Rugged tablet, or ordinary tablet with a good case ?

sarabande

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This is prompted by PhilM's recent Plymouth experience and the productive thread arising therefrom.

When solo and in restricted viz or night, I would like to have a tablet to back up my eidetic mind-chart, so that I do not have to set the autopilot and head below to the chart table to use the other nav systems. The tablet would also be used for planning purposes, away from the boat, in conjunction with the charts and books at home.

There seem to be two paths:
1 Ordinary tablet with a protective case
2 Ruggedised tablet


My initial spec (not priority) is:
1 Pocket-sized, about 8inch screen
2 SD or MSD card slot
3 Good multi-source GPS
4 SIM card for phone
5 Wifi (for AIS)
6 Decent memory for apps such as Ephemeris, Star Map, some music/books, etc.


What suggestions or practical experience does the forum have re the type of tablet, and what other specs would be good to have, please ? I am neutral about iOS or Android..

I have a laptop with OpenCPN, and a handheld GPS, but neither is suitable for use when isolated in the cockpit.

TIA
 
I think it's best to have a clear view of exactly how you intend to use this.
I have a Nokia phone which is very good, it works in a plastic bag in my pocket and takes its chance. It was about £100 and has survived a couple of years, if it dies now so be it.
Spending proper money and only wanting it to work on one boat, I'd get a proper water proof Garmin plotter that could be used above or below deck.

But a half-competent passage plan with a few key waypoints in the HH GPS would work just as well.
A bracket to hold the GPS in the cockpit is a good move.
There's a waterproof (ish!) clear pocket on the back of the cockpit halyard bag, used for courses and SI notes when racing.
Key points of the passage plan in there for instant reference is a lot more use than an android toy sometimes.
 
One option would be hunt ebay for a 2nd hand sony xperia which is bit bigger than your wish list but a good size. works really well. Easily viewable in daylight though not really in bright sunshine, fine under a sprayhood. Waterproof, unless you want to charge at the same time. Huge plus is having the excellent Opencpn AIS display :cool:

Did you get a Rasp Pi up and running? Works great with data from the Pi with a few cheap sensors EG barometer, thermometers & battery voltage.
 
I am in the process of relaunching after 5years ashore. My plotters are both operating very well but have old charts etc. In order to remedy this and to get ais I bought a bundle from London chart plotters. I got a really poor quality feeling tablet with doubtful battery life and a plastic bag to put it in and a mount with a set of impressive raster charts and an ais/wifi thing.

All of this cost me circa 200euros.

Separatly I bought a rugged waterproof phone with incredible battery life and memory...cubot King Kong 3.. opencpn and vector charts for the British isles and northern France and with a bicycle mount/bag from Aldi I now have a binacle mount for my phone. Bluetooth earphones let me take calls and listen to music and the charts /gps are totally protected and independent of the boat. What I must do next is set up the ais on the phone and it will be a really good combination for less than 3oo quid including dual SIM phone.
 
If it is intended, as the OP says, as “backup” for primary navigation systems I would definitely suggest (and it is what I have as backup):
(A) any decent tablet with integral GPS and a waterproof case (only used when tablet is in fact needed on deck), and
(B) mobile phone with GPS.
I happen to have all U.K. Admiralty Charts on both using Memory Map, as main navigation use is with Antares.
But if not in Scotland Navionics is probably an easier to use alternative.

Could probably buy a couple of spare tablets cheaper than one rugged one. But my iPad has lasted 5 years so far - in spite of a smashed screen when it literally blew away in a gale and smashed on the stone quayside.
 
The OP seems confused whether it's a backup or the preferred first thing he's going to look at.
I use my phone, but I don't call it a backup, I think of it more as a tool I use but don't rely on.
My HH GPS is a backup. It is rugged, waterproof and self contained. It will survive any problem I've ever had, or am likely to have.
It's actually quite hard to use a tablet singlehanded when your autopilot goes u/s.

Different people seem to use the tools in very different ways. The plotter or other device is only one tool, a part of your system for navigating from A to B. It might help to think about the whole system.
 
Planning on a tablet - lacks precision in my opinion.

You have a laptop running OpenCPN - this says to me your tablet might benefit from also running OpenCPN for consistency. First question is - does the tablet run OpenCPN ...or... do you use it as a remote monitor to run the laptop's OpenCPN +/- a RasPi's

You can take the laptop home. Passage plan to your hearts content and then revise those plans down below in the cabin and view them on screen with AIS overlay etc.

That means the tablet doesn't need GPS.

It does need WiFi (all tablets surely have).

In my opinion, you will want to charge as you sail. (Or maybe two tablets!). I think that is a challenge. But most tablets struggle to do lots of wifi etc with bright screen for a long time.


