Would you buy a raspberry Pi based multiplexor/datalogger if it was easy?

Would you be interested in a raspberry pi based data multiplexor/data logger if it looked easy?

  • Yes, sounds very interesting

    Votes: 10 35.7%
  • No thanks, not for me

    Votes: 10 35.7%
  • maybe, but would like to know more first

    Votes: 8 28.6%

  • Total voters
    28

GHA

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I find this a hard one to consider as everyone has their idea of what they want.

I have a Multiplexor ... cost me about 50 euros incl shipping. WiFi2NMEA (eBay seller ,... he now offers the WiFi4NMEA unit )..... the only item it does not have - NMEA2000.

No programming needed ... I just connected gear and it outputs WiFi and USB as well as NMEA0183. I accept that being 0183 and only the 2 version - I will not have temp .. fuel gauge ... wind etc integrated, but really at end of day - do I want a screen populated by so many boxes ? I sit at helm and glance down at fuel gauge ... I glance up at wind indicator ... I feel cold or warm .... my Tablet and plotter have AIS / GPS with all the relevant data of speed, dist run, DTG, BRG, position, time and battery voltage ............

Not knocking Rpi or setups with all the data etc. It comes down to what a person wants.
Yep, couple friends have those and are very happy. From memory it's an esp8266 & a few components and code. In my world it woud be opensource but also in my world that guy should be free to do what he wants and really no point having an opinion of it one way or the other..
What would be nice to do would be show that a little rpi setup can be had for not much money & isn't as scary as many think. No comparisons or value judgements of anything else.
 

GHA

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One item that is missing with Raspberry Pi is a safe shutdown routine. Fine if you always send sudo shutdown -h now, but on a boat that has multiple users, many just yank the power which can corrupt the SD Card.

Would love a little battery board that recognised power loss and initiated an immediate safe shutdown.
good idea, been done so must be circuits knocking about. Something to give power for a little while to cope with voltage drops during starting would be nice s well.
I use a nodered dash for a load of things inc shutdown/reboot.
 

ylop

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Easiest solution will likely be just deselect the bits you don't want in the BOM in jlcpcb.
Ok - if you are looking for constructive criticism of the idea - I will happily buy stuff, wire it together and configure it in RPi so I'm probably already "more advanced" or at least "more confident" than your "target user". I've never ordered anything via jlcpcb before so that's an extra step into the unknown for me, and to then be deselecting bits of the BOM could be a step too far even for me. I believe you will put off exactly the sort of people you said you were trying to appeal to. On the other hand if the design was the right price and had nice features you might well appeal to people like me - one issue to consider would be lead time I want my toys this week not in a month. To be honest a simple, well supported, well documented "Boat HAT" that came with the most common interfaces might have got an order from me. I'm not the user you described but if it would have saved me sourcing parts, wiring them and mounting them and I knew it would work out the box rather than trying to unpick internet debates about 4K7 v's 10K resistors....

Indeed why woud you mess about with mongodb these days when influx exists??
Because I've never heard of Influx, but I use MongoDB in other parts of life so no learning curve. It has a SignalK plugin so should be trivial to add. Perhaps Influx is even better, but its one of the headaches with OpenSource stuff is there is no cohesive strategy so I might decide to go Influx then in six months the world decided Mongo or some new_fangled_toy was flavour of the month and I'm left with a bunch of technical debt trying to work our if I keep nursing it along or undo any effort that's gone in.

No downside, it's free.
rarely is anything truely free - how are Influx funding it and what happens if they go pop or turn on a charged tier and i'm locked to their platform?

However I'm guessing from your reply you either live aboard or leave your boat permanently plugged in so you can see the trends over time? I don't do that, I'm not sure I'd gain enough value from the data to do that. Its great that you can. if you aren't needing to make an ROI then if you don't find any other people wanting the solution then I don't think that's a problem.

And tbh inspired with posts similar to this, a fair bit of misinformation and negative opinions which just scares people off even more.
It's sadly very common on ybw nowadays. Much less so elsewhere.
are those other places tech / geek "fora". Those people may well be interested simply for the sake of doing it. Here you will get the why? that may seem critical but I think those questions are actually really purposeful because they direct you (if you choose to take it) towards things which might actually be of wider use.
 

Refueler

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Yep, couple friends have those and are very happy. From memory it's an esp8266 & a few components and code. In my world it woud be opensource but also in my world that guy should be free to do what he wants and really no point having an opinion of it one way or the other..
What would be nice to do would be show that a little rpi setup can be had for not much money & isn't as scary as many think. No comparisons or value judgements of anything else.

You'll be lucky - you know full well that there is someone on these forums that is dead anti anything like this !!
 

Keith-i

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These forays into RPi interest me although I have to admit it’s probably very much finding a solution to a problem I don’t have. I use a Pi at home to filter out adverts on websites which works remarkably well so I’m quite sure there’s mileage for one on my boat.
The idea of a BoatHAT is tempting as half the trouble is getting connections simplified. I don’t have any particular desire to log data but if it can double up as an access point for wifi that sounds useful.
It’s perhaps noteworthy that I have a couple of Arduino boards converting engine data and cabin temperatures into N2K so that they show up on my plotter.
I think any system has to be very modular so that you can pick and choose the elements you want.
 
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@GHA when will you be starting your YouTube and Patroen "How to cook a Rasberry Pi" channel?
 

GHA

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The idea of a BoatHAT is tempting as half the trouble is getting connections simplified.
Yep. I've been using network ethernet cables with some little breakouts off ebay, and playing around with having similar on a board, 2 little breakout boards which might snap off the main board. Tidies things up loads. This isn't anything, just a play to see if it looks like it might work. Should do.

image.png



I don’t have any particular desire to log data but if it can double up as an access point for wifi that sounds useful.
It will actually work just using the onboard wifi which creates an access point and connects to a network. Though not stable so best to get a separate usb dongle . Think I might be alone in finding plotted data fascinating :ROFLMAO: Like the blip in pressure in Europe after a volcano eruption out near Fiji somewhere.

I think any system has to be very modular so that you can pick and choose the elements you want.
That shouldn't be too hard, just unselect the expensive bits you don't want. Might be nice to have headers next to surface mount chips so you could have a nearly bare board & add ebay sensors later if you want.
But nothing is anything yet, this post was just a little test the water and there does seem to be a bit of interest among the doom and gloom.
 
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GHA

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What do the racers use to plot data? Will be very interesting stick a waypoint in on the rhumb line a few hundred miles away then watch vmg, see if bearing a way a bit or not, should be able to see down to maybe 0.1Kts averaged. Doubt if a eye on some numbers would stand a chance of getting anywhere near that. Sail trim could get a bit more obsessive :unsure:
 
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st599

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good idea, been done so must be circuits knocking about. Something to give power for a little while to cope with voltage drops during starting would be nice s well.
I use a nodered dash for a load of things inc shutdown/reboot.

I'm guessing that it could be done with a small battery charging IC. Pi takes power from the battery which is charged from the incoming boat supply. Pi has a cronjob measuring incoming, pre-IC voltage, if it drops below say 3v, shutdown.
 

GHA

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I'm guessing that it could be done with a small battery charging IC. Pi takes power from the battery which is charged from the incoming boat supply. Pi has a cronjob measuring incoming, pre-IC voltage, if it drops below say 3v, shutdown.
Been mulling over it all, think the way forward today is keep simple. Would really like to update the board on my own boat so just to get the ball running look at getting that together with an eye to the future. Spent a while looking at power supplies but for now easiest just to maybe provide a bit of protection on the way in to allow for a circuit later, mine gets powered from a hifiberry audio amp so for that it doesn't even need 5v. Rushing to get lots bells and whistles never really works. Power down/reboot button would be easy to implement in node red, which works quite well as it's simple to save & share without diving into cron. Nothing node red can't do :cool:
Here's current esp32 based board. GitHub - boatybits/boatymonpy
The esp has can controller which Pi's don't which should make it easier to get n2k data in/out. Signalk has reverse engineered N2K installed already.
ACS712 was a waste of time - just used up an ads115 input, ina219 works very well, had that monitoring a shunt before. RPM apparently works fine. ADS1115 ar great, an op amp voltage follower might be nice on the way in.
Multiplexing an input into the MAX232 might be really useful to get non critical serial data in, currently :)ROFLMAO:) the VE direct from a smartshunt goes straight to a pin as it is 3.3v but most victon gear VEdirect is 5v.
Would be nice to have holes for headers to allow for ebay modules as well as surface mount, that could allow for a cheap but powerful testing board
And lots i2c headers, header for a nokia screen, header for an E-ink screen... gotta be enough to be getting on with :unsure::ROFLMAO:

Thanks for the comments everyone - poll looks neck and neck ......

