The assembly is done, just waiting for a battery pack to do the first testdive. But as we are configuring a custom controller, I have a couple of questions.
1: Why is there a limit of 15 inputs in the QGC. Yes I know it can be doubled by using the SHIFT function, and I can see that this would be practical using a gamepad with restricted number of buttons, but when You are building a custom one, You rather want to add sufficient buttons to get all the inputs You want. So why? and is it possible that it in the future can be increased?
2: This is more for clarification. On the 8-thruster setup, the lights control and cam tilt, is assigned to AUX 1 and AUX 2 (Servo 9 &10). So when adding the gripper, this is recomended to be installed on the AUX 3 channel on the Pixhawk (Which again i assume is Servo 11) In the instructions for the gripper it states the it is only AUX 1, 2 or 3 that will give You the opportunity to control the arm through a joystick command. Have I got this right so far?
If so, Is it not possible to use the other outputs on the Pixhawk? I see on the drawing that Aux 6 is input signal from the SOS leak sensor. I cant control the Aux 4 and 5 ?
There is a limit due to the software design. Most game pads have 16 buttons. It can be increased in the future.
The other outputs on the pixhawk may be used for ex. relays or lights, but only AUX 9, 10, 11 (servo1,2,3) can be used with the servo functions like the gripper.
2: On the 8 thruster setup, You have allready used all control options available with Lights on AUX 1(Servo9), Camera tilt on AUX2(Servo 10) and Gripper on AUX 3 (Servo 11). So even if the pixhawk still have three more outputs (Aux 4, 5 & 6), we are not able to control it through the QGC?
Aux 4, 5, and 6 can be controlled, just not with the servo 1, 2, 3, joystick button functions. There are other functions that may be assigned to aux 4, 5, 6, like lights or relays.
Is there any news regarding the button limitations in Ardusub?
I cant be the only one finding it practical to have the number increased so the âShiftâ function becomes obsolete We have bulit a custom operator panel with 28 dedicated buttons, and was really hoping this are useable in the future.
Hi @Vegard - this is certainly on our to-do list, but isnât actively being worked on right now, unfortunately. There are a lot of moving pieces between the joystick in QGC and handling that on the ROV. Weâve put some time into designing a solution to expand the inputs, but we havenât been able to implement it yet.
@jwalser may be able to add more or point you to an issue that can be tracked for progress.
Inside the ROV i use the Raspberry Pi to control the Pixhawk, but i only use the Pixhawk as a âflight controllerâ to manage the thrusters and control the ROVâs position in the water. It has extremely limited outputs and i needed more.
So i connected the Raspberry Pi to an Arduino via I2C, and the Arduino to multiple analog output chips (because i needed more than the Arduinoâs 8 outputs) and use it to control my LED lights, extension arms that fold out to get the lights further out to the sides away from the camera, ballast drop system (concrete ingots), air valve control to adjust buoyancy (in case i pick something up and the ROV becomes heavier), TWO 9-dof manipulator arms, sample container drawer extension/retraction, multiple cameras pan/tilt, etc.
I put an 8-camera security-system DVR board inside my WTC. That gives me the ability to send the feeds from 8 cameras up the tether easily. Viewed topside in a Chromium browser window. Two pan/tilt cameras in front, one in the rear, one on top, a fixed one on each wrist of the manipulator arms (so i can stick my hand in a hole torn in the hull of a wreck and look around, or when trying to pick something up, i have two camera angles to compensate for my lack of stereoptic depth-perception). One fixed camera on each side. DVR connects to 4-port router, that connects to an eKL ethernet-to-coax adapter ($45 a pair) that sends the signal topside (instead of the Fathom X pair, which are $160). Raspberry Pi also connects to the router.
People are always complaining the Pixhawk doesnât have enough output channels. But thereâs a Raspberry Pi right there. Itâs akin to the guy who 3D prints a few brackets, then tries to 3D print everything else, including the forever-leaking WTC tube, like his 3D printer is the answer to everythingâŠrather than just buying a piece of pipe from the hardware store.
We have bulit a custom operator panel with 28 dedicated buttons, and was really hoping this are useable in the future. 