Pocket-sized, about 8inch screen
2 SD or MSD card slot Makes waterproofing harder on a rugged machine. Why do you want it? MicroSD is so tiny they are easy to loose. If you are using a VNC to the Laptop / Pi you don't need any major memory in the screen
3 Good multi-source GPS As I said above - consider using what you already have. Your phone has a GPS no doubt so if its as a contingency - you have one already... consider a suitable app for it
4 SIM card for phone Why? If you get a GPS tablet it will usually have a SIM usually. But presumably you already have a phone?
5 Wifi (for AIS) All tablets have WiFi
6 Decent memory for apps such as Ephemeris, Star Map, some music/books, etc. Don't use SD cards for Apps if you can possibly avoid it - they are slow and less reliable. BUT - I think the brain belongs below deck I've never been a music guy, so the idea of sailing with music is weird to me. I certainly couldn't read while sailing. Perhaps at anchor. But a waterproof bluetooth speaker from phone/laptop seems more functional to be honest.

Why pocket sized? Are you going to sail with it in your pocket? I think most people would sail with it mounted somewhere. I think that should be mounted and charging. I don't know any rugged machines that can charge and remain waterproof. I think there are some cases that can do that - but your starting point may be the case - then the tablet because sure as eggs are eggs if you buy a random cheap tablet there wont be a case that fits that lets you plug in and turn it on in the case.
 
Run a Huwaei 10.1 inch in a case fitted to it within a waterproof bag/case
this sits on the helm I run open CPN with intergrated GPS using Admirality charts from O Charts for the UK
Run main computer down below HDMI onto 24 inch screen running the same program
AIS with wifi to Tablet

No need to buy an expensive tablet ,
Back up, always 2 phones on board me and the lady GPS and local maps and Apps
2 hand held GPS Units on board and paper Maps of my crusing ground (with the abilty to read and plot and use thsoe Maps:D)
So unless the 7 Riders of Death descent upon the earth and start the End of Humanity I should be able to find my way :encouragement:
 
I don't know where you sail, but I'd say get a cheap tablet and use Navionics on it. I sail in Scotland and Greece and it all works fine. I also have Marine Navigator because it allows me to load the Antares charts and it can use the SD card to store vast amounts of data. It is fast enough and reliable enough for the job. I like to have the Ordnance Survey maps too, and Viewranger handles that well, with the maps on the SD card. (All of this is duplicated on my phone.)

The real brains of my system is a Laptop with SeaClear which sits below and drives instruments in the cockpit for the helm as well as picking up AIS,

I bluetooth routes etc between devices depending on where I do the planning - e.g., on the tablet in my bunk over my morning tea.

As my tablet is not the main navigation device I let it switch off its screen for most of the time on passage. (You may be able to do this anyway.) There's also no need for it to do any wifi or bluetooth during a passage. Mine, under these conditions, and using its internal GPS will give about 24 hours use without charging, which is longer than almost all of my passages. The laptop is always under charge from the boat's 12V system.

But, having described all this complexity, I should say that I know yachtmaster instructors who secretly do all their own nav on a phone with Navionics and nothing else.
 
Thanks for the suggestions and experiences.

I am happy with my standard nav kit of paper charts, laptop, small h/h GPS, AIS, chart plotter, and the archive deck log: all of which provide several independent streams of position input and recording. However, they are all located around the chart table, and within the scenario of a solo trip running into a patch of bad visibility or otherwise losing my clear perception of position, the objective is to find a device that could make it unnecessary for me to leave the tiller and work at the chart table. No radar BTW, and my favoured Toughcharts are difficult to use when steering and are passive re position.

Hence portability, and perhaps links to AIS on a well-regarded active chart system (e.g. OpenCPN/Navionics).

A couple of PMs have supported the idea of a standard tablet, e.g. Ipad or Samsung Galaxy, in a tough case. A standard tablet has masses of RAM and other storage, decent screen sizes, and seems capable of handling all the data needed . Apparently tablet nav programs will save the track, so that in the event of GPS disappearing, one has a last known position from which to work - but in real time, not when one updated on the deck log 30 minutes ago.

So ordinary tablet plus armoured case looks like the best piece of kit for contingency, active, position fixing - subject of course to the known vagaries and eccentricities of little chunks of electronics rushing around some 12000 miles above the sea surface.

Thanks again.


PS. At the last count I had 4 anchors on board, and some 250m of chain and rope just in case I need to stop and think...
 
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Thanks for the suggestions and experiences.

I am happy with my standard nav kit of paper charts, laptop, small h/h GPS, AIS, chart plotter, and the archive deck log: all of which provide several independent streams of position input and recording. However, they are all located around the chart table, and within the scenario of a solo trip running into a patch of bad visibility or otherwise losing my clear perception of position, the objective is to find a device that could make it unnecessary for me to leave the tiller and work at the chart table. No radar BTW, and my favoured Toughcharts are difficult to use when steering and are passive re position.

Hence portability, and perhaps links to AIS on a well-regarded active chart system (e.g. OpenCPN/Navionics).

A couple of PMs have supported the idea of a standard tablet, e.g. Ipad or Samsung Galaxy, in a tough case. A standard tablet has masses of RAM and other storage, decent screen sizes, and seems capable of handling all the data needed . Apparently tablet nav programs will save the track, so that in the event of GPS disappearing, one has a last known position from which to work - but in real time, not when one updated on the deck log 30 minutes ago.
.......

