autopilots

[koliver]

When set to follow a multiple-waypoint route, my (Simrad) AP will change course automatically, as long as the course change doesn't exceed something like 15 degrees. It also has a follow the bottom contour mode, which can be great for fishing, in which it seems quite willing to make significant course changes without user confirmation.

As Dave mentioned... worrying.

Just as you are out on the side deck showing off the fish your AP has helped you to catch, to the friend who has come up close alongside for the viewing, the AP automatically turns 10 degrees to Port and suddenly you are in trouble.

 

[CaptTom]

Question is... do you trust your thousand of dollars boat at a $20 component? Because that's the question..

The answer is No. I trust nothing. I do put some faith every component in the AP system; the GPS, the brain, the pump, all the connections, fittings, etc. Some of which cost less than $20. But I am always prepared for any one of them to fail.

The AP is a convenience. The remote is little more than a toy. I'll get much more than $20 worth of enjoyment out of it. When it fails, I'll buy another. If I start to really depend on it, I'll buy a spare.

 

[markpierce]

Trust me not to hit you hard? (Not using Otto here.)



For me, the auto-pilot allows more situational awareness, as in keeping 360-degree observation rather than working to maintain a particular course.

 

[BandB]

As Dave mentioned... worrying.

Just as you are out on the side deck showing off the fish your AP has helped you to catch, to the friend who has come up close alongside for the viewing, the AP automatically turns 10 degrees to Port and suddenly you are in trouble.

To me that's just a wrong use of the A/P. It's a tool to assist you but not replace you.

 

[dhays]

To me that's just a wrong use of the A/P. It's a tool to assist you but not replace you.

I think it is simply an example. Just imagine leaving the Pilothouse to lean over the rail to check the hull, look behind, or check out the porpoise keeping pace. Any situation where you, crew, or guest are doing something where they don't expect a sudden course change is not the time for the AP to initiate a course change without an acknowledgment from the person in command.

 

[twistedtree]

Twistedtree,

I agree with you with one exception. I have a Garmin chartplotter, a Raymarine chartplotter, Coastal Explorer and a Raymarine EVO autopilot all tied to a NMEA2000 network. I can't get the autopilot to follow a course because the Raymarine and Garmin chartplotters are always transmitting autopilot NMEA 2000 PGNs with no data in them confusing the EVO autopilot when you tell it to follow a route from Coastal Explorer. If I turn off both chartplotters it works fine. If I turn off one or the other chartplotter I can send a route to the autopilot from the other. Kind of pain but I don't tell the AP to follow routes very often.

Tom

That sounds like the Raymarine pilot has no provision for doing data source selection. It should be able to pick which device to listen to, then only listen to that one even though the others are still talking. It's a fundamental requirement in N2K when you have more than one of any give device on the network. I've seen lots of products that don't do it well, and I only know of one product that doesn't do it at all and that's the AMEC NK-80 N2K to 0183 converter. Maybe now I know of two such products.

So the Ray pilot has no means to select which nav device it should listen to?

 

[twistedtree]

Within the Nav mode there are 2 formats. In the chart plotter, the message can either be correction of bearing to destination or cross track error correction. The correction of error means that as the boat is pushed off course (by current as an example), the chart plotter adjusts the bearing to the target. This yields a curve versus a straight line over the course of the navigation. In cross track error correction, the plotter steers the boat back to the original heading line. The course resembles a straight line.

Ted

Do you know which sentences or PGNs that's cover in? My understanding has been that it's totally up to the pilot to decide what to do with the info coming from the plotter. Indeed, the plotter sends two fundamental pieces of data; distance and bearing to waypoint, and cross track error. My pilot has a nav feature similar to yours where it will ignore cross track error and just keep aiming the boat at the waypoint, exactly as you describe. But I'm not aware of different data coming from the plotter to do that. But hey, you learn something new every day.

 

[twistedtree]

Thanks, haven't used the newer Simrads, but the old ones seemed to alway beep....just one of those things as much of my running commercial boats was inland or in the search pattern mode.

And memory....

I had a feeling sooner or later they would all have the option...but I figured it would be an option of auto turn or alert....just a feature easy enough to incorporate with advanced electronics.

