Hi PICAXE Folks. This is only for radio amateurs (HAMs) among you - and I know there are a few.
I've just posted it onto the Microtransat forum - sorry not a link but a mailing list of participating
teams around the World. To know more, follow the Microtransat link from my page.
Maybe someone can build and "operate" a WSPR solution soon ?
Maybe the (radio HAM) rules permiit their callsign to be used for more than one boat and team.
Robin
Hi Folks. Later this week I may have a very low cost, simple and reliable
autopilot solution working, based upon little more than a GPS, PICAXE and rudder servo.
I'll put more onto my robot boat page later this week.
www.gpss.co.uk/autop.htm
This was partly prompted by recent conversations with the Aberystwyth team,
in which I said I might bring along one of our boats to view, but not compete.
I must admit, it would be nice to have something, based on what I already have,
which might be reliable enough to survive a few months at sea, and MIGHT get there.
More about the boat and simple autopilot later this week.
The reason for this posting is how I can do the long range tracking.
Our recent BBC bottle tracking was great fun - but not relevant:
www.gpss.co.uk/bbcbot.htm
Although there has been some spin-off like modelling of tides, etc, electronic components, etc.
Today I had a chat Roger, my local radio amatuer (HAM) friend, about WSPR, and I'm also
discussing this with Klaus. Both are on my old (1999) radio page
www.gpss.co.uk/radio.htm
with a few words added today, and links to WSPR (on Wiki) and my robot boat page above.
I hope you like my choice of picture - the relaunch of Snoopy Sloop 4 with a "casual throw"
What is the minimum accuracy to qualify for the daily (or more often) position reports ?
I guess 1 degree of lat and lon might not be enough ? i.e. within 100 miles ?
Would 1 minute of lat and lon be good enough ? Nearer 1 mile precision ?
This effects the details of how WSPR message is used to carry the GPS lat/lon position.
Maybe there are some radio HAMs out there among you. Sadly my friend Roger may be able
to help me in the longer term (e.g. next year) but not in the next week or two.
From our discussion - and the few words now on that radio page above - it seems
that a WSPR based solution could be put together by a knowledgeable radio HAM,
for the cost of just a few tens of pounds Sterling. But this GPS-WSPR transmitter
on the boat(s) would need to be "operated" by that same HAM, using his callsign.
This also has to be done carefully within the rules, and may need formal approval.
The big benifit is not just the low cost of transmitter hardware: it is that the transmissions
will be picked up by the massive number of HAMs around the World, who have PCs listening
out for WSPR transmissions. We are talking of ranges across the Atlantic and beyond.
SPOT and/or Iridium sateelite based comms and tracking has always been the serious contenders.
In fact, I think it was I who first relayed my friend Klaus's suggestion of SPOT to this forum.
It seems that a SPOT messenger could be purchased for 100 GBP, plus air time of 100 GBP,
and used after a suitable minor addition of an electronic timer closing contacts on a button.
(I'd love to hear more specific detail on any low cost SPOT solution).
My problem is that even SPOT, at maybe 200 GBP, is the majority of cost (excluding my time),
for any simple, low cost, robot boat solution. Reaching into my pocket to spend more money deters
my putting solutions together early enough for them to be properly tested.
I have the suspicion that others among the Microtransat teams may share the same problems.
How else can we explain that after what must be over 5 years of talking about Microtransat,
and numerous international meetings - some near the sea side - there has only been one attempt ?
i.e. the heroic voyage of Pintar last September.
I cannot believe it is "fear of failure". Pintar failed to cross the Atlantic, but can be admired
as being the first to try, and I'm sure a lot was learned from it. e.g. both SPOT and Iridium failed
- but of course, we don't know why - including maybe Pintar was swallowed by a whale
My approach is to make sure I always have a "toy" to play with. This year that toy has been Snoopy Sloop 5 - the star of the "Snoopy Sails!" video on
www.gpss.co.uk/autop.htm - but he has given lots
of useful data, and continues to do so. e.g. that spoken distance and direction to the next waypoint, and the PICAXE servo controller, is the basis of my much cheaper autopilot solution.
But more about that in a few days time.
There is no point in making a suitable boat and guidance system if we cannot afford to track it
Low cost remote tracking of a small, low costboat is now my priority concern,
even if - in my view - it was always the only essential for Microtransat.
Robin
www.gpss.co.uk