Good afternoon,
RC helicopter Align T-Rex 450 I installed the Mateksys H743-Mini flight controller with the Arducopter V4.5.7 firmware.
The helicopter with the stich in the center does not maintain the howering, but quickly translates forward. Analyzing the final part of the flight log that I attach, where I tried to maintain the howering, it seems that to maintain the hovering 6° degrees of pitch are necessary. They seem too much to me.
Any suggestions?
P.S.: in this flight I inadvertently removed the Notch filter.
Thanks
From the wiki:
If the pitch angle was not zero to keep the helicopter from drifting, then enter the pitch attitude required for no drift in the AHRS_TRIM_Y in radians (which is the angle in degrees divided by 57.3). If it took 2 degrees nose down (-2 deg) to hover then you would enter -0.0349 radians into AHRS_TRIM_Y.
Thanks,
I read and followed the wiki, but 6 degrees seems excessive to me. I would not want there to be some mechanical or electronic setting problem.
How well balanced is your C of G? Was the mast perfectly vertical when you leveled the swashplate and set the blade angles? How level was the airframe when you did the initial IMU leveling? There’s a lot of variables. Yeah, 6 degrees is a bit, so you can go back and check everything else first.
Thanks.
I’ll double check everything: CG, mast verticality/blade angle setting, leveling/IMU.
@Brighela Walter, Did you figure this out? There was no log posted here. I can look if you want?
@bnsgeyer You are right, I did not attach the flight logs. Here it is. Yes, I would be very happy if you could examine it.
Thanks
Walter, Based on what I looked at, i think it is just the AHRS_TRIM_Y that needs to be set to account for the non zero pitch attitude relative to the orientation of the flight controller. So based on your last flight and what you had set for AHRS_TRIM_Y already, I would add an additional 6 deg to the current value which would make it 0.14. Do a sanity check and see that with your rotor shaft perpendicular to the earth that the pitch attitude reads 0 deg.
Hi @bnsgeyer, I put the mast perpendicular to the ground and I configured the “Max Collective” to 10° and the “Min Collective” to -2° as indicated in the helicopter user manual. But when I bring “Zero thrust collective” I get the value of -2.0°. I don’t think this is correct. In this configuration I should get the value 0°; right? To position it correctly I have to act mechanically; right? Thanks
Walter, Yes you should see 0 deg or within +/- 0.2 deg. When you set the max and min collective, you used the Manual collective servo setting (H_SV_MAN) to move the collective to min and max? Then the H_SV_MAN set to 3 to have it show you zero thrust collective?
Hi @bnsgeyer, exactly, I acted on the H_SV_MAN parameter as you described. I redid the max and min incidence after mechanically extending the rotor levers, so I obtained the 0° value. Today I performed a flight in howering, but it seems that the value to insert in AHRS_TRIM_Y is always around 5/6°. I leave you the flightlog; if you can analyze it I would be very happy.
Thanks
Walter, Yes, that is correct. Because your flight controller must be mounted such that it is 5-6 deg off of the plane perpendicular to the shaft. I guess it could be a CG thing but my bet is on the mounting of the flight controller. just set the AHRS_TRIM_Y as I requested above. You should be fine then.
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