The Furuno NavPilots beep, but only to tell you the waypoint changed. It then follows the change regardless. It might be possible to disable that, but I haven't tried.

 

[North Baltic sea]

came to my mind to add one case where I would not want to be without AP.


The fog, the AP gives you the opportunity monitors the radar and looking out. do not have to follow the compass and think to stay the course.

 

[tpbrady]

Twisted Tree,

You are correct, there is no way to do data source selection unless you use all Raymarine products. I brought this up on the Raymarine support forum and Raymarine added this to the feature enhancement list. I don't view it as an enhancement. To me its pure logic. Picking data sources should not be vendor specific.

Tom

 

[ranger58sb]

Can't say for all...but no boat autopilot I have used turns the boat automatically at a waypoint until you tell it to. I can't remember if they do turn in patterns automatically, but not just following a chartplotter route

They start beeping at the waypoint proximity alarm distance (I think), and when you press the proper button, it will turn off the last heading to the new required to obtain the desired track to the next waypoint.

We don't use predetermined routes very often, but I think our NavPilot automatically turns toward next waypoint, if it's been set to follow a route...

Don't remember beeps, but that's more a function of memory or lack thereof (mine)...

-Chris

 

[psneeld]

Wonder if the autopilot designers recently were anticipating the autorouting software.


Still hard for me to believe that these pilots that auto switch don't have a disable and just warn function.....or another function that only tracks but doesn't auto turn.


Oh well.....tech starting to pass me by .......though I really don't have an issue with auto turning.


After all, we are supposed to know where we are and aware of our surroundings. Plus as often as a danger lies in an unexpected turn, it lies dead ahead to.

 

[RT Firefly]

Greetings,
I haven't re-read this thread all the way through again BUT one of the issues about programing an autopilot is using navigational buoys as waypoints in that the AP may take one exactly to the buoy thus causing a collision with said buoy if one isn't paying strict attention.

 

[sunchaser]

Just had the latest and greatest AP from Furuno installed. When in the Nav mode, it's ability to follow an active route or go to a point is so much better than the still in place AP 20. But our desires reside in normally using it in the Auto mode even when following an active course. On longer, clear weather and no traffic legs the Nav mode is used, but as oft noted above with a good set of eyes.

In the often visibly challenged and under radar legs we never are in the Nav mode.

 

[CaptTom]

one of the issues about programing an autopilot is using navigational buoys as waypoints in that the AP may take one exactly to the buoy thus causing a collision with said buoy if one isn't paying strict attention.

I can attest to this. Used the "dodge" function, or even easier, disengaged than re-engaged the AP, a lot when I started following old routes I'd programmed before I had an AP.

Late last season I discovered that my MFD can run a route "offset" a selected distance to the right or left. I can't wait to try it.

Ideally, you can draw your course line down the middle of the channel, then run it offset to starboard so you stay on "your" side.

If you've already put in waypoints for each buoy on a coastal route, you can offset some distance to the seaward side, and usually be OK as long as the hazards are on the shoreward side.

 

[koliver]

Just had the latest and greatest AP from Furuno installed. When in the Nav mode, it's ability to follow an active route or go to a point is so much better than the still in place AP 20. But our desires reside in normally using it in the Auto mode even when following an active course. On longer, clear weather and no traffic legs the Nav mode is used, but as oft noted above with a good set of eyes.

In the often visibly challenged and under radar legs we never are in the Nav mode.

Tom: Congats on the upgrade. Does the new Furuno correct cross-track error in a better way than the old one?

My Raymarine will suddenly, with no warning, make a 10 degree turn, follow the corrective track until XTE reduces to 0, then again without warning, make another 10 deg turn back to the original track.

So, like Tom, I don't let the Nav mode run the boat when there is traffic, and never unsupervised.

 

[Ski in NC]

My old skool AP35 holds better in Auto than in Nav. In Nav it wiggles around some trying to minimize Xtrac error. In fact I have not used Nav in years. I don't even use waypoints anymore. I just extend my heading line on the laptop Coastal Explorer til it aims at where I want to go. Then tweak AP as needed. I've got to be at the helm anyway as a lookout and it gives me something to do.

