Robatoy wrote:

WTF ARE those things?

In polite society, they are known as "STINK ****S".

Take your choice, jet skis, motorcycles, power boats, snowmobiles,
etc.

They all are loud and they all stink.

Lew

Lew

"Morris Dovey" wrote

Propulsion will be essentially a straight path with a tee connection to
the engine between a pair of check valves. During the expansion half of
the cycle water will be discharged rearward, and during the contraction
half of the cycle water will be sucked in from the forward direction.

I don't need to go fast - I just need to come _back_.

Wasn't it Mr Natural who said that you didn't need to move fast. