Dear Developers,
We have an stationary experimental setup that consists of a beam rod whose centre is held by a base column. The joint is designed such that the rod has a 2 DOF. At each end of this rod is a motor, with only one end motor having vectoring capability by means of a servo controlled motor base mount. A platform at the centre of the rod holds the Pixhawk and other sensors.
The firmware had been cloned from the Px4/Firmware repository (https://github.com/PX4/Firmware.git). Based on the experimental setup configuration, appropriate mixers were created. The modified firmware works fine in terms of behaviour in Roll and Yaw with direct controls from the RC proving appropriate mixers are being used. Next, with this being stationary setup, by using 'mavros' we were able to achieve OFFBOARD control and perform trajectory tracking by publishing on the topic "/mavros/setpoint_attitude/attitude" and "/mavros/setpoint_attitude/att_throttle".
Objectives:
Right now, what we are doing with OFFBOARD mode is commanding varies attitudes (roll and yaw) and Pixhawk follows it using its onbaord low level controller. That means the controller for now is running on pixhawk. What we want to achieve is to be able to run controller on our PC so that at the end we can control our setup using different control algorithms. Our aim in the closed loop control is to directly get PWM (or RPM) values from our controller and forward these values to each motor via output pins of pixhawk. That is, we would like to find out a way to bypass pixhawks low level controller so that the ESCs instead of taking Pixhawk commands, take our command directly.
Problems:
In order to achieve this, I have gone through all the topics of mavros package and think "/mavros/RC/OverRide" to be the most relevant but I'm still not sure of how to make use of it. Also I could not find any example for this particular topic so that I can use it for my purpose.
Please, do suggest me if there is any other way this could be achieved if not by the above method.
To Summarize - I want to bypass the Pixhawk low level controller and be able to command the motors from the controller on my system using mavros.
Thanks!!
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