Schematic_BoatMonitorSMD_Sheet_1_20200209152710.png
 
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Neeves

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I prefer to go sailing. There is enough work with boat maintenance not to go down this particular rabbit hole.

I'm with Sandy.

I'm quite happy to monitor the sight tube on our fuel tank and use a dipstick for our 2 water tanks. Knowing the answers does not alter the reality. I'm happy to go from A to B inefficiently - Its the sailing I enjoy not how efficient I am, or not. Our navigation relies on a compass heading (actually keeping land at a specific distance, determined by eye) and counting lighthouses and for pure sophistication correlating SOG with speed through the water (in or out of the dominant current)

Now - if I still raced - different story entirely. I might suggest looking at the 'Racing'
part of the Forum......? or specifically initiating a thread on such.

Jonathan
 

GHA

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I'm with Sandy.

I'm quite happy to monitor the sight tube on our fuel tank and use a dipstick for our 2 water tanks. Knowing the answers does not alter the reality. I'm happy to go from A to B inefficiently - Its the sailing I enjoy not how efficient I am, or not. Our navigation relies on a compass heading (actually keeping land at a specific distance, determined by eye) and counting lighthouses and for pure sophistication correlating SOG with speed through the water (in or out of the dominant current)

Now - if I still raced - different story entirely. I might suggest looking at the 'Racing'
part of the Forum......? or specifically initiating a thread on such.

Jonathan
Only 2 so far, not that bad really.
You are fortunate in having the choice to do what you please.
I'm not very keen on celery.
Don't see the point of telling people who are talking about things to do with celery though.
Why would I ? Adds nothing of use and nobody cares or is in the least bit interested in my opinions about not liking celery.:unsure:;)
 
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Neeves

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Only 2 so far, not that bad really.
You are fortunate in having the choice to do what you please.
I'm not very keen on celery.
Don't see the point of telling people who are talking about things to do with celery though.
Why would I ? Adds nothing of use and nobody cares or is in the least bit interested in my opinions about not liking celery.:unsure:;)

Good to see you took the trouble to comment, we know where you stand.

It takes all sorts.

Sad really.

Jonathan
 

Refueler

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Good to see you took the trouble to comment, we know where you stand.

It takes all sorts.

Sad really.

Jonathan

I don't think its sad ... its just differing viewpoints.

This is Practical Boat Owner RtR forum. Over the years it seems to have lost its DIY / Practical side. Seems to have gone the way of the PBO Sketchbooks ....

It takes all sorts in any hobby / pastime. Some like to tinker and create ... others like to buy over the counter. I tend to think I sit in the middle appreciating both when they are civil and accepting of each other.

If I had not found various items to put together setups I use(d) .... I might have chosen the Arduino / Rpi route ... why not ??
 

ylop

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@GHA - 12V to 5V power supply is a good shout, I'd forgotten about that, it was an easy enough option to source but was yet another "will it work" and "where will I mount it" problem.

Not sure if you've found any use for relays yet? I've got a board with relays sitting on it here because I originally assumed it would be handy to let the pi turn stuff on and off but haven't actually found a need yet. If I had a remote monitoring set up then it might be from 100 miles away it would be quite useful to turn on/off heater/dehummer etc either automagically or when I look and see something I think need attention. I could imagine that arriving at the boat on its mooring on a dark evening it might be nice to remotely turn on the heater and some deck lights perhaps just as before we launch the dinghy.

And if you want a real challenge! Boat is sitting 100 miles away with a Pi on it, its all up and working nicely. Its a wet winter wed evening and I want to update / change the config on the pi / test something etc. A board that emulated the incoming data to the pi would be great - I'd have a separate identical set up here but instead of being connected to the instruments it would be connected to the emulator - it could even take your data recorded on the boat and feed in back into the home set up to see if an alarm you want to set etc works?
 

AngusMcDoon

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Some like to tinker and create ... others like to buy over the counter. I tend to think I sit in the middle appreciating both when they are civil and accepting of each other.

I like to have both two, and pure bliss when my expensive toys talk to and co-operate with my bodged stuff - as my recent project getting my black box to show the exhaust temperatures and sound alarms on my Axiom+ displays.
 
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