I would like to control my Raymarine ST1000 Plus Autopilot, somehow
from a GPS without use of the internal compass. This would eliminate
the problems of the boat motions affecting the compass.
Is this possible?
Or can the boat motion / compass problem, in heavy sea, on a small
boat, be solved in an other way?
By wind vane control?

Thanks Urs

On 23 Feb 2007 08:13:31 -0800, "muelec" wrote:

I would like to control my Raymarine ST1000 Plus Autopilot, somehow
from a GPS without use of the internal compass. This would eliminate
the problems of the boat motions affecting the compass.
Is this possible?
Or can the boat motion / compass problem, in heavy sea, on a small
boat, be solved in an other way?
By wind vane control?

Thanks Urs

From my observations, an autopilot guided by GPS still uses its (or a)
compass as a heading reference.

When first engaging "steer by GPS", the autopilot will turn the boat
to the "bearing to waypoint" indicated by the GPS - and it can only do
that by comparing the compass heading to the GPS-provided bearing.
Once on-course, the autopilot turns its attention to the cross-track
error information provided by the GPS, and adjusts its "desired
heading" to minimize XTE - but it is still using its compass as a
heading reference.

You could add a SeaTalk compass to the system - the autopilot would
use that compass instead of its internal compass. I don't know if the
external compass would improve the pilot's performance to any
extent...


--
Peter Bennett, VE7CEI Vancouver BC, Canada
peterbb4 (at) interchange.ubc.ca
new newsgroup users info : http://vancouver-webpages.com/nnq
GPS and NMEA info: http://vancouver-webpages.com/peter
Vancouver Power Squadron: http://vancouver.powersquadron.ca

Well,

In my practical experience, when using the gps track mode (gps
interface ) with my autopilot St/4000 for several years, is that the
boat has much better tracking, with less yawing, staying much better
over the route and spending much less time correcting, working less
and consuming less amperes. I have tested a new boat with a S1G
(Giro) and the XTE is les than 10 m all the time even with large
waves ...


Test it yourself ... It is better with a aparent wing angle betwen
45-60 off the bow but works up to 160 degrees very well, take ease
to not activate the interface unless you see that the boat ill turn in
the desired direction .... and avoid jibes ..... Good luck

Pascal

On 24 Feb., 00:46, "Pascal" wrote:
Well,

In my practical experience, when using the gps track mode (gps
interface ) with my autopilot St/4000 for several years, is that the
boat has much better tracking, with less yawing, staying much better
over the route and spending much less time correcting, working less
and consuming less amperes. I have tested a new boat with a S1G
(Giro) and the XTE is les than 10 m all the time even with large
waves ...

Test it yourself ... It is better with a aparent wing angle betwen
45-60 off the bow but works up to 160 degrees very well, take ease
to not activate the interface unless you see that the boat ill turn in
the desired direction .... and avoid jibes ..... Good luck

Pascal

Giro sounds good (hopefully cheaper than my boat), but S1G and XTE, I
don't know. I would be glad for some help with Brand Names, Types and
so.

Thanks Urs

On Feb 25, 5:18 pm, "muelec" wrote:
On 24 Feb., 00:46, "Pascal" wrote:

In my practical experience, when using the gps track mode (gps
interface ) with my autopilot St/4000 for several years, is that the
boat has much better tracking, with less yawing, staying much better
over the route and spending much less time correcting, working less
and consuming less amperes. I have tested a new boat with a S1G
(Giro) and the XTE is les than 10 m all the time even with large
waves ...

Test it yourself ... It is better with a aparent wing angle betwen
45-60 off the bow but works up to 160 degrees very well, take ease
to not activate the interface unless you see that the boat ill turn in
the desired direction .... and avoid jibes ..... Good luck

Pascal


don't know. I would be glad for some help with Brand Names, Types

Urs: Hi!

Does your ST1000 accept NMEA, only SeaTalk, or both SeaTalk and NMEA?

SeaTalk has simpler wiring and the ST of ST1000 stands for SeaTalk.
You might need to check the documentation with your ST1000 to see if
it can accept NMEA sentences. If your ST1000 can read NMEA sentences,
then you can use any brand of GPS. If you ST1000 can only read
SeaTalk, you might need to consider a Raymarine GPS or a NMEA-SeaTalk
interface.

I use an ST1000 (driving the trim tab to my rudder) or a ST4000
(driving my tiller) on a boat with displacement too heavy for the
ST1000 to drive the tiller.

I have wired my ST1000 into the boat's SeaTalk network, meaning that
the ST1000 can be used as a stand-alone (if the boat's electronics
have failed completely) or the ST1000 can steer using the GPS and
waypoint data from the ST4000 head (and the masthead wind instrument,
the water speed transducer, waypoints in the electronic charter, etc).

Using the full resources of the boat's navigational electronics, my
ST1000 does almost as good a job as the ST4000 (and the difference is
more likely due to the difference between driving the rudder directly
and driving only the rudder trim tab.

Hope this helps

Bil

On 25 Feb., 10:45, "Bil" wrote:
On Feb 25, 5:18 pm, "muelec" wrote:





On 24 Feb., 00:46, "Pascal" wrote:

In my practical experience, when using the gps track mode (gps
interface ) with my autopilot St/4000 for several years, is that the
boat has much better tracking, with less yawing, staying much better
over the route and spending much less time correcting, working less
and consuming less amperes. I have tested a new boat with a S1G
(Giro) and the XTE is les than 10 m all the time even with large
waves ...

Test it yourself ... It is better with a aparent wing angle betwen
45-60 off the bow but works up to 160 degrees very well, take ease
to not activate the interface unless you see that the boat ill turn in
the desired direction .... and avoid jibes ..... Good luck

Pascal

don't know. I would be glad for some help with Brand Names, Types

Urs: Hi!

Does your ST1000 accept NMEA, only SeaTalk, or both SeaTalk and NMEA?

SeaTalk has simpler wiring and the ST of ST1000 stands for SeaTalk.
You might need to check the documentation with your ST1000 to see if
it can accept NMEA sentences. If your ST1000 can read NMEA sentences,
then you can use any brand of GPS. If you ST1000 can only read
SeaTalk, you might need to consider a Raymarine GPS or a NMEA-SeaTalk
interface.

I use an ST1000 (driving the trim tab to my rudder) or a ST4000
(driving my tiller) on a boat with displacement too heavy for the
ST1000 to drive the tiller.

I have wired my ST1000 into the boat's SeaTalk network, meaning that
the ST1000 can be used as a stand-alone (if the boat's electronics
have failed completely) or the ST1000 can steer using the GPS and
waypoint data from the ST4000 head (and the masthead wind instrument,
the water speed transducer, waypoints in the electronic charter, etc).

Using the full resources of the boat's navigational electronics, my
ST1000 does almost as good a job as the ST4000 (and the difference is
more likely due to the difference between driving the rudder directly
and driving only the rudder trim tab.

Hope this helps

Bil- Zitierten Text ausblenden -

- Zitierten Text anzeigen -

Thank, this helps me a lot further.
My new ST1000Plus accepts NMEA. The question arrises now. What should
I buy next, so that the internal compass of the ST1000Plus ist not
used anymore, or gives me good steering in waves (on a 5m boat).
Giro, Windsensor or even only GPS?