direction of travel as indicated by icon and predictors

[GreenHeaven]

https://paste.pics/a52a7b11210204e90d6d3e97fa27157d

this was some fairly heavy weather but what can I do to improve this?
GPS data is available to opencpn obviously

[bdbcat]

Green...
The long line is your ship's heading. Does not usually come from GPS. Must be some other heading sensor in you NMEA0183 stream. Is it calibrated? Are you using the WMM plugin to automatically apply Variation? And finally, what OpenCPN version?


Thanks
Dave

[GreenHeaven]

Originally Posted by bdbcat

Green...
The long line is your ship's heading. Does not usually come from GPS. Must be some other heading sensor in you NMEA0183 stream. Is it calibrated? Are you using the WMM plugin to automatically apply Variation? And finally, what OpenCPN version?

Thanks
Dave

Thx for the response Dave. I know you are busy
I have a mulitplexer that is combining Raymarine seatalk, NMEAE2k and Nmea 0183 data to a 0183 wifi feed.

I assume the ships heading is from the Raymarine Evolution Auto Pilot

With the new Autopilot EVOLUTION from Raymarine, steering your boat becomes easier than before. Difficult calibration is no longer necessary. Due to the intelligent EV-sensor, the autopilot monitors multiple ship movements in all directions and automatically adjusts the steering to match existing sea conditions, without the user having to adjust any other settings. Safe arrival at the planned destination is guaranteed. A further big advantage of the autopilot is flexibility of installation. The device itself can be installed where it is easiest for you to access, while the EV-sensor can be mounted where it makes most sense to you, no matter if above or below deck. There are no restrictions concerning the installation compared to common heading sensors.The core of the sensor is water-protected to IPx6 and IPx7. You can connect the different components very easily via SeaTalk. The required cables and rudder reference unit are included. Furthermore, the autopilot is NMEA2000 compatible.

However, none of these correlate to the ACTUAL heading of the boat as the OCPN trak attests

Could this be a rounding error in the 2k to 0183 multiplexing?
The heading set and displayed in the RM head unit is different from the heading s calculated in OCPN (presumably from GPS data) even in flat calm no wind motoring.

I notice the depth numbers on the RM head unit do not always correlate with that shown in OCPN

Sionce RM say their calibrating is automatic, is the a way to align these with a configurable offset perhaps?

[Hakan]

Originally Posted by GreenHeaven

The heading set and displayed in the RM head unit is different from the heading s calculated in OCPN (presumably from GPS data) even in flat calm no wind motoring.

OCPN can make true heading calculation, HDT, from a magnetic heading, HDM/HDG(M). Never from any GPS data!

If your NMEA data stream contains a magnetic heading and you didn't activated plugin WMM the result could be as of your picture dependent on the local variation.
Did you enabled plugin WMM?

[GreenHeaven]

Originally Posted by Hakan

OCPN can make true heading calculation, HDT, from a magnetic heading, HDM/HDG(M). Never from any GPS data!

If your NMEA data stream contains a magnetic heading and you didn't activated plugin WMM the result could be as of your picture dependent on the local variation.
Did you enabled plugin WMM?

er no.

whats a maghnetic heading?
There is nothing generating a heading from a compas that I know of

[bdbcat]

GreenHeaven...
Sure would be useful to see a screenshot of the NMEA Debug window, while running normally.


Thanks
Dave