Reply
 
Thread Tools Search this Thread Display Modes
 
Old 09-19-2020, 07:49 AM   #1
Guru
 
boomerang's Avatar
 
City: Kilmarnock VA
Country: united states
Vessel Name: YellowBird
Vessel Model: 1978 Mainship 34
Join Date: Apr 2016
Posts: 721
Autopilot to bow thruster interface needed?

Does anyone have any experience with an autopilot being interfaced to the bow thruster on a recreational boat? I understand the benefit of having the application on a larger vessel with a slow ROT but I'm wondering if it's practical or even needed on a smaller. more maneuverable boat.
While I've never owned a boat with a thruster, I've operated many that were equipped with them but never tested the ability to alter a heading while underway. On a smaller & faster boat, I would imagine that a bow thruster has a reduced effect, if any effect at all, while the boat is underway due to the lack of water in the tunnel.
I have a pretty long history regarding autopilots but I can honestly say I have never had the request (or need) to interface a pilot to a bow thruster since most of my work has been in the recreational sector 65' and under.
I'm posting the question because the owner of a Fleming 55 inquired about the feasibility of an interface and while my first response would be to say it wouldn't be necessary, I do want to try to make sure that I'm advising him correctly.
__________________
Advertisement

__________________
-Shawn-
boomerang is offline   Reply With Quote
Old 09-19-2020, 08:08 AM   #2
Guru
 
City: Rochester, NY
Country: USA
Vessel Name: Hour Glass
Vessel Model: Chris Craft Catalina 381
Join Date: Aug 2019
Posts: 2,262
I'd suggest to the owner to try activating the bow thruster manually in the situations where he thinks it would be beneficial to the autopilot. Then determine if it has enough effect to be worth the cost / effort of integrating it.

I'd also be curious what the owner expects to gain from the integration.
__________________

rslifkin is offline   Reply With Quote
Old 09-19-2020, 08:21 AM   #3
Guru
 
boomerang's Avatar
 
City: Kilmarnock VA
Country: united states
Vessel Name: YellowBird
Vessel Model: 1978 Mainship 34
Join Date: Apr 2016
Posts: 721
Quote:
Originally Posted by rslifkin View Post
I'd suggest to the owner to try activating the bow thruster manually in the situations where he thinks it would be beneficial to the autopilot. Then determine if it has enough effect to be worth the cost / effort of integrating it.

I'd also be curious what the owner expects to gain from the integration.
I could see where an interface might enhance the steering response at a very slow speed but personally, I wouldn't want my thruster grinding left and right all day long.
I feel it's something the owner is just curious about because it's advertised in the pilot literature but I don't see a huge advantage to it in his case.
__________________
-Shawn-
boomerang is offline   Reply With Quote
Old 09-19-2020, 08:23 AM   #4
Guru
 
menzies's Avatar
 
City: Jacksonville
Country: USA
Vessel Name: SONAS
Vessel Model: Grand Alaskan 53
Join Date: May 2014
Posts: 6,930
The suggestion seems to be using the AP in close quarters maneuvering, or using the thruster while cruising a waypoint.

Which neither is designed to do.
menzies is offline   Reply With Quote
Old 09-19-2020, 08:39 AM   #5
Guru
 
High Wire's Avatar
 
City: Cape May, NJ and Englewood, FL
Country: USA
Vessel Name: Irish Lady
Join Date: Dec 2007
Posts: 3,509
The higher the boat speed the less efficient the thruster becomes. Sorry absolutely no use to interface the two.
__________________
Archie
Irish Lady
1984 Monk 36 Hull #46
Currently in Englewood Florida.
High Wire is offline   Reply With Quote
Old 09-19-2020, 08:55 AM   #6
Guru
 
MYTraveler's Avatar
 
City: West Coast
Country: USA
Join Date: Apr 2014
Posts: 1,263
When I was figuring out how I wanted my boat equipped, I considered AP thruster control, but only in order to allow the AP to keep the bow pointed into the seas while stopped fishing offshore. Ultimately, I decided against it because it would have necessitated a hydraulic thruster and a more advanced (expensive) AP. I still regret that decision.
MYTraveler is offline   Reply With Quote
Old 09-19-2020, 09:14 AM   #7
Guru
 
boomerang's Avatar
 
City: Kilmarnock VA
Country: united states
Vessel Name: YellowBird
Vessel Model: 1978 Mainship 34
Join Date: Apr 2016
Posts: 721
Quote:
Originally Posted by MYTraveler View Post
When I was figuring out how I wanted my boat equipped, I considered AP thruster control, but only in order to allow the AP to keep the bow pointed into the seas while stopped fishing offshore. Ultimately, I decided against it because it would have necessitated a hydraulic thruster and a more advanced (expensive) AP. I still regret that decision.
Agreed, a sophisticated thruster/propulsion system would be a definite asset to someone like yourself who needs it to maintain a static position while fishing but I'm pretty confident with the boat I'm referring to here, the owner only uses the pilot to travel between points A & B. I will make sure he isn't interested in that type of a "skyhook" system but that would be an expensive upgrade, no doubt!
I do appreciate your experienced input.
__________________
-Shawn-
boomerang is offline   Reply With Quote
Old 09-19-2020, 09:36 AM   #8
Valued Technical Contributor
 