I think it would be interesting to run through how your methodology is going to stand up in a few different scenarios:

1) You realise you do not trust your tablet's GPS position, but you're unsure when it ceased to be valid.
2) Your tablet becomes unresponsive at a key moment
3) You have no reason to doubt the tablet but the indication from the depth sounder does not tally with the chart.
4) You make somesort of simple basic mistake, e.g. a waypoint entered wrongly.
ISTM that PhillM's incident showed that having multiple backup devices is no good if you don't have a rigorous method in place.
It's all easy while everything works as it should.
When things go wrong and you are tired, how do your methods get you reliably back on track?

Having sailed some OPB's where people are using such methods, I still think it's good to stop playing with the sails and tiller every hour/30 minutes/(according to circumstances) and put a cross on the chart and do a reality check.

I'm not really trying to criticise phones or tablets, but trying to look behind that, fundamental methods, what goes wrong, what makes the difference between a comedy moment and a fiasco or crisis?
 
I use a Lenovo Tab 8 Android mounted on a Rokk Midi which is attached to the bulkhead via a Rokk self adhesive mount. The suction cup was hopeless. I've attached a GoPro self adhesive mount to the tablet itself to tether it to the base in case it slips out of the jaws of the Midi clamp.

It is housed in nothing at all in most of the condition I sail in. If it gets rough / raining it goes in to an Overboard waterproof bag which fits in the Rokk clamp and is again tethered to the base. The screen is still touch sensitive whilst in the bag. I get about 10 hours continuous use on full brightness and yes, it is viewable in daylight.

This set up allows me to view the screen from the tiller in all weathers and was very handy when caught in fog recently.
 
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My only concern with tablets is the inability to show AIS via Navionics directly (leaving aside the sunlight viewing issues)but its a great back up to a chartplotter ,has its own power and can be backed up by a powerpack plus obviously usual charging via USB or sockets and when paired with the plotter a much more useful device given portability and screen size than say a handheld Garmin as a backup .
Don't think though I would be without the plotter but if the tablet mirrors the plotter screen and also has an independent capability it gives the flexibility of not being tied to the plotter location . Toughbook plotters always look quite pricey and a standard tablet in a case is probably fine unless you are out in extreme conditions
 
You are right to be rigorous and questioning but I went through all those in the Assumptions phase. And have done peer to peer review of the protocol with another (professionally qualified) forumite.

1) You realise you do not trust your tablet's GPS position, but you're unsure when it ceased to be valid.

Revert to last position of high confidence. In what plane pilots call VFR, I'd expect to correlate with depth, wind and wave direction, fog sound signals, any lights, RDF, DR position etc every 30 to 60 minutes. Deterioration from visual certainty means reducing the time interval and looking for secondary points of information. The more Venn circles or lines of position you can add, the greater the confidence level.

2) Your tablet becomes unresponsive at a key moment

Quick check on other systems. If common source of failure, then stop and think, or if VFR still active, then pilotage not navigation. Or park the boat.


3) You have no reason to doubt the tablet but the indication from the depth sounder does not tally with the chart.

If depth is a critical data correlation, then lead line (old diving weight and 15m of best string, kept in cockpit locker. Tide heights and times marked in chinagraph on cockpit status board.

4) You make somesort of simple basic mistake, e.g. a waypoint entered wrongly.

I don't have a automatic steering system via a plotter that uses waypoints. It's all manual. My knowledge of an entered waypoint is that it displays on the electronic chart. In theory I could use three separate systems of electronic charts, plus paper. That limits the degrees of freedom for making errors, especially if a waypoint ends up displaying on land or in the middle of Biscay. More of a planning issue than IRL, perhaps ?


ISTM that PhillM's incident showed that having multiple backup devices is no good if you don't have a rigorous method in place.

That's the aim. I have identified one particular scenario where my present kit might present a management difficulty, and adding a tablet means the data hitherto available only at the chart table becomes accessible to hand at the tiller. If that system fails (and I think that anyone would perceive it failing within a few minutes,) I revert to heaving-to or anchoring till the prob is resolved.

It's all easy while everything works as it should. When things go wrong and you are tired, how do your methods get you reliably back on track ?


I am not being facile about this. I have identified one scenario with a medium risk/high consequence value. Taken in conjunction with the ordinary sensible and experienced practice of seamanship, it seems to me that a tablet is the appropriate response.

I'd like to think that having worked and taught in the nuclear crisis industry for two decades, I would be familiar with fatigue recognition and management. I also remember the famed Admiralty instructions for dealing with a lee shore. "Don't get caught on a lee shore". Mitigation, mitigation, mitigation.
 
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In my hands (which may be poor hands) paper methods probably ten times more prone to silly errors than electronic methods. You don't "enter waypoints" you plonk them down exactly where you want them. I propagate routes to at least three, sometimes four devices - this can take up to five minutes of my time. I have, at a minimum one laptop, two android devices and (if I remember correctly) four handheld GPSs that can store all the details. I have had about half a dozen equipment failures in twelve years of sailing this way, and have never had two devices fail at once. When navigating with paper I have on many occasions put the cross in the wrong place - I guess I'm just a bit incompetent.
 
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