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Advice for using/hacking ST16 for Fathom ROV

I tried three different sources to open the .sch and .brd files from the Electronics folder in the GitHub project for the Fathom One. All say the files are not formatted properly.
Ugh odd.... They opened sorta okay for me using the first or second online converter I found. But, I had to install GitHub desktop to grab then upload them... Crap, hopefully I didn't mess up the original files. I will have to look into that and see what happened. I would "think" that I couldn't edit somebody else's repository...

By "sorta okay" they all had different problems. One opened up a BOM/key, another just opened up the draft signature box, and another opened up a working zoomable diagram, but had words overlaid and incorrectly sized. So maybe the problem was with the files to begin with, and not something I messed up.
 
About the network stuff:
Sorry, again I must ask questions to understand whats going on.
- From the OpenROV manual I understand that the thetering is a 2-wire connection with a top end that has network for control and USB for 5V power. Is this right?

HE, no I have put out lots of information, and have made it hard to follow I am sure. Especially English not being your native language. I am sure my fellow English speakers have had trouble following me, you're doing fine!

1) I think your understanding of the OpenROV is perfect. Or good enough. I don't know that the topside needs 5v power from "on top", I think it takes it POE style from below? Or maybe it is powering up the 5v topside, that turns the ROV on... Whatever the case, yes, it is a 2 wire ethernet connection.

It does this two wire connection using a homeplug adapter. I think that other than the physical testing it with a network cable tester, the function is identical to a network cable. It has a big advantage that it can go further than 100 meters without signal loss. Where the normal network cable is limited to about 100m.

2) I am pretty sure you can even use a standard network cable with the OpenROV. Not sure why one would (other then Fathom), but let's just ignore this.

3) The Fathom DOES use a "normal" type of ethernet cable. I think it has 8 wires going through the tether, with a standard network cable plug on the AP side. No idea what is inside, but probably another network plug.

4) The reason I have been talking about the tree different systems, A) the Fathom, B) OpenROV, and C) ArduSub is that both B) and C) give me ideas as to how A) the Fathom system works. The differences are,

A) Fathom uses a Raspberry Pi 3 Model B. It has a shorter 100m tether and does not use the homeplug 2 wire converter. It has its own Fathom android app, that currently doesn't work on my ST16 controller. But the Fathom app did install on the cheap Walmart tablet.

The Fathom's Pi is plugged into a custom power/controller board. It plugs into here with the raspberry GPIO pin header row.

B) OpenROV uses a BeagleBone Black. It has a longer 2 wire tether with the homeplug adapter. There is no app, it is all webpage based.

The OpenROV is also plugged into a custom power/controller board. It too plugs into here with the GPIO header row.

C) ArduSub uses a Raspberry Pi 3 model B, just like the Fathom. It has a longer 2 wire tether with the homeplug adapter, but I think it can also use a shorter standard network cable. It runs software on the topside computer. It does not appear to have any android app or control ability.

The ArduSub plugs into a Pixhawk flight controller using a USB cable, not the GPIO header. The flight controller needs special firmware.

I have the complete Fathom ROV. I also have the developers kit for OpenROV, but I can not easily utilize that inside of the Fathom hull. For now, OpenROV is off the table.

Sorry for the confusion. I have spent a lot of time studying the OpenROV platform, and trying to figure out how the Fathom and ArduSub platforms work.

HE, this post is mostly for you. I am going to post this, and then a new one with the progress.
 
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I tried three different sources to open the .sch and .brd files from the Electronics folder in the GitHub project for the Fathom One. All say the files are not formatted properly.
I missed something. Where are the schematics?
 



Copy all the contents. Save it as a text file in Notepad. Take care of the coding. UTF-8 should be. This is an Eagle file. Now, this fancy software migrated to Adobe, so not usable at all. You can look for an old version. The minimum requested is 6.6.0.

SCH1.jpg


BRD1.jpg
 
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Use the attached file. On the Internet, you can use Eagle online viewer by Altium (not tested by me!).
 

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A few steps forward, and a big crash backwards...

The new AP broadcasts and lets me connect to it. It sees the network cable (IE tether) plugged in. The drone also powers up the AP without it being plugged in topside. It appears that the network portion is fully, or at least mostly fixed.

But now the rov/Raspberry isn't booting up... That SD card was likely damaged. Either physically, or by turning it on and off so many times. Apparently that is really bad to do to the Raspberry...

Before I was getting the red power light, and a random blinking green led. Now just the red led. Turns out the green one is for SD card activity. No SD card activity, no boot up.

CRAP, I would probably be powered up and working if I hadn't messed with the card. I can't find an image for the Fathom SD card. I don't fully get how raspberry works... Digging through the files in the Fathom App GitHub Repository I don't see anything that looks like what I might be looking for. But I also don't really know WHAT I am looking for either...