DavidM's Avatar
 
City: Litchfield, Ct
Country: USA
Join Date: Aug 2012
Posts: 5,556
Well, maybe your customer also would like a fully automated cruising system: Plug in your destination and engage, then sit back an enjoy your cocktail while the radar looks out for traffic, the electronic charts gives the system information to avoid rocks and when you get to your destination it communicates with the marina, finds its assigned slip automatically, backs in and contacts the marina guys to tie you up and hook up power and water.

You just sit back with your drink in hand and watch the world go by.

The automated system will also contact the Coast Guard to come rescue you when it goes sour.

David
DavidM is offline   Reply With Quote
Old 09-19-2020, 09:40 AM   #9
Guru
 
High Wire's Avatar
 
City: Cape May, NJ and Englewood, FL
Country: USA
Vessel Name: Irish Lady
Join Date: Dec 2007
Posts: 3,509
Quote:
Originally Posted by DavidM View Post
Well, maybe your customer also would like a fully automated cruising system: Plug in your destination and engage, then sit back an enjoy your cocktail while the radar looks out for traffic, the electronic charts gives the system information to avoid rocks and when you get to your destination it communicates with the marina, finds its assigned slip automatically, backs in and contacts the marina guys to tie you up and hook up power and water.

You just sit back with your drink in hand and watch the world go by.

The automated system will also contact the Coast Guard to come rescue you when it goes sour.

David
Its already out there in widespread use. Its called hiring a captain lol!!!
__________________
Archie
Irish Lady
1984 Monk 36 Hull #46
Currently in Englewood Florida.
High Wire is offline   Reply With Quote
Old 09-19-2020, 10:23 AM   #10
Guru
 
motion30's Avatar
 
Join Date: Jan 2010
Posts: 1,017
I had a 34-ft marine trader. And the ow thruster had virtually no effects at anything over idle speed. Not the conditions where you would engage on autopilot. I cannot speak for larger boats
motion30 is offline   Reply With Quote
Old 09-19-2020, 10:36 AM   #11
Guru
 
ScottC's Avatar
 
City: Malm
Country: SWEDEN
Vessel Name: ABsolutely FABulous
Vessel Model: Greenline 33 Hybrid (2010)
Join Date: Nov 2019
Posts: 625
I wonder what your contact sees as the "use case" for using a thruster while under way, regardless of whether it's interfaced with the auto pilot or not.



Personally, I can't imagine any benefit from this. I only see it as added complexity and cost...and another interface to fail when some device manufacturer decides to upgrade its software without testing all possible -- and unlikely -- scenarios.


To be of any benefit, he would have to be going dead slow, as already stated above and it would have to be very calm, otherwise the bow thruster risks sucking air between the wavelets. It also seems to me that this would be an unkind system design for the battery having to supply the power to the thruster. I think a premature death of this battery would likely be in the cards.
__________________
Scott
2010 Greenline 33' Hull #54
Home port: Malm, SWEDEN
Currently in: Gruissan, FRANCE
ScottC is offline   Reply With Quote
Old 09-21-2020, 06:33 AM   #12
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 20,981
Most electric thrusters have a very limited operating time.

Even if it worked to steer the total on time might be far above what the unit is built for.

A hyd thruster might survive better.
FF is offline   Reply With Quote
Old 09-21-2020, 08:56 AM   #13
Guru
 
psneeld's Avatar
 
City: AICW
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 22,188
Underway is one thing, at idle or rest is similar to dynamic positioning...

....but my guess is if that's the goal, design parameters have to be met for that purpose....modifying may be impractical.
psneeld is offline   Reply With Quote
Old 09-21-2020, 09:17 AM   #14
Guru
 
mvweebles's Avatar
 
City: Saint Petersburg
Country: United States
Vessel Name: Weebles
Vessel Model: 1970 Willard 36 Trawler
Join Date: Mar 2019
Posts: 1,503
Bow thruster is absolutely worthless at anything above slow marina speeds. Imagine standing next to a parked car and pushing yourself away. Now imagine the car is moving at 20 mph and you try to push-off. Energy goes all over, very little (if any) in the direction you want.

