controller, causing an undesired climb rate?
Thanks for any help!
Greetings, Hans-Jochen
Replies
dennis
Hi Dennis,
I think there is a chance of changing the software, but we need a discussion of the architectural design.
Designing a filter for altitude estimation will say, how many different signal sources do I have, how do they depend on each other? Can I use data from an implemented EKF, or do I have to build this first? What about the time slices and the CPU capacity?
Have a look in the "drones-discuss" forum, and find out what chance our idea has (just being heard!).
I think, for the winter I will change my apm1.0 to 2.6 with a separate gps-compass combo. Maybe this solves already some of the actual problems?
Kind regards, Hans-Jochen
did you ever get an answer to how IALT and ICLIMB are determined?
dennis
Hi Dennis,
sadly I got no answer, but I thought about starting a thread about altitude calculation.
The last time I had the APM in the air, I had a dozends of stable flights.But there is always a kind of drift in the altitude, e,g, starting loiter at 5 Meter ends up ten minutes later by touching the ground (sonar not activated).
Anyone welcome building an "altitude estimator", connecting the sensors and other inputs. I have done things like this in my daily work when developing software functions on speed and mass of vehicles, so I would like to share this experience with the forum users.
I have already written down some notes on that issue, I think there should be no problem to discuss, review and integrate them on a new SW step.
Greetings, Hans-Jochen