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-   -   Why Integrate the Autopilot ? (http://www.cruisersforum.com/forums/f13/why-integrate-the-autopilot-70649.html)

Sabbatical II 27-10-2011 12:14

Why Integrate the Autopilot ?
 
All the electronics manufacturers seem to be promoting totally integrated electronics packages for new fit ups. I can see some advantages and some disadvantages. The major disadvantage seems to me that one component failure may mean that you lose the functionality of every component in the system. My major concern is the autopilot. If the autopilot can't trim the sails then what advantage is it to have course changes etc programmed into the system?

Can anyone help me with one advantage of having the autopilot integrated?

Greg

Alecadi 27-10-2011 12:34

Re: Why integrate the autopilot?
 
Quote:

Originally Posted by Eleebana (Post 805303)
All the electronics manufacturers seem to be promoting totally integrated electronics packages for new fit ups. I can see some advantages and some disadvantages. The major disadvantage seems to me that one component failure may mean that you lose the functionality of every component in the system. My major concern is the autopilot. If the autopilot can't trim the sails then what advantage is it to have course changes etc programmed into the system?

Can anyone help me with one advantage of having the autopilot integrated?

Greg

the auto Pilot take the helm when you do the trim
That's one more hand on board
and doesn't sleep or drink...
I love mine
we call him Captain Ron...

colemj 27-10-2011 12:59

Re: Why integrate the autopilot?
 
It is very useful to have the autopilot integrated with the instruments so that it can steer to a set wind angle or to a GPS waypoint.

A networked instrument package will not be brought down in entirety because a single component fails. Only that component will be down. However, loss of functionality will occur - example: GPS receiver fails, so you lose SOG, COG, chartplotting, etc. However, that would also be the case if the GPS was stand-alone.

Mark

Vasco 27-10-2011 13:04

Re: Why integrate the autopilot?
 
With an integrated auto pilot your boat will stay on course when you press the "track" button even with a lot of leeway (sea conditions) or set (current). It automatically adjusts the heading continuously so that there is no cross track error.

CarlF 27-10-2011 13:31

Re: Why integrate the autopilot?
 
Start with a few harsh truths:

1. The idea of perfect integration is aspirational. It never works 100% and never will. There's always a missing software update, a $10 network connector that has an invisible crack, or too long a wire.

2. Most chart plotters simultaneously support three incompatible network standards on three different wires (NMEA 0183, NMEA 2000, and proprietary). Who are they kidding? :banghead:

3. If you put anything on the network from a different company then it will work even less well (ignore that NMEA 2000 was a "plug and play" standard" designed to allow precisely this mixing).

4. Your boat isn't a climate controlled network closet. My autopilot rate compass doesn't agree with my GPS compass reading because one is magnetic subject to the boat's changing magnetic field and the other is computed from an incredibly weak signal from space. If I feed both compass readings to the chart plotter it will show that I'm going in two directions at once - sort of.

Like most people I know, I point the bow of the boat in the direction I want to go and engage the autopilot. If I see a lobster pot ahead, I push starboard 10 degrees, wait 20 seconds and push port 10 degrees. When I get close to the next mark on my course I disengage the autopilot, point the bow in the direction of the next mark, then re-engage.

Works great :D

Carl

sailorboy1 27-10-2011 13:43

Re: Why integrate the autopilot?
 
I used to was think the integration was crazy and just got on course and set the autopilot. This of course met I had to check the course a lot and adjust my heading. On a longer passage with changes of current etc this happened a lot. It also of course met longer passage distance as my cross track went back and forth.

I finally read all my manual and started using the Track mode and it is great! It will sail to the mark WAY better I could ever hope to do myself. Get on course, set the GO TO, Track it to autopilot, trim the sails, relax and enjoy my sail more.

Vasco 27-10-2011 13:49

Re: Why integrate the autopilot?
 
Quote:

Originally Posted by CarlF (Post 805355)



4. Your boat isn't a climate controlled network closet. My autopilot rate compass doesn't agree with my GPS compass reading because one is magnetic subject to the boat's changing magnetic field and the other is computed from an incredibly weak signal from space. If I feed both compass readings to the chart plotter it will show that I'm going in two directions at once - sort of.

l

Your GPS has a compass in it?

CarlF 27-10-2011 14:02

Re: Why integrate the autopilot?
 
You're right of course - not a real compass but a calculated compass course from the GPS if the boat's moving.

You are also right that the integration of chart plotter and autopilot could adjust for cross track error from current -- if you are lucky enough to get them working. But it gives me the shivers that some boat coming at me is in command of an electronic "Captain Ron".

Carl

djmarchand 27-10-2011 14:05

Re: Why integrate the autopilot?
 