I can grab a new Pi, and hope that the card is okay and boots it up. But getting the Pi out of the Fathom will be difficult. I need a safe way to verify the Pi in the drone is still okay. I wonder if loading the ArduSub software up will be safe?

There is an "update drone" option in the android app menu.

I am lost here. I will start with hopefully safe and simple and try the update drone option. But I am not actually connected to the ROV according to the app. I might have to try getting a "noobs" image onto an SD card, then see what happens.
 
Thank you Vaklin! The schematic doesn't tell me much useful, but surprisingly that board file does! Between that and the "confidential internal" Fathom build document, I can actually figure out where all the junk is hidden under the foam.

Did you see a BOM of what components were on that shield? I am interested to know if there is a compass on it for instance. Is there enough information there to actually make another board?

I have another Pi on the way, but I don't hold out much hope that the card is okay. Even dealing with the foam that is in my way, the hardware approach of a bad Pi would be easier for me to tackle.

I have to be SUPER careful here though... There is a lot going on that I know almost nothing about. I have already gotten myself into hot water trying to explore/poke/ and prod too much. Messing that card up has really cased problems.

I think my strategy is to go in this order.

1) Try powering it all up again, maybe it will just finally work. Haha probably not....

2) Fix the last wire on the tether, try booting up again. I hold out zero hope for this being the issue. But might as well fix what I know needs fixing first. I thought this was the POE wire, but the AP powers up without it or external power supplied.

3) I kinda want to explore the tether wiring some more. Maybe knowing what wire that is in a network cable scenario would tell us something interesting. This gets pushed down the list though, as I am going to need the network cable tester to make an easy job of this.

Not sure what I should do first:

4) Try loading up noobs onto an SD card, put in the drone. Or the ArduSub image. I can actually purchase this, but will likely just try and figure it out as I would prefer to put some time figuring it out in, then wait for it to arrive.

Noobs I think would be safe, ArduSub probably safe. But I have no way to interact with noobs. ArduSub sends its commands/info to/from the Pi via USB to a Pixhawk. Obviously the Pi in this ROV is configured differently and using the GPIO. But if I kill it by loading ArduSub, while a pain, I am sure I can get it out and replace it.

While I don't know much about the above, there are well documented steps and instructions to do it...

Or the safer approach, but one I know a LOT less about and really don't have clear directions on:

5) Making up a new Fathom operating card. I don't know enough about Pi to do this, so it is more like "repairing" the damaged card. There is some hope the files on it weren't damaged but the boot info was. This apparently happens when you power on and off a Pi lots of times... If it is this and not the physical damage I did to the card, then I may be able to dig the important info off of it.
---------------

If anyone who knows Pi can look through the two Fathom archives and tell me if the information is in them to create a new operating card, I would be SUPER GRATEFUL! I would actually pay for a card or an image I can use to accomplish that.

My final solution is to gut the ROV and install either OpenROV (ideally, as I have it already) into it, or ArduSub. OpenROV appeals to me more. There is a lot going on with that platform, and it looks like a new OS is in development for it. But the control/power board looks like fitting it in the ROV will be problematic. And ArduSub currently has a LOT more users and information out there on it. Plus it is possible I can just install it and configure it for the Fathom power board. If not, its controller board is at least obtainable.

Both the Fathom and the OpenROV boards are out of production. Files are out there for both that might be enough for somebody to make a new board up. But I would likely need a lot of help to do that. ArduSub is something I can assemble with much less help, if I have to go that route.

For now ArduSub is probably just an experimental OS to pop in and try out. See if I can get some life out of this beast.
 
Don't override the power of schematics, dude...
HAHA I feel special! Hey, I am already exploring with this ROV, WAY outside my comfort zone LOL!

I have put lifelines out everywhere I can think of trying to find the image file. I think that is my best chance. I think I will try the Noobs then the ArduSub images in the meantime. Maybe one of those will allow me to connect, and HOPEFULLY the "update drone" in the app actually fills in the blanks and gets it operational...
 
Okay some small progress! I got ArduSub downloaded onto an SD card. Installed it in the ROV. Can't access anything yet, but the green light is back on. Right. So moved the card back to my MacBook and took a look. I am seeing some familiar looking files on it. But I still can't sus out if the files I need to rebuild this Pi image are in the repositories...
 
My network tester came. It found another open wire in the tether connector I need to fix. It could have been what was stopping the signal. But I suspect that mostly stuff just isn't configured right.

So, I am going to have to swap out the control system to run with the whole ArduSub setup. The parts I need will have to come from China. If so, this will force some patience on my part. I am teasing the foam out slowly. After a bunch of research, it seems like lacquer thinner might actually do something to the cured foam.

