Boat bow and stern thrusters

I would like to put homemade bow and stern thrusters on by 28 foot boat. I plan to buy used trolling motors; cut handles off; mount to homemade aluminum brackets directed port-starboard.

Here is what I envision:
- 12 volt system
- An 8 position joy stick.
Reference directions North South East West NE SE SW NW.
For now N S are not used, in a future version I might mount a second motor on stern directed bow-stern and use them.
- One relay at bow and one at stern. Each relay takes two control lines and can switch positive or negative on the trolling motors for forward or reverse.
- An on/off toggle "reverse switch" which causes the thrusters to go in opposite directions to double up the turning force.

I would like the joystick to control the bow and stern thrusters as shown below:

West - both thrusters to port
East - both thrusters to starboard
NW - bow thruster to port
SW - stern thruster to port
NE - bow thruster to starboard
SE - stern thruster to starboard

With reverse switch (RS) on:
NW - bow thruster to port; stern thruster to starboard
SW - stern thruster to port; bow thruster to starboard
NE - bow thruster to starboard; stern thruster to port
SE - stern thruster to starboard; bow thruster to port

Logic table
Control Lines
Joystick Bow Stern
N S E W NW SW NE SE RS Port Starboard Port Starboard
1 0/1 0/0 0/0 0/0 0/0
1 0/1 0/0 0/0 0/0 0/0
1 0/1 1/1 0/0 1/1 0/0
1 0/1 0/0 1/1 0/0 1/1
1 0/1 1/1 0/0 0/0 0/1
1 0/1 0/0 0/1 1/1 0/0
1 0/1 0/0 1/1 0/1 0/0
1 0/1 0/1 0/0 0/0 1/1

As above there are nine input lines and four output lines. What is the simplest way to implement the control logic?

Thanks for reading.
Mike

 

[Tim Wescott]

On Sun, 31 Jan 2016 21:01:58 -0800, rh5680 wrote:

I would like to put homemade bow and stern thrusters on by 28 foot boat.
I plan to buy used trolling motors; cut handles off; mount to homemade
aluminum brackets directed port-starboard.

Here is what I envision:
- 12 volt system - An 8 position joy stick.
Reference directions North South East West NE SE SW NW.
For now N S are not used, in a future version I might mount a second
motor on stern directed bow-stern and use them.
- One relay at bow and one at stern. Each relay takes two control lines
and can switch positive or negative on the trolling motors for forward
or reverse.
- An on/off toggle "reverse switch" which causes the thrusters to go in
opposite directions to double up the turning force.

I would like the joystick to control the bow and stern thrusters as
shown below:

West - both thrusters to port East - both thrusters to starboard NW -
bow thruster to port SW - stern thruster to port NE - bow thruster to
starboard SE - stern thruster to starboard

With reverse switch (RS) on:
NW - bow thruster to port; stern thruster to starboard SW - stern
thruster to port; bow thruster to starboard NE - bow thruster to
starboard; stern thruster to port SE - stern thruster to starboard; bow
thruster to port

Logic table
Control Lines
Joystick Bow Stern N S E W NW SW
NE SE RS Port Starboard Port Starboard 1
0/1 0/0 0/0 0/0 0/0
1 0/1 0/0 0/0 0/0 0/0
1 0/1 1/1 0/0 1/1 0/0
1 0/1 0/0 1/1 0/0 1/1
1 0/1 1/1 0/0 0/0 0/1
1 0/1 0/0 0/1 1/1 0/0
1 0/1 0/0 1/1 0/1 0/0
1 0/1 0/1 0/0 0/0 1/1

As above there are nine input lines and four output lines. What is the
simplest way to implement the control logic?

Thanks for reading.
Mike

Why bother with a reverse switch?

The simplest way to do this, assuming the joystick can carry enough
current to actuate a relay, is to run a diode from the relevant joystick
to the relevant relay for each "1" in your table, supply the joystick
with 12 volts, and ground the relay coils on the other end. Some sort of
RC snubber in the joystick may or may not be called for, to keep the
inductive kick of the relays from damaging your diodes.



--
www.wescottdesign.com

 

[John Larkin]

On Sun, 31 Jan 2016 21:01:58 -0800 (PST), rh5680@yahoo.com wrote:

I would like to put homemade bow and stern thrusters on by 28 foot boat. I plan to buy used trolling motors; cut handles off; mount to homemade aluminum brackets directed port-starboard.

Here is what I envision:
- 12 volt system
- An 8 position joy stick.
Reference directions North South East West NE SE SW NW.
For now N S are not used, in a future version I might mount a second motor on stern directed bow-stern and use them.
- One relay at bow and one at stern. Each relay takes two control lines and can switch positive or negative on the trolling motors for forward or reverse.
- An on/off toggle "reverse switch" which causes the thrusters to go in opposite directions to double up the turning force.