Greg:

There are three types of integration that come to mind: autopilot slaved to the chartplotter so it can follow a route; autopilot slaved to the wind indicator so it can keep a constant angle to the wind and the chartplotter display integrated and overlayed with the radar display.

Of these three I find the wind integration the least useful. I just set a course and if it needs to be adjusted (or the sails adjusted) for wind shifts then I do that. Letting the autopilot sail the boat hard on the wind is never easy, but by falling off about 5 degrees and setting a course rather than an angle to the wind works best.

Following a route is marginally useful. I use it on long open water passages where there is nothing possibly in the way. But for navigating through islands and passages I simply point the course pointer where I want to go by adjusting my autopilot heading.

Integrating the radar display with the chartplotter can be very useful but only at rare times. While rounding Sandy Hook, NJ in the dead of night in a medium rainstorm it was comforting to see where the bouys should be on the chartplotter and see where they actually were on the radar return (matched within 100 feet) even though I couldn't see them visually because of the rain.

So some integration is useful but some is not.

David

Sandero 27-10-2011 14:15

Re: Why integrate the autopilot?
 
I don't advise driving the auto pilot from a chart plotter. It becomes tempting to let the electronics do everything.

Perhaps a safer approach is to use a chart plotter to determine to course... or trim the sails to a desired course... but YOU program the pilot.

I've seen near head on collisions from vessels on reciprocal courses meeting mid way... dead on the rhumb line from the entry buoy to entry buoy and no one was on watch. This is made more possible by programing with a chart plotter driving the pilot.... they can get theb boat to steer a course as straight as an arrow.

Be careful.

sailorboy1 27-10-2011 14:16

Re: Why integrate the autopilot?
 
Quote:

Originally Posted by CarlF (Post 805372)
But it gives me the shivers that some boat coming at me is in command of an electronic "Captain Ron".

Carl


Not really an intergration thing, just as real if someone has set the autopilot and stopped playing attention.

Saw a power run into a bouy last year that I figured had done this. I also feel a lot of lobster/fishing boats do this while they are doing other "stuff" and when see them heading toward and no one at the wheel well...........

Vasco 27-10-2011 14:26

Re: Why integrate the autopilot?
 
Quote:

Originally Posted by CarlF (Post 805372)
You're right of course - not a real compass but a calculated compass course from the GPS if the boat's moving.

You are also right that the integration of chart plotter and autopilot could adjust for cross track error from current -- if you are lucky enough to get them working. But it gives me the shivers that some boat coming at me is in command of an electronic "Captain Ron".

Carl

I am somewhat a traditionalist when it comes to anything to do with electronics. I am very wary of relying on anything electronic. However the track function in an integrated system has won me over. I used it sparingly at first but gradually have come to use it whenever possible. It is amazing.

Case in point. We were sailing up the Jumentos, a group of small, low cays just north of Cuba with stretches open to the ocean (actually the Crooked Island Passage) between the cays. It was a beautiful sail, gusty, blowing to 30 knots, a beam reach. The course does not allow for much error as reefs and coral heads abound. The track function kept us right on course, at times heading up to 20 degrees off the true course. A buddy who was following me said that sometimes I looked like I was crabbing along. A great sail, right on course all the time. But I was thinking " Raymarine don't fail me now" all the time. :)

savoir 27-10-2011 14:39

Re: Why integrate the autopilot?
 
If you lose your GPS and/or your wind instruments, the autopilot will still work fairly well. It should still be able to steer to a compass course. If the fluxgate drops out soon after then you have a problem.

rusky 27-10-2011 14:55

Re: Why Integrate the Autopilot ?
 
I dont think it is good seamanship to integrate the autopilot with the plotter. I believe in using the sutopilot as soon as we are clear of the marina leads, and plot a course, but someone has to be on watch and tweak the auto if we are off course.

We all plot the straitest /quickest course to get from a to b. We have all had another vessel come close, seemingly with no one on watch - guess what, they have a wonderful integrated system they can trust enough to go below for a cuppa or whatever.

Secondly it maintains a mindset of trust and then,. when something goes wrong, sudden distrust in the electronics. That is not good seamanship.

If you need the auto to tack whilst you leave the cockpit to adjust sails, is that also not good common sense.

:viking:

colemj 27-10-2011 15:13

Re: Why Integrate the Autopilot ?
 
Why are some of you assuming because the autopilot is getting course instructions from the GPS that no one is watching and able to respond or tweak the pilot?

How is integration different than just setting the autopilot to a compass course and abandoning the helm/watch?

Integration has nothing to do with seamanship at all. And a mindset of trust of electronics also has nothing to do with seamanship any more than a mindset of trust in your rigging.

Mark


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