Auto routing

[DrissZougari]

You can Plot your courses however, you should not expect your AP to take between two real beacons on the water due to GPS accuracy and beacons that are moved around to clear sandbars.

 

[rsn48]

I don't mean this in a machos way like "I don't need no stinking auto route," but more I don't get the point of it - at least for our area. Let's say you are going from Coupeville to Walsh Cove on West Redonda Island, it seems to me to be pretty straight forward. And the only challenge, Deception Pass or going past La Conner, heading north. And that, not much of a challenge. Even if you overnight somewhere, it most likely be on the BC coast, like Pender Harbour or the like. By the way, if you haven't stayed, I recommend the Texada Boat Club, a nice little spot and protected - and cheap.

 

[BDofMSP]

You can Plot your courses however, you should not expect your AP to take between two real beacons on the water due to GPS accuracy and beacons that are moved around to clear sandbars.

I think I understand your point. I wouldn't count on my autopilot to keep my route in a marked channel - I'd be hand steering that. I'm talking about open water navigation.

 

[caltexflanc]

I've tried auto routing a few times and just couldn't bond with the idea. Leaving aside issue of whether it's reliable (it has to be - it uses the same base data as it gives me if I were to manually route), setting a route is part of my process of trip planning. For me, auto routing makes the trip all about the destination and not enough about the journey.

Peter

This sums up my feelings as well. Plus there are often pieces of local knowledge not incorporated into the charts, even those updated weekly to the LNMs; could be something as simple as dredging or bridge issues or reported shoaling.

 

[BDofMSP]

This sums up my feelings as well. Plus there are often pieces of local knowledge not incorporated into the charts, even those updated weekly to the LNMs; could be something as simple as dredging or bridge issues or reported shoaling.

I don't understand what that has to do with auto routing. That information isn't on the plotter whether you're doing it manually or automatically. If the argument is that you shouldn't ONLY rely on depth to determine your route, then yes of course. You are always responsible to review the route and make sure it doesn't conflict with LNM info etc. That's true for manual routes too.

BD

 

[caltexflanc]

That information isn't on the plotter whether you're doing it manually or automatically.

That's exactly my point. Or one of them at least. Maybe I did a poor job of making it.

 

[markpierce]

Wouldn't trust it. There are too many changing variables to trust a computer.

 

[twistedtree]

I think there are several things getting munged together here that make it very confusing.


The original question was about auto routing, which is a feature where by the chart plotter creates a point to point route connecting a start and finish destination. The chart plotter in theory sorts out the best route taking into consideration water depths, obstructions, currents, etc. It's the same thing you can do manually on any chart plotter.


Once you have a route, there are several things you can do with it, but they are independent of HOW the route was created.


First is that most chart plotters will let you set a start time, or alternately an arrival time, and the chart plotter will figure out when you will reach each way point along the way. You tell it your cruise speed, and the better route planners will also factor in expected currents. This is the feature that lets you plan arrival at bridges for scheduled opening, estimate your destination ETA, or figure out when you need to leave. The important thing for this discussion is that this really has nothing to do with auto routing. It or at least it's not dependent on auto routing. The route can be created manually or automatically. It doesn't matter.


Second is an auto pilot's "Nav" mode. Auto pilots universally have two modes of operation. One is "Auto" where it simply steers to a heading, or ever and ever, until you tell it to do something different. You can "manually" follow a chart plotter route by changing the AP heading at each way point in the route. Again, this is completely independent of how that route was created, or if you are even following a charted route.


The second universal autopilot operating mode is "Nav" where the AP will follow the chart plotter's active route. The AP steers the boat to place it on the route's track line. It is following the track line, NOT steering towards the next waypoint. This is a very important distinction to understand, and can create big surprises if misunderstood. The problem occurs if yuo are located off the track line, and you activate Nav mode. The AP will steer you back to the track line, not towards the waypoint, and this can lead to abrupt and unexpected course changes.


When the boat gets within range of a waypoint (the arrival circle), it will initiate a turn to pickup the next track line segment. All APs alert when such a turn needs to be made. Most can be configured to alert and initiate the turn, or to alert and wait for confirmation before initiating the turn. Each can get you into trouble, or save your bacon, depending on the situation. And neither is a problem if you are keeping a watch. If you aren't keeping a good watch, don't blame you AP. The problem is in the mirror.


But getting back to auto routing, none of these AP steering modes or issues really have anything to do uniquely with auto routes. Once again it doesn't matter whether you or a computer created the route, the AP will follow it the same either way.


So statements like "I love auto routing because it tells me when I will arrive at a bridge" is kind of nonsensical. Having a route enables that feature. It is not unique to an auto route.