I would like the joystick to control the bow and stern thrusters as shown below:

West - both thrusters to port
East - both thrusters to starboard
NW - bow thruster to port
SW - stern thruster to port
NE - bow thruster to starboard
SE - stern thruster to starboard

With reverse switch (RS) on:
NW - bow thruster to port; stern thruster to starboard
SW - stern thruster to port; bow thruster to starboard
NE - bow thruster to starboard; stern thruster to port
SE - stern thruster to starboard; bow thruster to port

Logic table
Control Lines
Joystick Bow Stern
N S E W NW SW NE SE RS Port Starboard Port Starboard
1 0/1 0/0 0/0 0/0 0/0
1 0/1 0/0 0/0 0/0 0/0
1 0/1 1/1 0/0 1/1 0/0
1 0/1 0/0 1/1 0/0 1/1
1 0/1 1/1 0/0 0/0 0/1
1 0/1 0/0 0/1 1/1 0/0
1 0/1 0/0 1/1 0/1 0/0
1 0/1 0/1 0/0 0/0 1/1

As above there are nine input lines and four output lines. What is the simplest way to implement the control logic?

Thanks for reading.
Mike

Why not just two DPDT center-off toggle switches? No logic needed.
That can do any combination of drives, and it would be intuitive and
easy to get used to.




--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[Jasen Betts]

On 2016-02-01, rh5680@yahoo.com <rh5680@yahoo.com> wrote:

I would like to put homemade bow and stern thrusters on by 28 foot boat. I plan to buy used trolling motors; cut handles off; mount to homemade aluminum brackets directed port-starboard.

Here is what I envision:
- 12 volt system
- An 8 position joy stick.
Reference directions North South East West NE SE SW NW.
For now N S are not used, in a future version I might mount a second motor on stern directed bow-stern and use them.
- One relay at bow and one at stern. Each relay takes two control lines and can switch positive or negative on the trolling motors for forward or reverse.
- An on/off toggle "reverse switch" which causes the thrusters to go in opposite directions to double up the turning force.

I would like the joystick to control the bow and stern thrusters as shown below:

West - both thrusters to port
East - both thrusters to starboard
NW - bow thruster to port
SW - stern thruster to port
NE - bow thruster to starboard
SE - stern thruster to starboard

A typical joystick has 4 output lines (usually called forwards, back, left, right)
mount it rotated 45 degrees. NW and NE switches control the bow thruster
the SW and SE control the stern.

With reverse switch (RS) on:
NW - bow thruster to port; stern thruster to starboard
SW - stern thruster to port; bow thruster to starboard
NE - bow thruster to starboard; stern thruster to port
SE - stern thruster to starboard; bow thruster to port

The reverse switch conects the opposite switches on the joystick, (use a
DPST switch) If you want east and west to function as before it's a bit trickier.

> As above there are nine input lines and four output lines. What is the simplest way to implement the control logic?

there aren't, and don't.

assuming theses are brush motors the


--
\_(ツ)_

 

[George Herold]

On Monday, February 1, 2016 at 12:02:03 AM UTC-5, rh5...@yahoo.com wrote:

I would like to put homemade bow and stern thrusters on by 28 foot boat. I plan to buy used trolling motors; cut handles off; mount to homemade aluminum brackets directed port-starboard.

Here is what I envision:
- 12 volt system
- An 8 position joy stick.
Reference directions North South East West NE SE SW NW.
For now N S are not used, in a future version I might mount a second motor on stern directed bow-stern and use them.
- One relay at bow and one at stern. Each relay takes two control lines and can switch positive or negative on the trolling motors for forward or reverse.
- An on/off toggle "reverse switch" which causes the thrusters to go in opposite directions to double up the turning force.

I would like the joystick to control the bow and stern thrusters as shown below:

Sorry, how many trolling motors? And which direction are they pointed?
Are you going to be cruising around with a regular outboard motor too?
(I might be afraid of breaking the props on the trolling motor.)
Have you ever "driven" your boat with just the trolling motor?
(PITA, in my experience.)

George H.

