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Old 04-12-2015, 05:47   #1906
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Re: Feature Requests

There are a couple existing standard solutions to the MOB scenario presented. If the single watch person keeps a personal AIS beacon clipped to their life jacket then from the water they can raise a MOB alarm on OpenCPN via the shipboard AIS receiver. O will show the exact MOB position. This isn't cheap but not terribly expensive. I think one can purchase all the hardware for < $500US and much less than that if you use the SDR AIS solution. That seems like a pretty reasonable cost to save a life.

Has anyone made sure that MOB alert AIS messages are handled properly (e.g. don't remove a MOB AIS marker until user clears it)?

Another solution is use of DSC handheld by MOB. It has a big advantage over AIS in my view because the shipboard VHF can request the location of the MOB even if the MOB is unconscious so long as the MOB handheld is turned on and not underwater. Single watch stander should clip VHF to life jacket in a way that when inflated the handheld antenna will be out of the water. Granted many jackets make this harder than it should be. Leave the radio on all during the watch which favors Li rechargeable handhelds. Has anyone made sure that DSC alerts are shown by OpenCPN and maintained until cleared by user?
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Old 04-12-2015, 05:56   #1907
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Re: Feature Requests

Quote:
..personal AIS beacon clipped to their life jacket then from the water they can raise a MOB alarm on OpenCPN via the shipboard AIS receiver. O will show the exact MOB position. .. all the hardware for < $500 US and much less than that if you use the SDR AIS solution. That seems like a pretty reasonable cost to save a life.
Has anyone made sure that MOB alert AIS messages are handled properly (e.g. don't remove a MOB AIS marker until user clears it)?
When this was being implemented I believe it was confirmed to work properly.
I do not recall who tested it, but record is somewhere in the forum. There were several iterations with Bdcat.
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Old 04-12-2015, 06:01   #1908
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Re: Feature Requests

You forgot another solution which is very cheap compared to your others: Simply always wear a life belt attached to the boat.

Gerhard
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Old 04-12-2015, 06:46   #1909
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Re: Feature Requests

OpenCPN and DSC alert ? What about ?
Quote:
Gilletarom...
Two different types of alerts.
One is SART, which is a SearchAndRescueTransponder. The MMSI starts with 97..... This might be from a PLB on man overboard, for instance.
The other is a general "Distress" alert, coming from a specific vessel, presumably by crew activating a switch on the transponder. These are occasionally seen as false alerts, for testing.
Both are very rare, thankfully.
Dave
Could not find the notes during development. These should probably be put in the documentation more explicitly.
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Old 04-12-2015, 07:09   #1910
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Re: Feature Requests

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Originally Posted by CarCode View Post
You forgot another solution which is very cheap compared to your others: Simply always wear a life belt attached to the boat.

Gerhard
The benefit of having a way to alert off watch about a MOB is beneficial. For some crew it is the only way they can get a good sleep. So while a tether will prevent going overboard it probably doesn't give peace of mind to off watch crew. Well rested off watch crew creates a significant safety benefit during long passages.
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Old 04-12-2015, 07:26   #1911
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Re: Feature Requests

Found it

FS#802 - AIS Track own MOB AIS SART & Enter MMSI and chose an Action
http://willkamp.com/opencpn/flyspray/index.php?do=details&task_id=802&string


http://www.cruisersforum.com/forums/f13/raymarine-e80-ais-650-mcmurdo-ais-plb-mob-125035.html#post1526320

We did a full live test of the device in the middle of the Caribbean away from any other shipping. The C125 alarmed quickly with the same generic sound as all the other general alarms. I had to actively acknowledge to clear the alarm. The target then unfortunately looked just like any other ship - the usual triangle shape.

More Unique Icon Needed. (bdcat proposal is good!)
It seems a shame that they can program a more unique icon to this particular alert given its importance.

Different Audible Alert Needed
Would also be nice to have a slightly different audible alert to distinguish it from other alerts. When we use the auto pilot to sail to wind we can often be in situations where the wind shift alert goes off far too regularly. This numbs the person off duty to the alarm.
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Old 04-12-2015, 07:48   #1912
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Re: Feature Requests

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Originally Posted by transmitterdan View Post

Another solution is use of DSC handheld by MOB. It has a big advantage over AIS in my view because the shipboard VHF can request the location of the MOB even if the MOB is unconscious so long as the MOB handheld is turned on and not underwater. Single watch stander should clip VHF to life jacket in a way that when inflated the handheld antenna will be out of the water. Granted many jackets make this harder than it should be. Leave the radio on all during the watch which favors Li rechargeable handhelds. Has anyone made sure that DSC alerts are shown by OpenCPN and maintained until cleared by user?
We have used a HX850 for many years now and it is excellent for MOB use. Just to bring you up to date the new Standard Horizon HX870 will switch its self on and flash SOS light when it goes in the water. I am assuming that once switched on it will respond to position requests also. I haven't read the manual properly but it appears to generate NMEA sentences. Not useful when the radio is with a MOB but I am wondering if new or existing versions of the SH fixed VHF's will include NMEA sentence from a DSC - MOB from a portable.
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Old 04-12-2015, 07:55   #1913
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Re: Feature Requests

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Originally Posted by transmitterdan View Post
The benefit of having a way to alert off watch about a MOB is beneficial. For some crew it is the only way they can get a good sleep. So while a tether will prevent going overboard it probably doesn't give peace of mind to off watch crew. Well rested off watch crew creates a significant safety benefit during long passages.
Not true. Any inherent solution is far better than anything else which can fail.

Gerhard
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Old 04-12-2015, 08:18   #1914
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Re: Feature Requests

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Originally Posted by transmitterdan View Post

Has anyone made sure that MOB alert AIS messages are handled properly (e.g. don't remove a MOB AIS marker until user clears it)?
TDan
My experiences, ver 4.1.....?, from the summer before last is that a MOB alert can't be switched off in O. I spend half a day with a, false, alert from another boat until the distance, or SAR, cleared it. (I met the boat and they didn't answer VHF calls but eventually a SAR hunting them got in touch.)

Håkan
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Old 04-12-2015, 08:49   #1915
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Re: Feature Requests

Hakan, tracker?
Quote:
a MOB alert can't be switched off in O.
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Old 04-12-2015, 08:52   #1916
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Re: Feature Requests

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Originally Posted by CarCode View Post
You forgot another solution which is very cheap compared to your others: Simply always wear a life belt attached to the boat.

Gerhard
There was a well publicised case in the UK a couple of years ago when a well-equipped skipper fell overboard and was drowned. He had all the right equipment, life-jacket, tether, harness etc. But he went overboard near the bow and was towed along at 5-6 knots on his tether and was unable to save himself.

It was several, maybe ten minutes before the crew realised he had gone overboard. Had they realised much more quickly with the kind of alarm we're discussing here they might have been able to rescue him before he drowned.

Certainly we have re-thought the safety line arrangements on our boat and now I'm thinking about alarms as well.
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Old 04-12-2015, 09:28   #1917
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Re: Feature Requests

Rick...
re: Hakan, tracker?
Sorry, I don't understand?
Håkan
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Old 04-12-2015, 09:48   #1918
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Re: Feature Requests

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Originally Posted by hoolie View Post
Certainly we have re-thought the safety line arrangements on our boat and now I'm thinking about alarms as well.
Might be better to stay ashore then...

Gerhard
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Old 04-12-2015, 10:49   #1919
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Re: Feature Requests

Hakan if it doesnt work maybe we should put it in tracker? If you want i can enter it, but we should be sure and have some details. Maybe I should try to simulate?
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Old 04-12-2015, 11:09   #1920
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Re: Feature Requests

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Originally Posted by CarCode View Post
Might be better to stay ashore then...

Gerhard
You are always clipped to your jacklines? always?
I confess I am not. E.g. on a nice sunny afternoon I am not tethered.
When going down in the sail locker or engine compartment I am not. When doing something on the cabin top I am not. The boat is 6m / 20ft wide and I don't want to run a spider web across.


At night the one on watch always carries a Lowrance Link2 handheld VHF with GPS & DSC. However we can't make this a 24/7 rule without a bunch of spare batteries.
Plus during the day the off-watch (and the kids) roam around outside or inside and even our small cat is big enough that I am not always sure where everyone is.



A handheld VHF is not an automatic alert. Either the MOB needs to press the distress button to alert the boat VHF or the off-watch needs to query the position of the handheld. I doubt that someone in panic mode will find the right menu items to do a position query.
Even if this works out OK this query will just return the numeric position but will not simply drop a MOB marker on the OpenCPN chart.


These Bluetooth beacons have a battery life of a year or more. They are small enough that we can make every person onboard wear one 24/7.
I will order a handfull and play around with them. I would love to see them integrated into OpenCPN but even if not these are helpful items to have.
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