Anchor Alarms?

[Wotname]

Originally Posted by estarzinger

...............
In the big picture I am annoyed by (what I think is) the 'safety gear" fallacy (and 'fear based' marketing/assessments). I think it is a poor decision making process, and does the community a dis-service. (really you should tether up and clip on EVERYTIME you go on deck by this same logic). Specifically re anchor alarms, I disagree with the perspective that 'everyone should use one, why every would you not, you must be stupid not to'. I personally think there are very good reasons for me not to 'every day', as there are good risk/value reasons for me not to carry a defibrillator, and for me not to clip in every time I go on deck. If you want to do these things, perfect. But do realize I have tested almost all the available gear, and reached a (I think) thoughtful risk/value conclusion for me and my approach to cruising.

+1 x 10 (to the "n"th).

[estarzinger]

Originally Posted by Wotname

After 6 pages it might be a good time to revisit post #6 (Alan Mighty). The app. he mentioned did appear to cover all requirements (except it requires an Android device).

Actually one of the reasons for false positives with phone/pad apps is that the accuracy/stability of the gps signals INSIDE boats is lower than outside, in some boats (particularly ones with carbon or metal in the skin or frames) much lower. So the gps position can randomly wander +100m, which can of course set off anchor alarms. This is obviously boat specific/dependent. But that app does not 'solve' it.

Yes, you could solve this with an external gps for the phone/pad.

[nigel1]

Originally Posted by estarzinger

The vesper is nice kit but as an anchor alarm it only can 'drop' the anchor where the boat is. It does not have the capability (unless its been added since I updated my firmware) to place it's anchor waypoint where the anchor actually is (as some of the iphone apps do). This will lead to false positive alarms. Also if I want to see 'the cloud' of track points in relation to the land detail, I use the plotter rather than the vesper.

You can in theory activate the vesper, while you are lowering the anchor; but #1 this is not very practical double handed unless the unit is mounted at the helm (ours is not, it is mounted in the nav station, and that is a whole another discussion) and not very practical at all single handed (as I have been the past few years), and #2 even if you do that you probably still don't always get the anchor way point where the anchor actually is because if it is at all windy you will be moving as you lower the anchor and even once the anchor hits the bottom that is not necessarily where it will set. The anchor can very easily end up set 50' away from where you were lowering it down.

That would be one feature I would like to have on the Vesper, the ability to place your own estimation of the anchor position.

Like you Evans, I sail a lot single handed, and setting the anchor alarm is a real hit and miss affair.
Have anchor made ready to let go, and Vesper set to the anchor alarm set page.
Approach anchor position, stop the boat, jump down companion way, press button on the Vesper
Jump back out of companionway
Move forward as quickly as possible
Let go anchor
Set Anchor

Still, it is better than nothing I believe, but it would be nice to place own waypoint on the display.

[transmitterdan]

Originally Posted by tedsherrin

I'm aware of what 'apps' stands for thanks!

I'm glad you can put your faith in it. Good for you.

Me, I'll stick to my chart plotter alarm and external GPS antenna. So far it's never failed me. During the day, I've now tried my wife's ipad as well as mine and my iPhone 4s. As soon as I pull the sim, I loose the ability of tracking. Perhaps it's the Navionics software.. But regardless, I'll stick with the chart plotter.

For the rest of us with iPhones, they all have GPS that works just fine without cell service. The iPads without cell capability do not have GPS capability at all. Many Android tablets have GPS even without cell capability.

Ted's experience is a one off or something else is wrong. Don't let his experience put you off the iPhone or iPad with cell feature. They work just fine and have accurate GPS that is NOT dependent on cell service. They can use cell service to more quickly find their position but that's all. Also, if you are indoors they get an approximate position from cell when the GPS receiver can't see the sky.

[monte]

Again, I'm very happy with anchor watch on the iPad, iPhone 4 and iPhone 5. Also the anchor can be placed after anchoring if you aren't confident it will be accurate in 40' of water in 30K wind as you try press the button from the bow, which is reasonable. While backing down, set the range for 200' and place the anchor directly ahead so the boat is on the range ring. It's really simple, it works and the alarm will only go off if outside the range ring
As far as accuracy...yes I am sitting about 10ft from that dock >

[Palarran]

Quote:
Originally Posted by Palarran
Evans,
If the alarm goes off it's because you set it wrong or moved.