And similarly, saying that I like auto routing because my AP steers the way doesn't make sense either. An AP can steer any route you give it, regardless of who or what created it.

 

[BDofMSP]

Thank you, Twisted. Much better said than I have been. The auto generated route takes into consideration all of the information that is available on the chart. It's up to the user to review it against any new or local information they may have (such as LNM or reports of shoaling). Following it blindly is irresponsible, but using it as the foundation is simply saving you the work of creating it.

If people are arguing that you shouldn't use a course plotted on a plotter by any means, that's something completely different. I haven't heard that directly but some comments sound like that.

 

[oscar]

With vector charts obstructions often don't show until you zoom in.

There are several off shore navy aircraft towers on the east coast, and we're talking WELL off shore where one does NOT expect any solid object. I happened to be looking at a paper chart and notice one ahead of me..... I had to zoom down to the 4 mile scale before it showed up on my Raymarine plotter. I would have been close enough to hit it at about 3 am. Things that go Boom in the night.

No, I don't use auto route. I look at every inch of it.

 

[Peter B]

Oops. Doesn't belong in power systems. Shouldn't make new posts on the phone. Maybe the mods can move it?

Moved to Electronics/navigation section as requested.

 

[Portage_Bay]

Twisted you put it very well. BD you make good points. Since starting this thread and following it down it's divergent paths I've got a better understanding of why some like auto routing.

I am not one, nor will I likely be. Mvweebles gave a good opinion up thread I agree with. Planning routes is part of the joy in voyage planning. I don't want to let automation take that from me

Another thing to consider is that good route planning is more than the hard data of tides, currents, depths and the positions of nav aids. It's also experience, judgement and local knowledge which automation cannot replace.

For those with considerable experience why let automation make your decisions? For those without much experience how will you gain said experience if you let automation do the work?

That said if your planning tool is a plotter on an MFD then I can understand why you would let automation do the work. They are at best cumbersome to enter and edit waypoints. I much prefer to do my planning on a laptop with a 15" screen running straight forward easy to use software.

 

[catalinajack]

Portage, with respect, using automation is not letting it make the decisions. It is merely a starting point, a suggestion to be verified and modified based on experience and local knowledge, that is, if one has local knowledge. I do not have time nor would I enjoy in the least plotting 100, 200 waypoints or more manually every evening on a long cruise. I'd rather relax, have a brew and enjoy a good meal. Sometimes, automation is a time-saver. Auto-routing is merely a time-saving tool. Perhaps some of us remember the American Automobile club trip-tiks, their suggestion of a route, on paper maps, to get to a distant location. I don't think any of us would blindly follow those routes without verification but they sure were a good starting point.

Twisted you put it very well. BD you make good points. Since starting this thread and following it down it's divergent paths I've got a better understanding of why some like auto routing.

I am not one, nor will I likely be. Mvweebles gave a good opinion up thread I agree with. Planning routes is part of the joy in voyage planning. I don't want to let automation take that from me

Another thing to consider is that good route planning is more than the hard data of tides, currents, depths and the positions of nav aids. It's also experience, judgement and local knowledge which automation cannot replace.

For those with considerable experience why let automation make your decisions? For those without much experience how will you gain said experience if you let automation do the work?

That said if your planning tool is a plotter on an MFD then I can understand why you would let automation do the work. They are at best cumbersome to enter and edit waypoints. I much prefer to do my planning on a laptop with a 15" screen running straight forward easy to use software.

 

[mvweebles]

In catching up with this the last 25 posts in the thread, I see that proponents of autorouting are in narrow, twisting areas such as the ICW. A couple years ago I went from San Francisco go Ensenada, a distance of 500 nms non stop. The route had 14 waypoints. Going two miles on the ICW could include a couple dozen waypoints. A days' run of 50 nms in the ICW could easily include 100+ waypoints. Leaving aside the tedium of manually creating a route of that many waypoints, the chance of human error is pretty high. There's a decent positive safety case to be made for autorouting in instances such as this.

Peter

 

[BDofMSP]

Of course the auto route knows about the tower too, and avoids it. It's not limited to what you see at any particular zoom level. If anything this supports the use of the tool.

With. Proper. Review.

BD

 

[Portage_Bay]

Excellent point about not letting automation make the decisions. That is in my opinion the ONLY way to use auto routing. However, if we go back to my OP recall that I started this thread because another TF member said in another thread "This morning we were at Poulsbo and was thinking of heading out via agate pass but garmin didnt allow me to take that route. I went south instead but wanted know if there was a reason one should avoid that pass? ". He let Garmin make the decision and ended up going out of his way following a route that is more challenging than Agate Pass.

