Gyro/Smart Heading for Raymarine Autopilot

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Gypsy

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A couple of weeks ago there was a discussion (started by BoatMike I think) about gyros for autopilots. I believe he was looking for one with higher accuracy than the Raymarine option. It the ensuing discussion it was noted that there was a difference of opinion as to how the Raymarine Gyro should be installed and where the fluxgate compass should connect.

I have just completed installing a Raymarine Smart Heading Sensor to my boat and what I have discovered may answer some of the questions.

Firstly the Smart Heading Sensor (SHS) is essentially the same as that which was known as the GyroPlus2 but it comes in 2 versions, gyro only for adding to a system which already has a fluxgate compass and a combined gyro and compass version for use with other instruments such as radar MARPA. The gyro is electronic using a special capacitive accelerometer chip, so no moving parts.

My Autopilot is a 6001+ using a 400 course computer (vintage 2002). It has a Raymarine fluxgate compass connected to the computer so I purchased the Smart Heading without the compass. I also have a RL70+ radar and RC530+ chart system of the same vintage.

The instruction book of the SHS has an appendix for installing to systems with both Autopilot and Radar/Chart. The SHS has inputs for a fluxgate compass, SeaTalk and power and outputs a Turn Rate signal to the computer. The book tells you to leave the fluxgate connected to the autopilot but connect Seatalk (and separate power in some situations) to the SHS and connect the Turn Rate to the course computer. For enhanced MARPA operation the book tells you to take the NMEA1 output from the computer to the radar/chart systems. This is a special fast update HDG signal, not the complete suite of NMEA sentences.

Having completed this I was faced with 2 problems.
1) The RED LED which is used to indicate turning to Port was flashing. Reading the book again I see the flashing mode is to indicate that no compass is connected. For the peace of mind I connected the compass temporarily to the SHS and it stopped complaining (flashing) but I returned the compass to the computer. The flashing Red can be ignored for this type of installation.
2)The HDG data on my Chart system was wrong and flicking to another reading by 90deg and more, as was the HDG signal on the data display of my Nav6+ unit which I use at the nav table as a repeater for many NMEA signals (via a Seatalk/NMEA converter). The Radar HDG data was stable.
After some thought and diagnotic work I realised that the SHS system was putting out an erroneous Seatalk HDG signal (248deg) whilst the course computer was putting out the correct HDG on Seatalk and NMEA1. The devices seeing the Seatalk signal had the flicking HDG data whilst the Radar which ignores Seatalk HDG when NMEA is present was quite stable and happy. I had not connected NMEA to the Chart system at this time as I was not sure why it was necessary since the MARPA work is done in the Radar.

It is possible this is where the argument arises about where the fluxgate should be connected as when connected to the SHS and not the computer this would not occur as the SHS would be the only source of the Seatalk HDG data.

Solution. Disconnect Seatalk from the SHS, it does not need it when the fluxgate is not connected to it, and ensure NMEA1 is connected to BOTH Chart and Radar. The SHS puts out 248deg when no compass is connected. These "fixes" were confirmed by the Raymarine engineer in their Australasian support group here who suggests it was an oversight that the manual does not include this instruction for this type of installation.

By the way, I had to have the software updated on my Radar and Chart systems for them to work correctly with the SHS. Raymarine did this for just the cost of the engineers time, half an hour per device.

I have not had the chance to test the effectiveness of the system in difficult conditions yet but all looks good so far.
 
[ QUOTE ]
Solution. Disconnect Seatalk from the SHS, it does not need it when the fluxgate is not connected to it, and ensure NMEA1 is connected to BOTH Chart and Radar.

[/ QUOTE ]I seem to remember that when I fitted my Smart Heading System, the calibration procedure relied on having SeaTalk connected. If you disconnect SeaTalk, how are you going to calibrate the Smart Heading System?
 
Phew! That is an example of why I have gone right off Raymarine!
I actually solved my problem by getting an £80 software update for my Robertson Autopilot which now gives 10Hz rate stabilised output. 2 wires up to the Radar and job done! /forums/images/graemlins/smile.gif
 
Mike, that's a good solution and well worth you continuing to look for one which did not require extra hardware. How do they provide the stabilised output without a gyro? It must be a software algorithm from their compass and perhaps learning from the rudder movement unless they have some other type of sensor.

I'm more ready to defend Raymarine because they have led the field of fully integrated Raymarine solutions which work well but I accept the point that it is not always easy to mix with other suppliers. From my view, I was pleased to find that I could still buy a "Gyro" option 6yrs after my original purchase...that's not bad these days.
However there are more companies now which can offer fully integrated systems so the dynamics are changing.
 
