I have uploaded a video (to YouTube) of the rudder mechanism on Hull #1
working from end-stop to end-stop.
(Excuse the video quality, I used my phone to record it.)
I connected an
if you want to know) and a
stepper controller to
the stepper motor which drives the rudder.
I wanted to exercise the tiller gears and the rudder shaft for a while.
The video shows the rudder swinging from almost completely to Starboard,
all the way back to Port.
Hull #002 is coming along, slowly.
The stations are mounted on the strongback and I’ve been double-checking the alignment.
I have time to do this because 1/32nd inch balsa wood is hard to come by,
and because I haven’t cut the keelson yet.
Well, I have, but I need to re-cut it.
The original was cut to the wrong profile.
While the work on hull 2 continues,
I’ve been using Hull #001 to test out aspects of the boat design
and control systems.
In fact, I am very close to launching the hull…
I have discussed the hull construction process in earlier posts, which you can find via
the above search bar.
To recap, you take the hull design and “loft” the shape of each section or bulkhead,
from the drawing.
You then cut this out of 6mm marine ply (or equivalent), mount each of the stations onto
a strongback, and now you have something which forms the shape.
I also need to add a keelson to the picture.
A keelson is a long, keel-like piece of wood which runs from stem to
stern, connecting the bulkheads.
I cut one already but it turned out to be too short due to a miscalculation
on my part.
Generally I cut a thin (about 2cm wide) outline of the keel of the boat,
from a sheet of ply.
According to the calendar, it is now 963 days
since my last blog posting on here.
A lot has happened in that thirty month period,
but not a lot in terms of the robotic boat.
I’ve worked on a variety of designs of winged sail
and I think I have a design which will work really
More about that, anon.
You may also notice I redesigned the blog, and
I had originally planned to code a
Ruby on Rails
and this is mostly why there haven’t been any blog updates
for the last couple of years.
I wanted to incorporate automatic blog updates from the
boat when she’s at sea, but trying to decide on a layout
for the new blog was like trying to choose the paint
colour for the bike shed.
Eventually I just went with Jekyll as it allows me to
have boat updates, and doesn’t involve spending months
tweaking HTML and CSS.
The big news though is a decision I made last year,
to switch away from my own hull design,
which you can find
Chatting with Professor Paul Miller of the US Naval Academy,
I came to the conclusion that the design he and his students had
perfected, which they call the
My original plan was to use a traditional mast and mainsail, with
Yannick Lemonnier of
volunteering to produce the sail.
Yannick is no stranger to mad schemes himself,
having competed in far too many
These days, he spends his time sailing his Moth winged-beast, or racing
his International 14.
That is, when he’s not making sails for everyone from Beoga Beag to
the Volvo Open 70s.
Due to other, exciting distractions (which I will mention in a later post),
I haven’t had a chance to keep the blog up to date.
Still, work progresses on the boat, and that’s the important part.
Last month, with the keel now in its new position about 30mm further back along the hull,
and sealed into place, it was time to add the electronics board.
Here’s a quick sneak picture of the hull with the wiring harness complete and the decks sealed in place.
The keel is still only temporarily installed so the main compartment is again flooding with sea water.
The bow is still slightly down in comparison to the stern,
but this is mostly due to the flooded compartment.
Also, the keel still hasn’t been moved back, yet.
That will happen this week.
The solar power connector and the masthead connector are
visible just in front of the main compartment.
The ugly brown tape is to seal up the deck fittings for the
rudder and sail servo motors.
The deck plates are taped to the hull using polyester
resin and fibreglass tape.
They need to be sanded smooth, ready for another final
coat of epoxy and then a generous layer of antifoul.
The antifoul coating will be one of the very last steps
prior to the Microtransat.
If you look at the previous blog posting on the SGS,
the alu plate which supports the electronics will be mounted
over the main compartment and secured in place.
A quick look at the almost-complete Sailboat Guidance System (SGS).
The board on the left is Igor.
Otto is on the right, and the main CPU (Mother) is hidden underneath.
The ribbon cable brings all the I/O to and from the boards.
The red insulating tape is to remind me of some of the last remaining wires which need to be connected.
You can also just about make out the DC/DC converter which is just underneath the ribbon cable at the bottom of the picture.
On September 1st, we launched the hull in Aughinish bay, without sails, rudder or electronics.
The purpose was to see how the hull performed in open water, with the keel attached.
As the keel wasn’t properly attached or sealed in place,
the main compartment flooded with water,
but as the compartments are individually water-tight, this wasn’t an issue.
It did lower the boat in the water somewhat, but not to any significant degree.
As the compartment wiring wasn’t completed,
and the deck panels weren’t glassed in place,
they were attached to the hull using duct tape.
Not pretty, but it works.
After a lunchtime conversation with a friend of mine,
I ditched some of the earlier design considerations
around message-passing and MQ-based systems in favour of the NoSQL database
Redis is an open source, BSD licensed, advanced key-value store.
It is often referred to as a data structure server since keys can contain strings,
hashes, lists, sets and sorted sets.
That’s according to the official blurb on the web site, at least.
It has several interesting components which are useful for Beoga Beag.
It has a rudimentary pub/sub architecture pattern, it is extremely lightweight,
it stores its database in memory rather than on a disk (so it’s less likely
to burn through the Compact Flash file system),
and it has an “append-only file” (AOF) archive mechanism.