Peter
__________________
M/V Weebles
1970 Willard 36 Sedan Trawler
Current Location: Ensenada MX
mvweebles is online now   Reply With Quote
Old 09-21-2020, 10:02 AM   #15
Veteran Member
 
DrissZougari's Avatar
 
City: Cypress Landing Marina
Country: North Carolina
Vessel Name: BZ interlude
Vessel Model: MS390
Join Date: Mar 2019
Posts: 74
I think this member is confusing the integration of AP and Thrusters to Engines and Thrusters used for docking a boat ( like idock system or Easy Docking system)
DrissZougari is offline   Reply With Quote
Old 09-21-2020, 10:14 AM   #16
Guru
 
LarryM's Avatar
 
City: League City, TX
Country: USA
Vessel Name: Pelago
Vessel Model: Wellcraft 3300 Coastal
Join Date: Aug 2011
Posts: 989
Certain Simrad autopilots (AP25 and AP50 families and later I presume) have offered a Thruster Interface. It provides a control signal to a thruster by either on/off solenoid, continuous control (voltage or current), proportional directional control or Sauer Danfoss PVEM valve. The thruster output signal is calculated in the TI (Thruster Interface) based on mode and heading information received from the Control Unit and other system units on the network.

Its function is to supplement the rudder(s) in maintaining the vessel's AP selected heading at any speed below 6 kts. As speed falls off and rudder authority is lost, the thruster proportionally provides additional correction. The FU or NFU steering levers if present, can also be used to control the thruster directly with a button push.

It can be useful in when anchoring, station-keeping, docking or during low speed vessel operation, particularly when shorthanded.

I've used one in the past and found it was a 'nice to have' optional feature, but certainly not a necessity.
__________________
Larry
M/V Pelago
LarryM is online now   Reply With Quote
Old 09-21-2020, 08:45 PM   #17
Guru
 
JDCAVE's Avatar
 
City: Lions Bay, BC
Country: Canada
Vessel Name: Phoenix Hunter
Vessel Model: Kadey Krogen 42 (1985)
Join Date: Apr 2011
Posts: 2,428
Quote:
Originally Posted by LarryM View Post
It can be useful in when anchoring, station-keeping, docking...

The last think Id want is having the autopilot engaged whilst docking...especially with the AP having control of the thruster...

Jim
JDCAVE is offline   Reply With Quote
Old 09-21-2020, 08:46 PM   #18
Guru
 
motion30's Avatar
 
Join Date: Jan 2010
Posts: 1,017
Quote:
Originally Posted by JDCAVE View Post
The last think Id want is having the autopilot engaged whilst docking...especially with the AP having control of the thruster...

Jim
That's what I was thinking as well
motion30 is offline   Reply With Quote
Old 09-22-2020, 09:37 AM   #19
Guru
 
LarryM's Avatar
 
City: League City, TX
Country: USA
Vessel Name: Pelago
Vessel Model: Wellcraft 3300 Coastal
Join Date: Aug 2011
Posts: 989
Quote:
Originally Posted by JDCAVE View Post
The last think Id want is having the autopilot engaged whilst docking...especially with the AP having control of the thruster...

Jim
Jim, agreed, the use when docking is probably very limited. I saw it used to hold a workboat parallel to finger pier in a crosswind while docking. The solo captain secured the stern line and the TI kept the high bow from being blown away from the pier while he secured a mid-ship brest and so on. The boat was otherwise stopped. He used it more like you might use a remote thruster control. The corrections from the thruster seemed measured and proportional.
__________________
Larry
M/V Pelago
LarryM is online now   Reply With Quote
Old 09-22-2020, 07:14 PM   #20
Guru
 
wkearney99's Avatar
 
City: Bethesda, MD
Country: USA
Vessel Name: Solstice
Vessel Model: Grand Banks 47 Eastbay FB
Join Date: Feb 2018
Posts: 1,422
Quote:
Originally Posted by MYTraveler View Post
When I was figuring out how I wanted my boat equipped, I considered AP thruster control, but only in order to allow the AP to keep the bow pointed into the seas while stopped fishing offshore. Ultimately, I decided against it because it would have necessitated a hydraulic thruster and a more advanced (expensive) AP. I still regret that decision.
This is the one scenario I wouldn't have considered. I certainly wouldn't want it with an electric thruster, but a hydraulic one driven off the engine(s).. for your fishing scenario it'd certainly be interesting. Couple it with a satellite compass and you'd kinda of have a poor man's version of the drift heading feature in modern pod setups. (as in, keep me pointed toward X degrees while drifting).
__________________

__________________
-- Bill Kearney
2005 Eastbay 47 FB - Solstice
wkearney99 is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 11:19 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012
×