Stabilize mode like Loiter mode !!!

As the title say "Stabilize mode like Loiter mode !!!"

I flight my quad copter last night, i have two question.
1) Why stabilize mode like the loiter mode very stable ??

About stablilize mode , it is using GPS and Barometer ??

2) If i flight my quad copter in indoor ,it is same stable ??

My Important Assembly :

1)Pixhack flight controller

2)Align GPS/Glonass module

「apm stabilize loop」的圖片搜尋結果

and about this control loop , the stabilize mode using gps to calculate DCM ??

how to design my flight controller can be stabilize like APM 3.4.X ??

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  • The (primary) estimation of attitude now in APM 3.4 utilize the "Extended Kalman Filter" algorithm. The method combines all the information including accelerometer, gyro, magnetometer, barometer, GPS, and so on.

    Theoretically the algorithm it can work with only accelerometer, gyro, and magnetometer. Under this mode, ofcorse position cannot be observed.

    DCM can refers to the old method of complimantary filter (the corresponding algorithm to Kalman Filter), or simply the "Direct Cosine Matrix", the rotational matrix that can be used to represent the attitude in space.

    For this figure, I think the DCM refers to the later, that is the attitude of the vehicle.

  • There are 3 flight modes you could look at.

    Stab is just pretty much auto level that uses the mag/baro

    Alt-Hold which is basically stab + holding altitude using the baro

    Loiter uses the GPS to calculate position and tries to keep it there.

    And finally POSHOLD which is pretty much all those combined.

    None of the modes that utilize the GPS though should be used indoors as interferance and other factors can make the GPS unreliable.

    Here is a full breakdown of the APM:Copter flight modes.

    Flight Modes — Copter documentation
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Shivchand Jaysaval liked Shivchand Jaysaval's profile
Aug 25