Dumping some thinner in there and letting it soak sorta softened the foam. Enough I was able to start digging it out. The Pi is destroyed, but I got the power/control board out mostly intact. It will take some careful cleaning and resoldering connectors, if I make use of it. I probably will as it turns the drone on, distributes power to the ESCs, powered up the POE, and several other functions. The other functions I can probably use the Pixhawk to control easier, since modding and altering code isn’t something I can pull off easily (if at all).

I will have to replace the foam... I won't go cheap on that, and will get the high density 625 stuff I found. Somehow, I need to stuff an aluminum case or something like that in there first. I destroyed all the wiring inside and have maybe half of it out so far. The ESCs were all buried in it. The charging port on the bottom, destroyed. The tether connected on top, destroyed.

I need a strategy that allows me to quickly pull the whole electronics package out, but also is an integral part so I can foam fill the wh
I will have to replace the foam... I won't go cheap on that and will get the high density 625 stuff I found. ole again for strength and waterproofing. I want access to anything that might have to be serviced.

Yeah, the PDB for the Fathom apparently has a compas onboard. The esc power out and PWM out are on it. The lights connect to it and seem to have PWM output. There are two thermal battery sensors. And the depth sensor.

IDEALLY, it would be smarter to just use the Fathom PDB compliantly. But I probably need the Fathom Pi image to have ANY chance in making that work.

There isn’t a lot of room, but with the right aluminum case, the Pixhawk looks small enough that I think I can get it all stuffed in.
 
I should be able to turn the schematics into PDF docs soon. I got a 6 month license from Altium and supposed to allow output in PDF format.

Well this is odd. The files that open fine in the online viewer error out in the downloadable viewer. Back to tech support for Altium.
 
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Thank you DM! Yeah, you had similar problems the last go around. Odd. I did manage to get the PDB out without too much damage. Some loose connectors, and I may have damaged a cap. Still has a lot of foam on it, but should come off pretty easily with a little mechanical effort like a toothpick/toothbrush after sorting up with some thinner.

Once I have it clean and the new Pi connected, I will sit down with the schematics and start trying to reverse engineer what is what on the GIOP pins. I am hoping it is a simple matter of a settings page to reconfigure offboarding the components from the Pixhawk and USB connection, to the Fathom PDB. Not holding out hope for me accomplishing that, but there is another guy looking to further development on this platform.

My strategy is formed for the rest of the foam. I am going to soak it with the lacquer thinner to soften it up, then pressure wash it out.

Took me about an hour of digging through eBay auctions, but I found a near perfect sized extruded aluminum enclosure to use. It is slightly too long, but the height and width are perfect. Trimming the length, if I have too, shouldn't be too hard. I am hoping to fit the whole length in, it will give me more space to tuck wires.

So parts are all ordered and already starting to arrive. Sorta sucks to abandon the Fathom Control system, but I am going to try and reuse part of it at least. The Pixhawk won't add too much weight. The aluminum enclosure will add a bit, but I have four steel ballast plates, and pulling even one will be more weight off than being added by the additional parts.

Anyways, once I have a clear picture of what the new setup will be and how it will operate, I will get back to sorting out the ST16. It looks like I might be able to run ArduSub off of webpage connections alone. If so, then figuring out the gimbals and buttons for the ST16 should be the only real problem.
 
Hopefully I can get it sorted with Altium tomorrow. Should be able to print the schematics and a BOM of all the parts if they can tell me what is going on.

If you go to the online viewer you can see all of it, but can’t print it out or save it to a PDF.
 

Download 6.6 or any other without Autodesk improvements!

Autodesk is not so friendly with your OS. If you decide to uninstall all the software from this "producer", it will still track your system. For the US maybe this is acceptable, but the rest of the world avoids these products.

----

Altium, SolidWorks, and probably more, just import these schematics and PCB. The native source is CadSoft.de, where the great PCB software was developed.
 
I looked at AutoDesk and they were outlandish as they have always been. As well as Altium’s online viewer works, I was shocked that the downloadable version balks at the same files. I’ll get with tech support today to see if they have an explanation.
 
What a pain! Thanks for the help here guys!!!

Tonight or tomorrow night I’m going to power up the new Pi on ArduSub and focus on just getting connected with the software working. For now, bypassing the tether and all that. If I get that sorted, add the AP back in. Do some exploring and maybe even try to get the ST16 connected. I want to see what I’m dealing with software wise.

As annoying as buying an ROV that doesn’t work is, I’m still way ahead of the curve. $500 got me a LOT. A good looking shell that is complete and well balanced. Thrusters. Battery, charger, PDB. Installed camera and light system. Depth sensor. Picatinny rail for mounting GoPro camera, lights, or whatever. It is a super nice base.

And I knew about the connection issues going in. The OS problem, I created. Oops.
 
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Here are the schematics in PDF format
 

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  • Schematic 1.pdf
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  • Schematic 3.pdf
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  • Schematic 4.pdf
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