Well, perhaps I can learn something. Say you are anchoring in 30kts in 40' of water. How do you get the anchor way point to be actually where the anchor sets - or even within 50' of it?I have never been able to do that (even with the phone/pad apps I can take right to the bow), as the boat moves as I am lowering the anchor, and the anchor moves before it is set. I personally think there are clearly better alarm feature sets/software available today than the vesper.

I'm sorry but I used the word "you" as to whoever is operating the unit. But is the statement wrong? Are there other reasons the alarm would go off? To answer your question, with the Vesper it wouldn't be easy to set it exactly on the anchor. The distance as you know is going to be between your anchor drop point and the unit if your using the internal alarm. With Palarran that's about 30', which IMO is not that far and only causes a problem when you rotate more then 90 degrees.


Ours is located at the helm, which is probably where it should be, and is easy to coordinate with lowering the anchor.

First, how can you see it at the helm if you are under autopilot? Do you sit back there while under autopilot? I don't understand this question. I see it because usually I or someone is sitting in the helm chair. Second, this would not help me much single handed, But third, even double handed, as I said, that is another discussion. On Hawk I don't mount such gear at the helm. They go under the hard dodger both to protect them from weather/uv damage and because that is where we sit under autopilot, which is most of the time. I see, the reason we can see it is our helm is under a hard top. So I find your 'should be' a bit narrow decision making (yes purely for the anchor alarm but no for the ais and durability) at least for the way I equip and use Hawk. Fair enough




Really I've seen over a hundred boats drag anchor so far but none have ended up on the rocks or a beach.

Well, that simple observational fact SHOULD effect your thinking here about the risk/value. You'd have to explain why to me because I don't get it.

I might also just say you gave Anne a hard time, but your posts have a similar tone of preaching 'you set it wrong', 'it should be', 'I don't understand the mentality'. I posted 4 words in regards to Anne's, have reread them, and still think the same so I guess I'm just an ass. But I really feel you like calling the kettle black.

[Alan Mighty]

Seems a lot about anchor alarms has been lost in smoke and noise.

Let me try a real example:

I've anchored s/v Led Myne in a sandy/mud bottom at the Seagate Anchorage (quaint name; it's just off the Seagate factory in Penang, sheltered from the W by Pulau Pinang and from the E by Pulau Jerejak).

I'm going to dinghy ashore, leave the dinghy tied up in the care of a smiling local I only met yesterday and then make my way to find the best food and sights that Penang offers.

I happen to have two Android devices that happen to deliver 500 hours of standby time (no lie ... read a US-based review on Ars Technica)

Both have an anchor alarm app (Anchor Alert, as mentioned in post #6 in this thread). I will leave one in the engine compartment (it views the GPS + GLONASS satellites without too much trouble through one layer of GRP and it would be v hard for a petty thief to find and remove). The other Android device is in my pocket.

Deal is:

1. If Led Myne drags anchor or is dragged away by unimaginable forces (such as confederates of the smiling local), the SlimJim Anchor Alert app on Android device #1 will send an SMS to the Android device #2 in my backpack.

2. If I get lost in my land excursion or find a taxi driver who doesn't understand my few mispronounced words of Malay, the SlimJim Anchor Alert app on Android device #2 will guide me and the taxi driver back to the Seagate Anchorage.

3. Each Android device has a "find my phone" app. So if unimaginable force did remove Led Myne, I could point the local constabulary to the right place to recover Led Myne as long as I do it within 500 hours (if I had wired Android device #1 to boat power, I'd have more than 500 hours).

So it doesn't matter how egotistical I am, how good and experienced I am at sailing, or the sensitivity of my anus. And it doesn't matter whether I have the best Vesper or Vespa or whatever equipment in the cockpit or under a sprayhood.

As long as both Android devices see the satellites and both have cellphone service, I have up to 500 hours of shore leave. And a fair chance of recovering Led Myne, even if stolen.

