1 Introduction


The Mobula BlueROV 4.4 RC15 (Date:18/02/2020) allows to operate up to 4 auxiliary channels on the ROV’s flight controller, PixHawk.
This requires a special base setup in QGroundControl (further called QGC).
 We are working on an a Mobula design that is independent from QGC or any other ground station software.




2 Setting up QGC


Go to the QGC Camera Setup, and define Camera and Lights channels as follows:

  • Camera tilt servo to Channel 10, which corresponds to AUX channel 2Figure 1 QGC: Camera Setup: Camera tilt servo

 

  • Both Lights 1 and Lights 2 should be configured:
        Lights 1: to Channel 11, which corresponds to AUX channel 3 and

        Lights 2: to Channel 12, which corresponds to AUX channel 4

            Figure 2 QGC: Lights 1 and 2 as Channel 11 and 12 (AUX channel 3 and 4)

  • Set up QGC as shown in the screenshot below.

    Remember that Arming / Disarming, Flight modes, Gain increase/decrease can be separately set up in Mobula. The functions are independent from QGC.


       

         Figure 3 QGC: Set up




3 Rebind keys in Mobula

To rebind keys on the joystick:

  • Go to the Mobula project tree
  • Browse to the Blue ROV node, and right click on the Joystick option
  • Select Rebind keys

       

         Figure 4 Mobula: Project tree with Rebind keys option


  • Select a function you would like to control
  • Click the box next to it to bind a key to it. 
    A small window pops up prompting you to press the button wished to be used for the function. 

       

         Figure 5 Channel mapping in the Rebind keys window


  • Press Save after each change.

IMPORTANT: To test the buttons work correctly the ROV must be armed, otherwise lights and camera tilt are disable at the moment.

With the QGC settings described in chapter 2 you can bind 4 AUX channels (Channel 9-12).
 The channel mapping as described in Figure 5.

 

Physical channel on Pixhawk

Key name in Mobula

Channel 9 (AUX 1)

Servo 1 (SERVO1_INC, SERVO1_DEC)

Channel 10 (AUX 2)

Servo 2 (SERVO2_INC, SERVO2_DEC)

Channel 11 (AUX 3)

Servo 3 (SERVO3_INC, SERVO3_DEC)

Channel 12 (AUX 4)

Lights (LIGHTS_UP, LIGHTS_DOWN)

Table 1 Channel mapping to buttons in Mobula

 

All 4 channels can control servos (camera_tilt) or lights, or other equipment controller by PWM signals.

Remember that changes made in QGC will affect how these settings in Mobula behave.

***This is just a temporary fix until a permanent, QGC independent solution is implemented in Mobula!



 

4 Version descriptions

Version

Date

Author

Description

1.0

18/02/20

BEV

Document created

1.1

25/02/20

BEV

Added additional comments