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Electronic package topside, Camera, light, depth and temperature sensor subsea

Would it be possible to connect the light and sensors of the BR2 electronics to a diver umbilical and control it via QGC. I suppose the light and sensors would be ok, but what about the camera? Is there any way to feed a distanced camera into QGC for recording? Would QGC accept that there is no motors etc. ?

I dont think so as the i2c/USB connections can’t be sent long distances. You need to have the Pixhawk/Pi close to the sensors/USB camera.

In terms of not having motors connected, thats no problem. We have units that have all the electronics in a subsea enclosure, running up to QGC for view/control

Hi @SDI while this is obviously not the intended application for the electronics/qgc, it could be adapted to work.

I suggest trying to do something custom, because you do not require a pixhawk, qgc or raspberry pi to do all of these things necessarily. Your project application is so different, that you will probably be able to cut significant cost and time if you started new. This all depends on the level of hacker in you, but that can always be developed and improved :).

Jacob, I sent you an email about doing something like this today. about maybe just two lights and a camera for a diver hat.

I’ve had some success streaming video to QGC using the BR camera and Raspberry Pi Zero with an external miniature Ethernet/USB-hub USB dongle. This was over a hard-wired ethernet connection so far. I’m trying to pack everything in really tightly, so the Fathom-X is too big for me (if it even actually fits in a 2" tube, I don’t have a spare to check).

Hi Dan thanks for the response. Do you have any pictures or detail information. I am really interested to try any get something working for our dive set up.

Thanks

Dustin.

Hi Russ,

Is it specifically two light and a camera you need, or other sensors aswell? If so, any specific reason you dont want to use analogue cameras?

Hey, Dustin, I don’t have pics or much detail to share, but I can tell you I used a Raspberry Pi Zero W and https://www.adafruit.com/product/2992

I’m running Raspbian Stretch on the Pi. I think that gstreamer/gst-launch-1.0 is installed by default and that installation works to stream video, but I can’t tell you that for sure.

The hardware/software config is like the diagram shown here:

However, the USB camera doesn’t require the raspivid software part… and there’s no pixhawk so you don’t need the MAVProxy part.

gstreamer is software that reads the video from the camera and sends it over the network to QGC. It is launched by a gst-launch-1.0 command as discussed here:

Again, I believe, unlike the issues I had in that thread, that the gstreamer installed on recent Raspbian (or at least installed using the apt package manager) is fine, but I’m not 100% sure. I’d have to try it with a fresh install, which I can’t do right now.

My tests so far of the video streaming from the Blue Robotics USB Low Light Camera with that Adafruit USB hub and Pi Zero were limited to a quick go/no-go check to see if it was basically feasible, and it seemed to work okay. I haven’t stress-tested it, and I don’t have good notes about precisely what I did with it, but I think since the camera handles the compression, the Pi Zero doesn’t have that much to do.

So I think what that means is you have

The BR usb camera the usb plugs into the ethernet hub the hub plugs into the Pi zero W all that will hopefully fit into and dome enclosure the tether has a ethernet end and penetrator. Then what happens on the topside? Just ethernet straight into a laptop and it works on Qground? Have you or any tried lights?

The BR usb camera the usb plugs into the ethernet hub the hub plugs into the Pi zero W all that will hopefully fit into and dome enclosure the tether has a ethernet end and penetrator.

Yes, though I haven’t actually used it underwater, so I haven’t thought about an ethernet tether and how to do the penetrator. I’m going to make a smaller board to use a Homeplug/Fathom-X style connection with soldered Ethernet wires between the hub and Homeplug adapter.

I should also disclose that I don’t think it’s possible to fit it in a 2" tube with the stock micro USB connector on the Adafruit USB hub. I opened up the hub and replaced the cable with one that had a right angle connector. The width of the new connector + pi zero board is just small enough to fit in the 2" tube. It’s hacky for sure.

Just ethernet straight into a laptop and it works on Qground?

I had it plugged into a switch but it should work fine plugged into a laptop with proper IP address configuration. Unfortunately I can’t verify right now, but I will if I get a chance.

I haven’t tried lights.

sounds good i am going to look into this more but I was thinking if possible to split the tether with a 3m splice kit to what ever wires are used for the camera I am assuming only 2 pairs are used and use the other two pairs to run enough voltage down to run 2 lights possibly.

@Atmoinspections

You might be more interested in the analog video and ourFathom-S board. This requires just the camera, interface boards, tether, and topside monitor, no programming or computers involved.

You could also hook up a switch to flip it on/off topside (lights included).

Hey Jacob. So I was looking at it. And was thinking about ordering. The following —analog camera

-the 2 inch enclosure kit with flat acrylic end. Endcap with 2 holes.

  • one Led light.

And you mentions the fathom S board kit. So will that one board fit in side the 2 inch enclosure? And hook the camera to the camera ports. And a single light to the serial port maybe? And the the top side board we can rig to some

Monitor. Is there anything else you could recommend before placing the order?

We already have a 100m tether.

Regards

Atmo.

@Atmoinspections The ROV side Fathom-S board is 2.5 in wide so that won’t fit in a WTE2 Series (2 in ID). It will fit in a 3" WTE if you want to go that big.

The serial port on the Fathom-S was designed to connect to a Pixhawk and use the Pixhawk and ArduSub for control. The Lumen lights have PWM control, not serial so they would need to be connected to the Pixhawk and not the serial port.

I would recommend figuring out something for power and power distribution.

Ok. I think 3” is getting kind of large to have on top of a diving helmet. so unsure. Any other idea to incorporate our 100m tether into our diving umbilical. To have a live feed camera and a single light? I know this isn’t what your probably too interested in. Just thought I would get an opinion.

Thanks in advanced

Dustin.

Also was just looking the the board again. On the side it claims the board is 1.81” x 2.51 could it not go in side ways to fit in the 2” enclosed?

@Atmoinspections I may have mispoke earlier. I had a customer late last week who found that our imperial dimensions were wrong. I corrected the dimensions for the product page.

I’ll test fit a board on Monday and see if any of the other board components hit the tube when sliding in. I’ll post the results here.

Great thanks, also was wondering, I see that you sell the lumen wire by the Metre. would it be possible to get that cable around 100M with a single lumen on it? then hook it to a topside power source? If so that would be perfect for dive lights. and then if the board fits into the enclosure with and analog camera. we would be set. I would place the order Monday if this is all possible.

Thanks for the help.

@adam can chime in if he has any more specifics, but basically PWM signal communications are designed for short range and not going to work at 100m. We usually tell people who ask, 25m is about as max as you can expect.

We typically don’t do custom items because our production system is not set up for low-rate custom items. We would need to reconfigure our jigs for 100m of cable if you wanted to try it, regardless of the physics. For custom pieces, we also have a minimum order quantity of 50, so if you wanted to try a one-off, splicing 100m of cable onto a Lumen would be your cheapest way of trying it.