Al

[monte]

Yes ted, your iPhone is special

[estarzinger]

Originally Posted by Palarran

>>The distance as you know is going to be between your anchor drop point and the unit if your using the internal alarm. With Palarran that's about 30', which IMO is not that far and only causes a problem when you rotate more then 90 degrees.

No, you miss my point, the distance i was talking about is going to be between your drop point and however far the boat drifts before the anchor hits the bottom plus however far the anchor moves before it sets.

Even with the apps where you can manually move the anchor waypoints, there are opportunities to get it wrong. Just one for example, is if you put out 150' of chain, and thus think you are 150' (roughly) from the anchor, but you did not lay it out in a perfectly straight line and the chain snags under a rock . . . You may only be 75' from your anchor even after the set


>>Are there other reasons the alarm would go off?


Well if you have inaccurate anchor location or the boat position, or set the alarm circle too tight, you may get false positives.

With the vesper/plotter it is primarily placing the anchor waypoint "inaccurately".

With the iPhone/pad apps, additionally is the decreased GPS accuracy inside my boat. I can get a 100m GPS position wandering. This is boat dependent, and my boat is a better faraday cage than most boats, so it is probably a bigger problem for me than most, but still something to consider on any boat.

I only set an alarm in "difficult anchoring" situations. I would say I get an alarm going off about half the times, and to date those have been 100% false positives (eg I have not dragged).

......

[Paul L]

I don't see the neccesity to strive for great accuracy on the anchor alarm. Set the circle larger and you will get very few false alarms. If your innate sense catches a drag earlier, then great. If not the alarm will catch it a few minutes latter. The alarms like the Vesper are just a low cost - in power and setting effort - tool.

[ranger58sb]

Originally Posted by MarkJ

My ipad one thats useless is called "Anchor Watch"... But it doesnt.

Originally Posted by monte

The best anchor alarm I have used is anchor watch. It works on iPad and iPhones. I have tried all the iPhone and iPad apps.
Attachment 88372
Here is a screen shot. If your device gas an internet connection it automatically overlays google earth as soon as it is turned on. Very handy for seeing actual distances to hazards, shallow water.

Originally Posted by Kenomac

I think I tested all the anchor alarm apps last month for my "Anchors are a drag" thread. Had the best luck using INavx chartplotter app on my ipad because it also provided a history, and "Anchor Watch/SMS" on my Samsung G4 android phone. The 5-6 others tested worked well, but these two were a little better.

Originally Posted by monte

Again, I'm very happy with anchor watch on the iPad, iPhone 4 and iPhone 5. Also the anchor can be placed after anchoring if you aren't confident it will be accurate in 40' of water in 30K wind as you try press the button from the bow, which is reasonable. While backing down, set the range for 200' and place the anchor directly ahead so the boat is on the range ring. It's really simple, it works and the alarm will only go off if outside the range ring
As far as accuracy...yes I am sitting about 10ft from that dock >
Attachment 88517

Are these all the same "Anchor Watch" ?? Who's the developer? What's power consumption like?

And/or is there an Android version? I see at least 5 Android apps named "Anchor Watch" (not counting the various free/paid versions) by different developers...

The overlay features as in Monte's attachments look interesting.

-Chris

[monte]

This is the one I use
http://lukassen.wordpress.com/luky-soft/anchor-watch/
I use the iPhone app on the iPhone and iPad, I haven't downloaded the iPad specific one as the iPhone one works fine on the iPad

[ranger58sb]

Originally Posted by monte

This is the one I use
Anchor Watch | Lukassen's Blog
I use the iPhone app on the iPhone and iPad, I haven't downloaded the iPad specific one as the iPhone one works fine on the iPad

Thanks for clarification. Apparently no Android version; and that's not one of the several Android apps with the same name...

-Chris

[noelex 77]

I have not used the anchor alarm apps much but I-Drifter XL seems the best to me. I presume with a name like that it is IPad/phone only.

[sailorboy1]

Originally Posted by noelex 77

I have not used the anchor alarm apps much but I-Drifter XL seems the best to me. I presume with a name like that it is IPad/phone only.

I didn't find it on an app search