We are working on a seastead design.
The design goals are discussed at http://seastead.ai/ai/seastead.goals.html
This is NOT a normal boat hull shape, but it is a bit like a trimaran in that their are 3 floats.


Above the water there will be a big triangle frame, 80 feet front to back and 40 feet wide.
The triangle frame will be a sort of truss structure that also doubles as a 4 foot high railing to keep humans from falling off.
We will call the 3 points on the triangle "front", "left", and "right".
And the edge between left and right we will call "back".

There will be a floor and roof/ceiling (7 foot inside) the full area of the triangle but only the center 14 feet will be enclosed living space,
the sides will be open porch.  
The living area will have lots of windows in the font and back and some along the side.    

There will be 3 floats/legs/wings that will be the buoyancy.
Each leg/wing will 19 feet long and have a NACA foil shape with 10 foot chord and 3 foot width.
This makes for a "small waterline area" similar like a small oil platform but one that can move through the water easier because of the foil shape.
Each of the 3 legs will be attached to the underside of the big triangle near one of the 3 points and going down into the water.
The 3 wings will all be parallel with the blunt or "leading edge of the wing" forward  so it is easy for the seastead to move forward.
Each leg will be 50% under the water (so 0.5 * 19 feet) and the top 50% out of the water.
On front of each leg on the top half that is out of the water will be a built in ladder.

There will be 6 RIM drive thrusters, one on each side of the legs/wings about 3 feet up from the bottom.
These will be aimed so they can push water past the wing and toward the back of the seastead.

There are 3 stabilizers that look like a little airplanes, one attached near the back of each main seastead leg.  
The little airplane's wings are 10 feet wide (wing span) and 1 foot front to back (chord), the body 6 feet long, and the elevator 2 feet wide.
A small actuator will be able to make the elevator on this airplane angle up or down so it can adjust the angle of 
attack of the main wing of this stabilizer airplane without the need of a large actuator.
While the thick part of the leg is 4 feet wide the back where the airplane will attach is very thin.  And to get the airplane's
center of lift to balance on the pivot only about notch into about 1/4 of the front/center of the wing is needed.


On top of the roof there will be solar all over.

Centered on outdoor space on the left side of the living area will be a 14 foot RIB boat with 1 outboard motor.   
On the triangle frame next to the boat will be a davit/crane for loading and unloading the boat.
This davit/crane will be shorter, like 6 feet, so it can swing under the roof.



We will use Marine Aluminum.
The pieces can all fit in 40 foot containers, so shipping is reasonable, and assembled in a shipyard.


Estimate the total "installed watts" and the kwh per average Caribbean day.
Lets say we have 500 kwh of LiFePO4 batteries.
How heavy would the batteries be?  Assume the cost will be $90/kwh, what would the total cost be?
We would split this weight among the 3 floats, keeping weight wide increases rotational inertia
and so reduces motion from waves.  The weight of the triangle frame is widely spread so also has great rotational inertia.
If we used a days worth of average energy production evenly over a 24 hour period how many watts would we have?

We will have 3 separate solar/charge-controller/battery/inverter systems so a problem with one
does not leave seastead without power.  Can have connections between them with breakers to isolate in case of trouble.

Imagine we are in high winds and turn the seastead to point into the wind.  What sort of 
drag would we have for 30, 40, 50 MPH winds and how many watts would it take for our
propellers to hold the seastead stationary?

Now imagine that we use the 3 wings like keels or dagger-boards and aim across the wind and just a little bit up.
How most of the wind force gets transferred to the wing/keel/dagger-board.
In this way how much wind do you think this design could still keep control in?

For a normal day in the Caribbean estimate the average watts power draw of all electrical components.
How much percent extra solar power do we have?

If we use the "extra power" to run the thrusters what cruising speed could we maintain for 24 hours/day?

Please make a table showing values for with stabilizer on and also when off for each of the values 4, 5, 6, 7, 8 knots,
if we just started with full batteries but got no more solar, many hours and statute miles the seastead could go.


Imagine we get a company in China to make the body and legs, and probably get other parts from there as well.

Please estimate weight and cost for each of these:
 1) legs
 2) body
 4) 6 RIM drive thrusters
 6) solar panels 
 7) solar charge controllers 
 8) batteries
 9) inverters
 10) 2 water makers and water storage
 11) air conditioning (AC) - maybe 3 units for 3 rooms but only using 1 at a time 
 12) insulation
 13) flooring, cabinets, kitchen stuff, furniture, bathrooms, bedroom
 14) waste tanks
 15) glass and glass doors at ends
 16) refrigerator
 17) davit/crane/winch to lift dinghy out of the water
 18) safety equipment
 19) dinghy
 20) 2 sea anchors 
 21) kite for propulsion.  Can use as backup, fun, or extra speed - perhaps stack 20 kites of 6 foot each 
 22) 8 air bags in each leg so for extra safety in case of leak in leg
 23) 2 Starlink  - need a backup
 24) trash compactor
 25) 3 aluminum airplane stabilizers with small actuator
 26) anything else to finish it out

Also totals for weight and cost.  

Estimate the Natural Roll Period for tolling side to side and also for pitching front to back.
Estimate how much damping this shape gives per roll side to side and then also pitching front to back.

Please estimate for both 6 and 7 knots:
   1) how much the body would tip in terms of feet higher or lower between front and back of living area
   2) Gs felt due to waves in living area spot located at the center of the triangle 

for the following types of waves:
  1) 3 feet 3 second period
  2) 5 feet 5 second period
  3) 7 feet 7 second period

both if the wave is coming from the front and also if it is coming from the side and
if the stabilizers are on or off.

What length catamaran would have comparable inside square footage to this seastead?
About how many times the cost would that catamaran be compared to this seastead?
Would you agree that this seastead will pitch and roll less in 7 foot waves than a 100 foot catamaran?


In flag of convenience countries like Panama and Liberia could we register this as a "trimaran yacht" or
would it be harder than that? 

FEEDBACK
Also feel free to give any general feedback on:
  1) viability of current concept as a profitable business product
  2) how concept might be improved
  3) how big a market niche this first product could become
  4) Do you think this is fast enough that with weather forecast accuracy in 2028 we should be reasonably
     safe from storms in the Caribbean if we are at the southern edge during hurricane season?
  5) Are there single points of failure that you think need to be further addressed or is what we have good?

Summary section.
  For a summary at the end please list:
    1) estimated total cost for first unit and cost each if we ordered 20
    2) average solar produced, average solar used not counting propulsion, average power left for propulsion
    3) lbs extra buoyancy for customers and their personal stuff
    4) speed in MPH this design can average 24/7 in Caribbean