Controlling additional Lumens in QGroundControl

Hi all, I’m a new user setting up my first ROV, and have encountered a hurdle I was looking for advice on how to solve. I’m doing the build for my work, and I wasn’t the one that researched it before ordering or communicated with the vendor.

We want to have 6 lumens, and ordered 1 pre-connected set of four and 2 independent/solitary lumens. I suspect the vendor suggested we daisy chain the 2 independent lumens to the set of 4, as we ordered a Wetlink penetrator assembly block, but we didn’t order the extra Wetlink penetrators necessary to do so. I followed assembly instructions from the beginning and simply wired in the 2 independent Lumens into their own penetrators and PWM channels on the Navigator, but only when I got to testing everything in QGroundControl did I realize there are only 2 light output channels (i.e. “Lights 1” and “Lights 2”).

I messed around in vehicle setup to see if there was any way of adding additional components that can be controlled through a PWM channel, but came up short. I got the lights to turn on by mapping their channels to the camera gimbal, so I know they have power and can communicate with QGroundControl, but now I’m wondering if there’s a way to add more light channels. I don’t think we have time to order and wait for Wetlink penetrators to daisy chain all 6 lights together, as we need the ROV for fieldwork, so I’m hoping there might be something in the software I can do as a temporary fix. It’s not critical that all 6 lights are controlled in tandem, it’s fine if a workaround solution involves brightening or dimming them independently for now.

I’m not very adept at coding or backend software, so if anyone can suggest any relatively simple workarounds, I’d very much appreciate it!

Hi @clay, welcome to the forum! :slight_smile:

If you want them all to operate from the same signal then the easiest way to do that is connect together the signal wires. You could do that by cutting them and splicing them together, or (if you have the equipment available / can get it) you could get a 4 pin 2.54mm header that you plug the three lumen signal wires into, short the pins together (with solder and/or some wire), and add a female to female jumper wire from the last pin in the header to the Navigator PWM output pin you want to control the lights from (with some electrical tape/insulation around the header pin block, to prevent it shorting out other electronics in the enclosure).

If you’d prefer to have independent controls of your lights then you should be able to assign three Navigator pins to Lights1, Lights2, and something like Camera Pan (or one of the servo_n outputs on pins 9/10/11). The main challenge there is having enough joystick button functions to control your three sets of lights while also having reasonable control over the other vehicle functionalities, but that should at least be possible with judicious use of the shifted functions.

Alternatively you could do a mix, and join the two wires from the individual lumens together, and just control them via Lights2.

Thanks for advice Eliot, splicing the signal wires sounds like something worth considering. I’ve spliced basic circuitry wires together before, and I’m wondering if it would be similar. I’m assuming you’d cut all 3 signal wires, join 3 together on one end of some kind of connector, and add one of the cut ends with a PWM plug to the other end of the connector? Do I need a special connector or would something standard from a hardware store suffice?

To elaborate on that question more, would I be ok to use a crimp connector or a heat shrink connector? I don’t have soldering equipment to splice with, so would have to work with a connector from the local hardware store

Posting an update that I spliced the two independent Lumens’ PWM wires together to be controlled by a single pin/channel, which works nominally with QGroundControl’s light mapping. I mapped these 2 lights to unoccupied alt buttons (A+ LB or RB) on my xbox controller and it appears to work well!

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