Hi Ray. I have a same problems with my equipment. I have contact Raymarine and their answer for red flashing light was that it is OK. My problem was Seatalk red wire in Course computer. As I have computer connection by separate +/- 12V another power connection made faults on the way that during normal autopilot operation, at the moment, course was changed for 90 deg. After that I have disconnect red wire from the computer and everything was fine.By the way, my seatalk from SHS is connected to RL80CRC ( who know maybe I had identical problem with false heading from SHS - and will have it!)
Regarding Marpa - it works on 5 Hz but on the rough sea is unusable without NMEA 10Hz .
 
The Seatalk cable needs to be connected ONLY to supply power to the SHS - so you must disconnect the data cable into the SHS. You also need to connect power from the Chartplotter feeds as well in case you have Radar working and not the instruments and vice versa - see Raymarine manual.

The SHS does make a huge difference to the performance of the autopilot and the MARPA so well worth the hassle and the expense.
 
[ QUOTE ]
You also need to connect power from the Chartplotter feeds as well in case you have Radar working and not the instruments and vice versa - see Raymarine manual.

[/ QUOTE ]Just to clarify this - presumably the radar/plotter can only receive fast heading data if the autopilot's course computer is powered up, so is adding a feed from the plotter still required?
 
[ QUOTE ]
Just to clarify this - presumably the radar/plotter can only receive fast heading data if the autopilot's course computer is powered up, so is adding a feed from the plotter still required?

[/ QUOTE ]

Good point - I just did what the manual said. The point is that if you turn off the Radar with a breaker to save power then the Gyro needs power via Seatalk - otherwise it reverts to normal Autopilot operation. You can tell when its working with full Gyro by switching to the response level setting. There are 9 levels with the rate gyro connected - only three without it.

If you did turn off the instruments - if say a fuse blew - then you would want the course computer and radar powered from the same source.
 
There is a lot of misunderstanding regarding the terminology here Gypsy. The Raymarine is NOT a gyro-compass. The cheapest proper gyro-compass I know of costs about £3000 rising to £15,000 for a good one. What you have is a "rate stabilised" fluxgate compass, which is good enough but not as good as a full gyro.
In a gyro-compass the compass is stabilised by a spinning gyroscope which will keep the compass on an even keel regardless of the pitch and yaw of your boat and ensure that indicated changes in the compass heading are true indications of the course changes on your boat in real time. A fluxgate on it's own will pitch and yaw and send raw data to the reading instrument that fluctuates wildly. So what the Raymarine box of tricks does is "rate stabilisation" which is take this raw data and electronically "stabilise" or damp it to remove the wild fluctuations and give a reading that gets nearer to that which you would expect from a proper gyro.
This software is the same that is found in more expensive autopilots from Raymarine, but not their cheapie autohelms. It is what I already have in my Robertson. So the compass output from any good autopilot should be rate stabilised. That's not the end of the story though because you need the speed of input of that information from the RS box to be at least 10Hz for MARPA to give any useful results. That's what I needed the software upgrade for. My pilot is 1996 vintage so only output 5Hz. The upgrade was sent from Denmark on an E-Prom and installed for me by Greenham Marine, total cost £80. Try getting that kind of support from Raymarine for a 12 year old piece of kit!
 
[ QUOTE ]
The upgrade was sent from Denmark on an E-Prom and installed for me by Greenham Marine, total cost £80. Try getting that kind of support from Raymarine for a 12 year old piece of kit!

[/ QUOTE ]

You are obviously not "in" with Greenham & Simrad, my software update didn't cost me a penny. By the way, the rate sensor input with the fluxgate compass not only "stabilises" the fluxgate output but also reduces heading change lag and overshoot on fast changes thus increasing heading output accuracy when there is a high rate of turn. It is to gain this advantage that you need NMEA HDG updates at a frequency of at least 10Hz.
 