West - both thrusters to port
East - both thrusters to starboard
NW - bow thruster to port
SW - stern thruster to port
NE - bow thruster to starboard
SE - stern thruster to starboard

With reverse switch (RS) on:
NW - bow thruster to port; stern thruster to starboard
SW - stern thruster to port; bow thruster to starboard
NE - bow thruster to starboard; stern thruster to port
SE - stern thruster to starboard; bow thruster to port

Logic table
Control Lines
Joystick Bow Stern
N S E W NW SW NE SE RS Port Starboard Port Starboard
1 0/1 0/0 0/0 0/0 0/0
1 0/1 0/0 0/0 0/0 0/0
1 0/1 1/1 0/0 1/1 0/0
1 0/1 0/0 1/1 0/0 1/1
1 0/1 1/1 0/0 0/0 0/1
1 0/1 0/0 0/1 1/1 0/0
1 0/1 0/0 1/1 0/1 0/0
1 0/1 0/1 0/0 0/0 1/1

As above there are nine input lines and four output lines. What is the simplest way to implement the control logic?

Thanks for reading.
Mike

 

[default]

On Sun, 31 Jan 2016 21:01:58 -0800 (PST), rh5680@yahoo.com wrote:

I would like to put homemade bow and stern thrusters on by 28 foot boat. I plan to buy used trolling motors; cut handles off; mount to homemade aluminum brackets directed port-starboard.

Here is what I envision:
- 12 volt system
- An 8 position joy stick.
Reference directions North South East West NE SE SW NW.
For now N S are not used, in a future version I might mount a second motor on stern directed bow-stern and use them.
- One relay at bow and one at stern. Each relay takes two control lines and can switch positive or negative on the trolling motors for forward or reverse.
- An on/off toggle "reverse switch" which causes the thrusters to go in opposite directions to double up the turning force.

I would like the joystick to control the bow and stern thrusters as shown below:

West - both thrusters to port
East - both thrusters to starboard
NW - bow thruster to port
SW - stern thruster to port
NE - bow thruster to starboard
SE - stern thruster to starboard

With reverse switch (RS) on:
NW - bow thruster to port; stern thruster to starboard
SW - stern thruster to port; bow thruster to starboard
NE - bow thruster to starboard; stern thruster to port
SE - stern thruster to starboard; bow thruster to port

Logic table
Control Lines
Joystick Bow Stern
N S E W NW SW NE SE RS Port Starboard Port Starboard
1 0/1 0/0 0/0 0/0 0/0
1 0/1 0/0 0/0 0/0 0/0
1 0/1 1/1 0/0 1/1 0/0
1 0/1 0/0 1/1 0/0 1/1
1 0/1 1/1 0/0 0/0 0/1
1 0/1 0/0 0/1 1/1 0/0
1 0/1 0/0 1/1 0/1 0/0
1 0/1 0/1 0/0 0/0 1/1

As above there are nine input lines and four output lines. What is the simplest way to implement the control logic?

Thanks for reading.
Mike

In theory it should work. It isn't like there's enough thrust there
to horse a 48 footer around with impunity and you'd have plenty of
time to change directions as the boat came up on the pier (whatever).

What would make me reconsider it would be the physical modifications
to the boat. One assumes you haven't already got built-in, sealed,
and reinforced tunnels for the thrusters. Installing that is a
monumental undertaking IMO.

What will that do to your cruising speed? You can't just open a few
holes in the hull and expect the hydrodynamic characteristics of the
hull to remain the same.

This is a displacement hull? Sail, barge, houseboat, etc.(one
hopes..)

Trolling motors are designed on the cheap. Immersed 24/7 might be
death to the motors, so make them easy to change out and leave the
mounting so you're not locked into only one size/brand.

I know one guy that buys cheap junkyard automobile ventilation or
heater core motors and uses them as trolling motors and he says he
comes out ahead if he only gets one fishing trip per motor. The motor
is immersed in salt water and gets a spray down with WD-40 and may go
two trips before it has to be replaced.

You may do better with something like those hull de-icer motor/props
they are usually in a can filled with oil and designed to take a lot
of abuse. (but don't provide a lot of thrust)

I don't know what your boat is worth and what emotional attachment you
may have to it... but I'd get an opinion from a yard before I started
hacking into the hull....

I paddle my kayak (I have a large sailboat too) on the Cape Fear and
can see the barges they use. A utility pusher drives into a socket on
the barge and connects to the thrusters built into the barge. When
the barges are sitting empty I can look (can almost paddle the kayak
through) the thruster tunnels. A hellovalot of engineering goes into
those things. If it were me, I pay the extra bucks and get thrusters
installed by a yard BUT ONLY IF THE HULL CHARACTERISTICS could work
well with large holes and the turbulence that would cause.

They use hydraulic motors for commercial barge thrusters and that
gives them lots of power and control and the motors are damn near
bullet-proof without being built specifically for marine use. They
look like ordinary hydraulic motors with a heavy coating of epoxy
paint on them.