AUTO ok, TRACK seems to hunt

[Keith Pleas]

I've got an EVO (ACU-400, hydraulic, 37 ton, 44' trawler) and it does reasonably well on AUTO.

I then hooked up Coastal Explorer to my RM/N2K network (with Actisense USB connector), start a route, and then select TRACK from my P70R.

The EVO follows the track but seems to do a LOT more steering correction. I sort of get this...it's not just trying to steer a heading but it's also trying to continually get me back on the course track...but I have feel it's over-correcting for the track. Unfortunately I only have the Performance/Leisure/Cruise settings and they don't seem to have a significant effect.

Is there a setting to dial down the EVO from making small corrections to get me back on the track? Or should I be looking to CE (I know the developer) for an option on their end?

[Keith Pleas]

I also asked this on the Coastal Explorer forum and the response there was:
"It's all controlled by the auto pilot, not CE. When you activate a route on CE, CE just starts broadcasting the next waypoint info and the current cross track error. It's all up to the AP to decide what to do with that info. CE doesn't even know if the route is being followed or ignored.

Most APs have some way to adjust how aggressively it tries to stay on track."

Someone else replied that ComNav allows "can be set to steer by crosstrack to minimize the crosstrack error, set to steer to waypoint and ignore crosstrack error, or a combination of the two"

So...how do I tell the EVO not to aggressively make the XTE zero? I looked through the docs but didn't find anything. I did find this sentence in the P70 manual for LARGE XTE: "Reset XTE on the multifunction display" but there's no description anywhere of how to perform that.

With the new "autorouting" I would think this would become a huge issue. And it's not new - Ben Ellison had a long post about it back in 2011.

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum Keith,

The Reset XTE feature would not be used for this purpose. Essentially, the Reset XTE feature will cause a new course line to be drawn from the vessel's current position to the destination waypoint, effectively zeroing the XTE. The Pilot Response feature would typically be the feature used to control the amount of autopilot corrections performed and how closely the autopilot will track to the course line.

It is recommended that the autopilot's software levels be checked to ensure that the Evolution autopilot components have been updated with the latest software updates. It is further recommended that any speed through water transducers be checked for problem operation and calibration. Please click here to view a FAQ addressing this subject. Should a rudder transducer not have been fitted to the system, then you may want to consider installation of a rudder transducer to further improve the autopilot's performance.

[Keith Pleas]

Hi Chuck -

I've been keeping up with the updates, but I saw on Panbo that there's a new one out this week so I can do that.

I don't have a STW input, but I do have a Raymarine rotary rudder sensor. Now it's true that I have a non-standard setup for that input (we covered this in the old forum) - it's being input to both a Raymarine (I think it's ST60+) and the ACU. I was going to do Seatalk to STNG and have the connection kit but haven't installed it yet.

And I have several heading sensors. That might be the issue - when on AUTO I'm using the EV1 plus I forget when GPS, but when on TRACK the XTE is coming from Coastal Explorer and...I also forget where it's getting GPS input. Perhaps that input is moving back and forth say 50 feet and that is causing the ACU to "hunt" for the course.

One option I could try is the GPX eport, import into the ACU, and try to TRACK from my a78 MFD. That's a brutal sneakernet process but the only one I know to transfer WPs.

UPDATE: Just got off the phone with Lee. There's a new "Enhanced Track Keeping" algorithm in last Thursday's software update may address this issue. He said it will gradually bring me back to the course line depending on distance to the WP. But I will go through the process (and, BTW, I must do a factory reset on the ACU, P70R, and A-series MFD after the update) and report back if anything changes.

[Chuck - Raymarine - Moderator]

Keith,

Per our phone conversation, it is recommended that all Raymarine products within your system (ex. a78 MFD, EV-1 Sensor Core, ACU, p70R, etc.) having software updates posted on Raymarine's web site be updated with the latest available Raymarine product software updates. As has been indicated on the a/c/e/eS/gS-Series MFD software update page, following installation of the latest Evolution autopilot component software updates, the autopilot must be re- calibrated. As Lee had suggested, using the autopilot's Factory Reset option to be followed by execution of the Dockside Wizard, brief cruise to establish the deviation table (seeking a maximum deviation of 10 degrees), followed by application of the compass offset (should the heading reported by the autopilot differ from any properly calibrated vessel compass be determined).

As indicated within our discussion, navigational systems must be restricted to single sources of any specific data item (ex. GPS (lat, lon, COG, SOG, etc.), Heading, Wind, rudder, etc.) or performance of the system may be adversely impacted. Raymarine's a/c/e/eS-Series MFDs have a Data Sources feature (HOME->SET-UP->SYSTEM SETTINGS->DATA SOURCES) which may be used coordinate which source of each type of data will be used by Raymarine devices. Should one also be employing a third party navigational system product (ex. chart plotter, MFD, computer based navigational application, etc.) then these items will all need to be configured to use the same data sources as have been specified within the Raymarine system. With respect to heading, it is strongly recommended that the EV-1 Sensor core should be specified as the heading data source for the system. Having multiple data sources within the system and/or old software may well account for the reported tracking issue.

As Lee indicated, the latest autopilot software includes some important/useful performance enhancements and features.

With respect to waypoint/route transfer to a Wi-Fi equipped a/c/e/eS/gS-Series MFD, wireless transfer of such data is exclusively supported by Voyage Planner PC software, the Navionics Boating app, and possibly Fugawi Marine 5 software (recommend verifying with Fugawi). Raymarine has logged and is considering a feature request to additionally include support for waypoint/route transfer via NMEA 0183 and/or NMEA 2000 communications protocol. Raymarine has not yet announced support this feature addition. As you have indicated waypoint/route data may be transferred between third party chartplotting products via GPX files stored on microSD memory cards ... this is the most commonly used method transfer.

[Keith Pleas]

Thank you Chuck for the phone call and for the detailed summary. I will do the upgrade and report back on any improvement. And I will ensure that both the AP and CE are using the same GPS source.

[EScott5406]

I am having the same issue. On GOTO the autopilot continually works back and forth a couple degrees over the rhumb line. I am up-to-date as of June 1st using the c97 online update feature. I went through Dockside Wizard and the compass routine (thanks for the compass progress bar); got 9 degrees deviation. I did circles and figure eights a number of times over a four hour/20 mile period. Aligned compass/GPS. Have left compass and calibration locks "OFF."

System: c97 & c95, EV-1, ACU400 with type 2 linear, p70

[Chuck - Raymarine - Moderator]

EScott5406,

Is the system equipped with a speed through water transducer? Was the rudder reference transducer installed along with the other autopilot components? What is the autopilot's Response Level configured to?