GPS hazard alert

[soares29]

Hi,

Anyone aware of ways to have hazard alert on portable gps, watch gps or cellphone ? Like an alarm when close to something specific like a rock/wreck/shoal ?
Thank you

[tkeithlu]

GPS does not of itself have a way to identify anything, since it communicates only with satellites. It would take a database that, for example, mapped the edges of a channel.

[tarian]

Originally Posted by soares29

Hi,

Anyone aware of ways to have hazard alert on portable gps, watch gps or cellphone ? Like an alarm when close to something specific like a rock/wreck/shoal ?
Thank you

you will need some sort of chart source or hazard data base to connect to the GPS to give you warnings , impossible without.
Try paper charts and mark your passage and you can then put waypoints into your GPS so you know were the hazards are when you approach.

[soares29]

Are you familiar with anchor alarms ? If out of the circle alarms... I would like something in the opposite.... if inside a specific circle alarms...
anyway thank you for the answer.

[soares29]

Originally Posted by tarian

you will need some sort of chart source or hazard data base to connect to the GPS to give you warnings , impossible without.

Try paper charts and mark your passage and you can then put waypoints into your GPS so you know were the hazards are when you approach.

Yes. Makes sense. Would be great that with some setup Navionics could do this....like for depth, etc...

[tarian]

Originally Posted by soares29

Are you familiar with anchor alarms ? If out of the circle alarms... I would like something in the opposite.... if inside a specific circle alarms...
anyway thank you for the answer.

You set an anchor alarm via an app which uses GPS to allow to set a range , which is in one position as your boat is anchored or moored , you are talking about an app that has a data of a particular chart with hazards then expecting the GPS (handheld) which do not have alarms on them to alert you , this is called a chart or chartplotter with correct charts connected to your GPS so that the data on the chart your movement through water and GPS all work together
so to think that to take the most important part out of the equation i.e charts and data does not happen, and frankly probably no market for such a think to be invented.
Like I said above , you can enter waypoints (longitude, latitude )onto a handheld GPS and track your movement and specifically have hazards as way points so you know you are approaching them , but this is the very basic of seamanship.

[Bill O]

As mentioned there are anchor proximity alarms and others.

In OpenCPN, there are off course settings in Watchdog that would trigger an alarm. If they were know hazards, one would set a course to avoid them and if you deviated off that course, then the course alarm would be useful if you deviated.


Bill O.

[conachair]

Opencpn watchdog cam also alert if near land >
https://opencpn.org/wiki/dokuwiki/do...landfall_alarm

[ranger58sb]

Originally Posted by soares29

Hi,

Anyone aware of ways to have hazard alert on portable gps, watch gps or cellphone ? Like an alarm when close to something specific like a rock/wreck/shoal ?
Thank you

ActiveCaptain will show your position as you approach one of their hazard markers. Not aware of a way to make that initiate an audible alarm, though (but also haven't looked). Nor do their markers cover every potential charted hazard.

A typical solution is to watch where you are, relative to what's around you, on a chart plotter

-Chris

[Moo]

GPS is just one method of measuring position and can't help you however many navigation software apps support this feature.

The smarter ones can read the vector charts and give you alerts based on hazards on your course. The more basic stuff like OpenCPN and TimeZero allow you to set boundaries and zones that will warn if you are off course and stray into them but you have to set those up manually.

I wrote a tutorial that demos some of that

tutorial that demos

some of this on Nobletec Timezero some time ago.

Otherwise read the docs on the OCPN watchdog plugin.

Cheers
Chris

[BeginnerBoater]

Originally Posted by soares29

Hi,

Anyone aware of ways to have hazard alert on portable gps, watch gps or cellphone ? Like an alarm when close to something specific like a rock/wreck/shoal ?
Thank you

That's exactly the same I've been looking for. Plotter with audio warnings. Regular plotters don't give warnings (at least not audible), you need to follow the screen and even make conclusions. Car navigation systems have had audible warnings since the very beginning, i.e. almost 20 years...

[AndyEss]

Originally Posted by BeginnerBoater

That's exactly the same I've been looking for. Plotter with audio warnings. Regular plotters don't give warnings (at least not audible), you need to follow the screen and even make conclusions. Car navigation systems have had audible warnings since the very beginning, i.e. almost 20 years...

Car navigation doesn’t have to consider datum changes. Boats respond to tide - a channel that is safe at high tide may be impassible at low tide. Car wrecks aren’t usually left on the road - sunken obstructions can come and go.

If as a new boater (Post #1) you believe that sailing a boat is the same as driving a car, let’s say I hope your learning curve is faster than most.