You are obviously not "in" with Greenham & Simrad, my software update didn't cost me a penny. By the way, the rate sensor input with the fluxgate compass not only "stabilises" the fluxgate output but also reduces heading change lag and overshoot on fast changes thus increasing heading output accuracy when there is a high rate of turn. It is to gain this advantage that you need NMEA HDG updates at a frequency of at least 10Hz.
----------------------------------------------------------------------------------------------
Yeah I know. You told me before, but didn't you buy a new compass unit? I didn't and it's Navico now not Simrad.
Having already bored myself shitless writing all that crap I thought I had enough pedantic detail already. But yes of course you are right
 
Yes Mike I know what a true Gyro is and that is why I deliberately avoided calling it one, it is other marketing types which used the Gyro tag, I went with the new product name, SHS. However the SHS is more than a processor of the fluxgate compass signal. It has a solid state device which is a capacitive accelerometer and it is this which gives additional information about the yaw of the boat. The SHS has circuitry and software/firmware to take the fluxgate signal and process it with the yaw information to produce the fast HDG NMEA signal itself when there is no Raymarine AutoPilot, but in my combo installation I am only using the SHS to provide the Yaw info to the CComp which does all the maths to produce the fast HDG message.

In fact the SHS is overkill for my needs since it duplicates some of the processing features of the CComp, what I really needed was the original "Gyroplus Yaw Sensor" produced by Raymarine but no longer available (even tho I monitored ebay in hope of finding one). I haven't seen inside one but I assume it was a similar solid state accelerometer but without any processing against/with a fluxgate compass. It connected to the 300 or 400 computer providing the yaw (turn rate) signal.

It was never my intention to promote the SHS as a true gyro or even a “best results” solution. I purchased it on the basis of good anecdotal evidence that it improved downwind autopilot performance and more reliable MARPA operation in difficult sea states. Maybe it will, maybe it won’t but the main aim of the post was to give some clues to the discussion of how it should be integrated and the issues of that process.

I am interested that you seem satisfied that a software upgrade to your Robertson A/P will suit your needs after your initial posting was to find a gyro. The software upgrade does not seem to get any additional information from a gyro or yaw sensor so whilst a better algorithm with existing compass/heading/rudder data can be expected to give improvement, without yaw info it will have its limitations. Is this just an interim solution for you?

For others, the power situation is as follows: There is a separate power input and the SHS can take power from Seatalk. The manual makes various suggestions for connections depending upon how the rest of the system is powered. If the SHS is used for MARPA and Autopilot you have to be sure that there is power available via direct input or Seatalk even if the Radar/Chart is off, or contrarily if the Autopilot is off.

In my case I power it from Seatalk because that is my main instrument power circuit. It will be ON at all times except for a catastrophe.
 
I have a new Raymarine E-120 radar unit. I purchased a new fluxgate compass as recommended by Raymarine to all the radar overlay work properly on the gps map. I paid a dealer to install the equipment. The radar seems to work fine. However, the image on the plotter shows the boat exactly 180 degrees opposite to the direction I am traveling. Raymarine can't help me fix the problem and the dealer has no clue as to what the problem is. I suggested that maby the compass should be mounted facing the front of the boat. Raymarine indicates that as long as the arrow on the compass points up it doesn't matter whether the compass points to the fore or aft of the boat. Can anyone help me solve this problem?

Herb
 
When I first installed my S1 Raymarine autopilot I installed the included fluxgate compass in the most convenient position, facing aft on the pilothouse bulkhead. The resulting compass heading was 180 degrees out. Thinking that there would be a simple set-up procedure to add 180 (modulo 360, of course) to the digital input to the computer I went through all the many possible adjustment parameters - no, I had to re-site the unit on a forward facing surface. It now works properly but I am still surprised that this simple conversion was not possible.
 
No need to move anything. There is a simple method detailed in the S1 handbook to set the fluxgate heading reading to be the same as your COG. It is all done automaticaly via software.
 
Hmm, that implies a GPS connection, which I've not bothered with as the plotter is Garmin and I'd have to use NMEA 0183. Anyway, we have to leave something for some human interaction - AP steering to a waypoint seems a step too far for this old fart.
 
First, on-topic comment:

I recently started working for the Beneteau import in my country. And unfortunatly, Beneteau are standard pre-installed with Raymarine. Since then, I've seen poor quality in fancy boxes! E and C series display with phantom waypoints (working with muxer) to manipulation disorders (fixed with updates tough)
This SHS problem I encountered as well. If Raymarine systems are this well-integrated, can anyone tell me why one can't just plug in the seatalk cable into the VHF for DSC purpose? No, it has to be NMEA! Anyway, if you wan't a decent pilot with integrated "gyro" (read accelerometer) and standard fast heading compass go see for nke. At least, this brand does offer a bus-connection worthy to be called a bus.
Try your pilot holding your boat on the edge of gybe with spinacker nicely blown up.. Raymarine can't do that! I own a Figaro II nke equipped and proud to say my pilot does it perfectly.. even better than I could.. sad to say.
If Raymarine just spent less time adding buttons and little lights to their instruments to make them look pretty and more time making sure what they put on the market is fully reliable I most certainly would revise my oppinion.
 
