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Increasing maximum tilt and roll angle

Hello.
I’m trying out an ROV with Bluerobotics components using the heavy frame for 3DOF. The ROV is running well, however, in the stabilize (and depth hold) mode I would like it to be able to pitch/roll further. It seems limited to 20 degrees pitch and 10 degrees roll. Is it possible to increase this? I understand if this affects the performance.

Hello,

Check the ANGLEMAX parameter.

Hi. Do you mean the ANGLE_MAX? If so, why is pitch Max angle and roll Max angle different?

Hello. I just checked the ANGLE_MAX parameter and it seems to be 45 degrees as default. I suppose this means that this is not the parameter to set to increase (if possible) the maximum pitch/roll angle. Do you know any other way?

Yes

This is because due to a bug, this is scaled with the pilot gains. We have modified the behavior of stabilize and depth hold for the next release so it doesn’t happen. It still needs some tweaking but should show in the beta soon.

Meanwhile you can gain some more freedom by maxing it to 80 degrees.

FYI

Great, thanks for the help! In the AP_Motors6DOF.cpp file there is a frame configuration called “SUB_FRAME_VECTORED_6DOF_90DEG”. However, on the supported frames there is no configuration showing the thruster positions. How is this model actually set up with the thrusters?

It’s like the vectored frame, but the horizontal thrusters are mounted at 90 degree angles instead of 45 degree angles like the bluerov2. So the horizontal thrust is vectored like + instead of x.

Alright thanks. I’ve built an ROV now using the Heavylift frame. When I move quickly in lateral movement the ROV tends to roll significantly and then when I stop it goes back to 0 roll. Aren’t the vertical thrusters supposed to stabilize the roll movement when doing lateral movement?

Are you in Stabilize or Depth Hold? If so, you can increase the gains for the attitude controllers such as ATC_ANG_PIT_P.

Yes I am. I will try to do some changes to the params.