He later figured out that after an update his desired depth was set to 30 fathoms. This is a case for the old acronym GIGO. Garbage In Garbage Out.

I see that you are in MD? That implies you're cruising the ICW? It would explain your need for 100,200 waypoints for a day's cruising. In that case I might look more favorably on auto routing. Especially if using a MFD or hardware plotter.

Portage, with respect, using automation is not letting it make the decisions. It is merely a starting point, a suggestion to be verified and modified based on experience and local knowledge, that is, if one has local knowledge. I do not have time nor would I enjoy in the least plotting 100, 200 waypoints or more manually every evening on a long cruise. I'd rather relax, have a brew and enjoy a good meal. Sometimes, automation is a time-saver. Auto-routing is merely a time-saving tool. Perhaps some of us remember the American Automobile club trip-tiks, their suggestion of a route, on paper maps, to get to a distant location. I don't think any of us would blindly follow those routes without verification but they sure were a good starting point.

 

[psneeld]

I used a computer based plotter (OpenCPN) on the ICW to give me ETAs to bridges, destinations, or other important items. Even on the most twisted sections and 50 mile legs, I doubt I ever used more than 50 or so waypoints and always had ETAs within minutes of actual arrival times.


I use the AP much of the time in the ICW, but on heading only or maybe track/Auto on those mile or more straight sections where my route line coincides with the channel.


There are lots of places in the ICW that autorouting probably does come in handy...but for me, those areas really don't need many waypoints so taking about 5 minutes in OpenCPN isn't a big deal to me.



But to waste the time trying to get all the necessary waypoints plotted to take care of all the winding....never gonna happen. Long curves or severe winding would be overly tedious....and in my judgement really not needed.

 

[wkearney99]

My two cents is auto routing is handy for estimates and as a starting point for a manually adjusted route. As in, the weather conditions are sketchy... just how long would it take to get to x, y or z points along the way? Hmmm, ok then, let's see about planning that.

In the limited areas we generally go boating there's not a lot of variation. Not much in the way of dramatic shoaling changes or big tidal influences. But from what I read about other places, auto-routing would be a big concern. I wouldn't trust automatic routing through areas that have known frequent shoaling changes or huge rushes of tides impacting making way. I'm not likely to be traveling into those areas any time soon, so it still wouldn't make much difference to me. Trouble is from the little I've seen of automatic routing setups in recreational chartplotters or apps, they don't seem to have a lot of that 'local knowledge' integrated with their routing.

So I'd fall back to my original statement, they're handy for estimating. And with local knowledge, as starting point for a manually planned route.

 

[jhall767]

Most of the anti-autorouting group sound like my friend who doesn't like adaptive cruise control and lane departure warnings.

The arguments against both are mainly that people will use it in the wrong way.

Or it doesn't know about something that's not on the charts...
Or it's not up to date. My navionics app updates just about every time I load it.

If you don't feel comfortable using it that's fine. But it's just another tool in the tool box.

Someone made a statement earlier that the following is "silly";
It's very useful for calculating ETA at bridges or marina's or anchorages.

Are we going to make the next opening?
Will we get there before the fuel dock closes?
Will we make that anchorage with enough daylight or should we find a closer one?

Having the route in the plotter helps you decide if you need to push up the throttles or back off. The plotter will continuously recalculate the ETA.

Is is perfect? Hell no but it gives you a baseline projection. Running the ICW your speed changes all the time. No wake zones, passing fishing boats, kayakers, work boats, overtaking slower boats, etc. Pass an inlet - you might lose or gain 3 knots.

Now for the real leap of faith - Offshore I use an online routing web page to use/avoid the currents and weather

 

[psneeld]

Yes.... autorouting is quicker if it plans a long ICW run in less than 5-10 minutes AND it places waypoints at the bridges (or you do) to get those ETAs for openings.



As far as changing speeds, any chartplotter can only calculate ETAs based on either an actual speed or an average speed which only gets more accurate the closer you get to a waypoint or destination.



But doing the same thing manually usually only takes me minutes and gives me the info to waypoints too. So yes it is a timesaver but it's not the only tool that does the same thing. Unless of course there is a page where it gives you the ETA to ANY waypoint in the entire set....then I agree that is a great tool to have.


Guess I get confused between people discussing autorouting and just following a route on any old chartplotter.

 

[Simi 60]

We use the Admiral Adama method aboard our vessel
No integrated computers, everything is stand alone.