Gypsy said:
A couple of weeks ago there was a discussion (started by BoatMike I think) about gyros for autopilots. I believe he was looking for one with higher accuracy than the Raymarine option. It the ensuing discussion it was noted that there was a difference of opinion as to how the Raymarine Gyro should be installed and where the fluxgate compass should connect.

I have just completed installing a Raymarine Smart Heading Sensor to my boat and what I have discovered may answer some of the questions.

Firstly the Smart Heading Sensor (SHS) is essentially the same as that which was known as the GyroPlus2 but it comes in 2 versions, gyro only for adding to a system which already has a fluxgate compass and a combined gyro and compass version for use with other instruments such as radar MARPA. The gyro is electronic using a special capacitive accelerometer chip, so no moving parts.

My Autopilot is a 6001+ using a 400 course computer (vintage 2002). It has a Raymarine fluxgate compass connected to the computer so I purchased the Smart Heading without the compass. I also have a RL70+ radar and RC530+ chart system of the same vintage.

The instruction book of the SHS has an appendix for installing to systems with both Autopilot and Radar/Chart. The SHS has inputs for a fluxgate compass, SeaTalk and power and outputs a Turn Rate signal to the computer. The book tells you to leave the fluxgate connected to the autopilot but connect Seatalk (and separate power in some situations) to the SHS and connect the Turn Rate to the course computer. For enhanced MARPA operation the book tells you to take the NMEA1 output from the computer to the radar/chart systems. This is a special fast update HDG signal, not the complete suite of NMEA sentences.

Having completed this I was faced with 2 problems.
1) The RED LED which is used to indicate turning to Port was flashing. Reading the book again I see the flashing mode is to indicate that no compass is connected. For the peace of mind I connected the compass temporarily to the SHS and it stopped complaining (flashing) but I returned the compass to the computer. The flashing Red can be ignored for this type of installation.
2)The HDG data on my Chart system was wrong and flicking to another reading by 90deg and more, as was the HDG signal on the data display of my Nav6+ unit which I use at the nav table as a repeater for many NMEA signals (via a Seatalk/NMEA converter). The Radar HDG data was stable.
After some thought and diagnotic work I realised that the SHS system was putting out an erroneous Seatalk HDG signal (248deg) whilst the course computer was putting out the correct HDG on Seatalk and NMEA1. The devices seeing the Seatalk signal had the flicking HDG data whilst the Radar which ignores Seatalk HDG when NMEA is present was quite stable and happy. I had not connected NMEA to the Chart system at this time as I was not sure why it was necessary since the MARPA work is done in the Radar.

It is possible this is where the argument arises about where the fluxgate should be connected as when connected to the SHS and not the computer this would not occur as the SHS would be the only source of the Seatalk HDG data.

Solution. Disconnect Seatalk from the SHS, it does not need it when the fluxgate is not connected to it, and ensure NMEA1 is connected to BOTH Chart and Radar. The SHS puts out 248deg when no compass is connected. These "fixes" were confirmed by the Raymarine engineer in their Australasian support group here who suggests it was an oversight that the manual does not include this instruction for this type of installation.

By the way, I had to have the software updated on my Radar and Chart systems for them to work correctly with the SHS. Raymarine did this for just the cost of the engineers time, half an hour per device.

I have not had the chance to test the effectiveness of the system in difficult conditions yet but all looks good so far.
Click to expand...

Hi,

I know this is a old posting but... I have a Raymarine C80 Plotter/Radar and a old vintage Autohelm T300 course computer with the fluxgate connected to it. In addition I have on the t300 course compute a rate sensor (option). I know that the course computer only take into consideration the rate sensor input while set on Response level #3 which is according to the manual required when use on a fast moving power boat (I am on a 35ft cutter sailboat). On that response level, the course computer is very busy keeping a very tight course and does not settle much. On Response Level 1 & 2, the course computer lack of yaw input and does large coarse corrections at longer interval often synchronized to the swell period. I have tried adjusting other parameters (rudder gain, rate...etc) but have not been able to find the right balance without the yaw rate input.

Anyways, I was wondering if you can tell me if my course computer would take into account a yaw information produce by a HDG sensor connected via NMEA input ? and secondly if it does, would it also work for the other Response Level settings (#1 & 2) ?
 
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