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MAVLink to ROS gateway with proxy for Ground Control Station
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Normalized throttle value for SITL on gazebo using mavros #469

Closed Jaeyoung-Lim closed 8 years ago

Jaeyoung-Lim commented 8 years ago

I am using a custom built quadrotor to fly offboard using MAVROS

I measured the actual thrust compared to the normalized throttle value in the topic(/mavros/setpoint_attitude/att_throttle) to implement a offboard control code using attitude control

However, trying to use IRIS in the gazebo simulation with mavros, I have no idea what the normalized throttle values should be for the IRIS model

A guideline is needed for the thrust generated compared to the normalized thrust values at least for the standardized quadrotors such as IRIS or Solo

vooon commented 8 years ago

http://mavlink.org/messages/common#SET_ATTITUDE_TARGET

Jaeyoung-Lim commented 8 years ago

@voon

What I mean by mapping is the thrust in N(force) to the value of throttle!

vooon commented 8 years ago

I don't thing that FCU operate in newtons (because it depends on many factors like battery charge). So i do not have quick answer.

Jaeyoung-Lim commented 8 years ago

I understand. But we need the scales of normalized throttle value in order to fly in rate or acceleration control

Currently we are just measuring the thrust by experiments to match the normalized throttle values to N

However for standardized quadrotors such as IRIS which can run px4, if we have a guideline of on which battery voltage and thrust value creates which thrust(by real dimensions such as N),

It can reduce the need for time and equipment to find the throttle value!

IeiuniumLux commented 7 years ago

@vooon , why did you close this? I believe the main problem is that the on-board pid controller uses normalized thrust values @Jaeyoung-Lim is trying to use absolute thrust values instead.

Was a guideline or map created to resolve this?

ZhongmouLi commented 5 years ago

Guys, have you finally found the mapping from the thrust force to the normalized thrust value?

atharva417 commented 3 years ago

Hi @Jaeyoung-Lim How did you finally find the normalized throttle values? I see you have used norm_thrust_const_ * ref_acc.dot(zb) + norm_thrust_offset_ Can you please explain how to select the parameters 'norm_thrustconst' and 'norm_thrustoffset'