Auto route is something I can use on my tablet with our backup navionics
It is something I can use on the wheelhouse PC with Navionics web app when we have a mobile signal

I can manually plot a course with OpenCPN or our dedicated marine plotter but neither of them are linked to the autopilet

Autopilot is used extensively, but only to hold course from point A to B and then manually changed to point C and D etc
Course adjustment due to current are made manually as required.

We have control of our vessel, not some damn computer

 

[caltexflanc]

I used a computer based plotter (OpenCPN) on the ICW to give me ETAs to bridges, destinations, or other important items. Even on the most twisted sections and 50 mile legs, I doubt I ever used more than 50 or so waypoints and always had ETAs within minutes of actual arrival times.


I use the AP much of the time in the ICW, but on heading only or maybe track/Auto on those mile or more straight sections where my route line coincides with the channel.


There are lots of places in the ICW that autorouting probably does come in handy...but for me, those areas really don't need many waypoints so taking about 5 minutes in OpenCPN isn't a big deal to me.



But to waste the time trying to get all the necessary waypoints plotted to take care of all the winding....never gonna happen. Long curves or severe winding would be overly tedious....and in my judgement really not needed.

I agree with this 100% and it closely mirrors the way we navigated the ICW as well.

 

[Simi 60]

...
Or it's not up to date. My navionics app updates just about every time I load it.

Doesn't mean it's correct

 

[mvweebles]

Doesn't mean [chart data] is correct

This brings up a good point. Users rely heavily on the accuracy of their chart plotter. But buried deep in the ENC data are accuracy factors (I forget the actual name of the variable - they are semi-visible in OpenCPN). Main shipping channels are very accurate. Small off-shoot channels....not so much. Unfortunately, on an ENC/Chart Display, everything looks similarly accurate.

https://iho.int/uploads/user/pubs/s...ccuracy of Depth Information in an ENC_EN.pdf

In short - read the water, look out the window, watch the depth sounder.

Peter

 

[Roger Long]

If you have reviewed the route in detail (zoomed in) what is the difference compared to a route that you plotted yourself?

My impression of dedicated auto route users is that they use them to avoid doing all that stuff. Take a look at some of the Facebook pages dedicated to ICW navigation. You won't believe the questions. A fellow named Bob creates tracks of deepest water that are like the new magenta line. It's great info but it's creating a whole new breed of navigators. Someone followed his tracks up from FL to Norfolk and the asked how they could continue on to New England since he doesn't provide tracks except on the ICW!

 

[wkearney99]

And of course the conversation predictably degrades into complaints about technology making it 'too easy' for people to participate.

Newflash, people are going to do dumb things and pretending that gatekeeping arcane knowledge will somehow prevent them from trying is naïve, at best.

 

[BDofMSP]

The fact the technology enables stupidity doesn't mean that using it is stupid. There are so many responses that say "well it doesn't have local knowledge". Well then apply the local knowledge to the generated route. Then they say "well people don't do that". Well I don't care what "people" do - I care about what I do. Why should someone not use the convenience appropriately just because others don't?

BD

 

[Simi 60]

The fact the technology enables stupidity doesn't mean that using it is stupid. There are so many responses that say "well it doesn't have local knowledge". Well then apply the local knowledge to the generated route. Then they say "well people don't do that". Well I don't care what "people" do - I care about what I do.

BD

Then I may as well plot the course myself and get it right the first time vs let the machine do it wrong then me correct the mistakes.

Why should someone not use the convenience appropriately just because others don't?

Convenience is when it gets it right 100% of the time

 

[BDofMSP]

I've explained why this is still convenient in previous posts, but I'm not hashing over it again. I'm not trying to convince anyone to use it. I do resent the implication that people who do use it are irresponsible.

BD

 

[Bacchus]

The fact the technology enables stupidity doesn't mean that using it is stupid. There are so many responses that say "well it doesn't have local knowledge". Well then apply the local knowledge to the generated route. Then they say "well people don't do that". Well I don't care what "people" do - I care about what I do. Why should someone not use the convenience appropriately just because others don't?

BD

Exactly!

Then I may as well plot the course myself and get it right the first time vs let the machine do it wrong then me correct the mistakes.



Convenience is when it gets it right 100% of the time

If thats what you prefer that is certainly your choice.
I dont get it right 100% of the time and always make it a habit to double check myself or any other route provided by others or any software. Maybe you are better than I and never make an error in waypoi to or routes.
Auto route has been a VERY useful tool for me in SOME situations.
I NEVER follow blindly and it is a backup for either a route I plotted or visual Nav with the auto route as a guide.
Too bad so many are so closed minded and willing to toss a potentially useful tool in SOME SITUATIONS.
As with many things trust but VERIFY!