"Roger Long" wrote:

"Jere Lull" wrote

I'm SO glad I don't have to pay those fuel bills.

I see by the address in your signature file that you will be. Don't worry
though. It's not as bad as it looks. Full speed operation is limited to
10% of operation by engine rating and the boat will spend most of it's
cruising time burning about half of that. Most of it's overall time will be
spent on scientific station burning just 5 - 10 GPH.

BTW, it's also one of the smallest vessels in the world to have dynamic
positioning. Give it a command and it will stay within a couple meters of a
spot over the bottom and maintain heading. Yesterday, I watched it back
slowly up to a buoy to the position where it could be attached to the
A-frame in a 25 knot wind. This was under completely automatic control while
we just stood and watched. It then stopped at the right point and just sat
there. The autopilot is part of the DPS system which is connected to the
LAN and the satellite Internet so, with the several video cameras on board,
you could literally sit at your computer on land and drive it around with no
one aboard.

Very cool.

Good feeling, isn't it, when it all works right. Congratulations!


Michael Porter Marine Design
mporter at mp-marine dot com
www.mp-marine.com
** Posted from http://www.teranews.com **

"Michael Porter" wrote

Good feeling, isn't it, when it all works right. Congratulations!


Thanks.

Way back when I first laid out the rough idea, we based our operating cost
projections on the maximum continuous horsepower for the engine (80%) and
half fuel on the theory that they would always go as fast as possible in
transit. The fuel curves just came back yesterday and that turns out to be
the best fuel economy speed (mileage) and she goes 1.5 knots faster than I
promised when we settled on the preliminary design.

We got the dynamic positioning system fully installed and demonstrated
yesterday and it is amazing. In DP maneuvering mode with the joy stick, you
can steer straight down a narrow channel. If you got too close to one side,
you just push the joystick sideways and the boat moves that direction
without changing heading. To change heading, twist the joy stick. To dock,
just pull up sideways to the space, stop, push the joystick over, and she
goes straight in sideways. Push a button and she stays in one spon within
3 - 6 feet and 1 - 2 degrees of heading while the shore line handlers amble
down from the shop. Punch in a closing speed and offset, and she moves into
the dock while you stand their with your hands in your pocket and then
stops. Docking single handed in up to 20 knot winds and just stepping
ashore to handle the lines would be perfectly feasible although someone
ought to be at the controls in case of system failure.

The DP techs believe this is the smallest DP vessel in the world in
displacement. There are a couple of shorter ones (one also of my design)
but they are much heavier displacement vessels.

Tours will not be given to powerboaters because they don't want to have to
wipe the drool off the consoles.

--
Roger Long