APM2 strange behavior

I took my APM2/Y6 out for its maiden today. At first, it seemed ok, a little wobbly, but this is only with a few PID iterations. Something just doesn't feel right though. After some forward flight in stabilize mode, if I return the elevator to neutral, the copter will pitch back drastically instead of levelling and if I try to give it forward elevator to resume forward flight, it will barely pitch forward. I am giving it full forward elevator but the copter is still basically level. If there was more than  a 5mph headwind, there would be no coming back. 

I take it my stabilize gains are too high, but I don't understand why it attenuates my elevator input so drastically. 

I also set up my gear switch for RTL and the planner shows the correct mode when I switch, but nothing happens even after verifying I have a solid blue on the GPS.

Views: 268

▶ Reply to This

Replies to This Discussion


3D RoboticsPermalink Reply by Chris Anderson on February 12, 2012 at 8:00pm

Have you vibration insulated your board as instructed in the manual?

Permalink Reply by chris g on February 12, 2012 at 8:06pm

I used some  futaba foam servo tape (double stacked), similar to how I had my APM1 mounted. Is the APM2 more sensitive to vibes?


3D RoboticsPermalink Reply by Chris Anderson on February 12, 2012 at 8:13pm

Yes, because it's lighter.

Permalink Reply by Johann Van Niekerk on February 12, 2012 at 9:03pm

HI Chris

just off the back off that comment when will the APM 2 be released with 90 degree sideways headers ? its all good mounting the APM 2 like in the manual but in the last picture how must we get the servo wires plugged into the board ? there is no space . I think they should only be done in 90 sideways headers .


3D RoboticsPermalink Reply by Chris Anderson on February 12, 2012 at 9:14pm

We'll be offering right-angle headers in the next batch, not this one. 

Permalink Reply by Nick Sargeant on February 13, 2012 at 1:23am

Chris, is there ant ETA for the next batch?

Cheers.

Permalink Reply by Martin Szymanski on February 12, 2012 at 8:11pm

What I do is hold the copter on one hand (be safe) and pressure it up neutral using the throttle. If your hand is not smooth with vibration(s) across the throttle positions you may have a balancing or other mechanical problem. I test each arm individual for vibration.

Permalink Reply by James on February 14, 2012 at 2:09pm

i have been struggling with the same behaviour on my hexa with v2.3 - impossible to hold an angle against the wind and pronounced "rebound" after forward flight.  for me the key to getting it stable has been setting stab_d to zero and working on tuning the rate parameters.  when im happy with the rate loop i will go back and try to get stabilize values closer to the defaults again.

james

Permalink Reply by chris g on February 15, 2012 at 12:30am

ok, somewhat comforting to know that i am not crazy. will try adjusting the stabilize PIDs as suggested, as well as better mounting. thanks!

RSS

Social Networking

Top Content 

1 APM Project vs DJI NAZA and WOOKONG

APM Project vs DJI NAZA and WOOKONG
2 APM 2.5 with NEO-6M ublox gps (not 3DR LEA-6)

APM 2.5 with NEO-6M ublox gps (not 3DR LEA-6)
3 APM Copter 2.9.1.b has been released

APM Copter 2.9.1.b has been released
4 Flying 3D Spline Curves between Waypoints with ArduCopter 3.0

Flying 3D Spline Curves between Waypoints with ArduCopter 3.0
5 ArduCopter-3.0 ready for wider use

ArduCopter-3.0 ready for wider use
6 10k autonomous flight - telemetry guided flight, and other APM tests!

10k autonomous flight - telemetry guided flight, and other APM tests!
7 Drone shot down by police

Drone shot down by police
8 MAAT final version is being tested

MAAT final version is being tested
9 Getting ready for Arducopter 3.0

Getting ready for Arducopter 3.0
10 Help Tuning Arduplane 2.73 With A Large Slow Airframe

Help Tuning Arduplane 2.73 With A Large Slow Airframe

Contests

Season Two of the Trust Time Trial (T3) Contest has now begun. The fourth round is an accuracy round for multicopters, which requires contestants to fly a cube. The deadline is April 14th.

A list of all T3 contests is here. 

Groups

Advertisement

© 2013   Created by Chris Anderson.   Powered by

Badges  |  Report an Issue  |  Terms of Service