 

[O C Diver]

Do you know which sentences or PGNs that's cover in? My understanding has been that it's totally up to the pilot to decide what to do with the info coming from the plotter. Indeed, the plotter sends two fundamental pieces of data; distance and bearing to waypoint, and cross track error. My pilot has a nav feature similar to yours where it will ignore cross track error and just keep aiming the boat at the waypoint, exactly as you describe. But I'm not aware of different data coming from the plotter to do that. But hey, you learn something new every day.

You are probably right that it's in the pilot. The last time I used bearing to target as opposed to cross track error, was with my Furuno LC 90 loran. My recollection was that the navigation format was charged in the loran not the pilot, but that was decades ago. At least I think it was on the loran.

Ted

 

[twistedtree]

Tom: Congats on the upgrade. Does the new Furuno correct cross-track error in a better way than the old one?

My Raymarine will suddenly, with no warning, make a 10 degree turn, follow the corrective track until XTE reduces to 0, then again without warning, make another 10 deg turn back to the original track.

So, like Tom, I don't let the Nav mode run the boat when there is traffic, and never unsupervised.

Tom and I have the same Furuno pilot. In Nav mode mine makes course adjustments of a couple of degrees to stay on track. I haven't paid a ton of attention to it, but I'd guess it's typically within 30' of the track line, probably more like 10-15'

When I find Nav mode results in too much back and forth is when there is highly variable current like whirlpools and other turbulence. The boat gets tossed around and the pilot lets it happen until the XTE gets too high, then does a larger correction to get back on course. In those situations I usually switch to Auto mode while passing through the turbulence. You need to manually compensate for any side current, but it generally holds a more stable course. Then I go right back to nav mode back once in more steady water. It's worth noting that when there is a steady cross current, the NavPilot figures it out pretty quickly and steers the boat with an appropriate heading offset to compensate, while at the same time staying on track. It takes it maybe 30-60 seconds to figure things out, but then goes right back to tracking really well. The only time it gets sloppy is when the cross currents are changing rapidly as in turbulence.

 

[sunchaser]

Tom: Congats on the upgrade. Does the new Furuno correct cross-track error in a better way than the old one?

My Raymarine will suddenly, with no warning, make a 10 degree turn, follow the corrective track until XTE reduces to 0, then again without warning, make another 10 deg turn back to the original track.

So, like Tom, I don't let the Nav mode run the boat when there is traffic, and never unsupervised.

Keith

Peter pretty well summarized it in post 49. I've this next cruising season to learn more, but in a gale in December the ability to follow an active course from Furuno charting systems proved much better than the AP 20 with input from the same systems - Trident and NN3.

 

[High Wire]

My Raymarine will suddenly, with no warning, make a 10 degree turn, follow the corrective track until XTE reduces to 0, then again without warning, make another 10 deg turn back to the original track.

So, like Tom, I don't let the Nav mode run the boat when there is traffic, and never unsupervised.

My RM ST6001 does similar. In Track Mode it will drift to one side 90 ft then make a 20 degree turn to get back on track, smooth or rough water. I can't depend on Track mode in the ICW. Normal Auto mode is much smoother.

 

[dhays]

My RM ST6001 does similar. In Track Mode it will drift to one side 90 ft then make a 20 degree turn to get back on track, smooth or rough water. I can't depend on Track mode in the ICW. Normal Auto mode is much smoother.

I have the same AP (or at least the same control head) but never have this problem. My AP does a great job of holding a track, even through the tides rips and currents of the Narrows. The current can swing the bow 20 degrees and the AP will bring it back on course calmly and gradually bring us back to the track. It may be that the behavior you are experiencing is related to your AP settings?

 

[High Wire]

I have the same AP (or at least the same control head) but never have this problem. My AP does a great job of holding a track, even through the tides rips and currents of the Narrows. The current can swing the bow 20 degrees and the AP will bring it back on course calmly and gradually bring us back to the track. It may be that the behavior you are experiencing is related to your AP settings?

I have not found anything in the manual that allows for deadband adjustment. Next time out I'll do a full seatrial calibration. It may be there just invisible to the user.