May I suggest Infra red data transfer
cheap, power miserly and readily available
Rgs
Tony
----- Original Message -----
From: jjtctaylor
To: harryproa@...
Sent: Thursday, January 01, 2004 9:35 AM
Subject: [harryproa] Re: Vane Control


Dave,

The teleflex is a possibility but has similar issues to hard wired electrical
control. There is about + & - 165 degrees of rotation on the boom so the
cables electrical or mechanical have to flex constantly with a significant
amount of slack for the wrap. Boom is limited to 330 degrees due to stays
from the mast top. To minimize the kink probably would have to route the
cable from mast base up to the yoke. Turn the yoke vertical so the ram/
cable can work easiest.

The electrical power is really minor, 99.99% of the time the control circuit
is
idle with only about 100ma draw for communication. A small 12V AGM
battery delivers 15 amp-hours before reaching 40% discharge or at least 6-7
days. The current draw for a DC drive might be 10 amps, but only for 10-20
seconds to adjust the vane. At all other times the gearbox/ worm drive keeps
the vane at the same adjusted angle. Essentially the drive works about as
often as you might shunt or change sail trim each day. Easy for solar to keep
up with that demand.

Thanks for the cable suggestion. I'll look at how much slack that will take
and
how to control the extra cable to prevent kink. Have to rig up a gearbox at
the helm end versus trying to deal with gears at the ram end of the cable.
The cable has limits on extension so makes sense to do it that way.

Regards,

JT
--- In harryproa@..., Dave Howorth <Dave.Howorth@a...>
wrote:
> jjtctaylor wrote:
>
> >Vanes auto adjust the boom for proper wind angle. Control lines
> >from the helm to the vane are impractical cause of the boom
> >movement. Control lines from the helm to the mast and then to
> >the vane also has problems with correcting the precession
> >angle of the boom movement on the vane angle.
> >
> >I have looked around for bluetooth communication to a DC
> >stepper motor drive controller. But that stuff is still in engineering
> >infancy. Lots of robot builders tinkering but no tested and
> >supported products. The marine industry in general has not
> >embraced wireless the connection at all. Looking for alternative
> >ideas to manage vane angle as a single handed sailor. The
> >idea is to control the vane angle wirelessly using a stepper
> >motor & gearbox to a rudder yoke. Power is provided by an AGM
> >12V battery recharged by solar cells. Essentially entirely self
> >contained on the boom. No wires at all.
> >
> >If the boat heading is on autopilot and the vane autoadjusts the
> >boom angle, guess it would be time for lunch. Simple solutions
> >are better, but it needs to be efficient. I can always put the drive
> >controller inside the LW hull and run wires out to the boom, but I
> >know the wires will eventually fail due to boom movement. Self
> >contained seems more elegant.
> >
> >
> If you're going to go wireless, then a strong contender for the
> communications is surely a normal radio remote control, as used on model
> yachts?
>
> I'm impressed if solar cells will provide enough power - I'd guess a
> wired system with slip rings and/or multiple flexible, replaceable
> linkages at the mast-boom joint would be more reliable?
>
> But personally I'd be looking for a mechanical system - could you not
> use a morse/teleflex cable for the tricky part to allow for mast/boom
> movement, and then regular 'string' for the rest?
>
> Cheers, Dave



To unsubscribe from this group, send an email to:
harryproa-unsubscribe@...




Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.


[Non-text portions of this message have been removed]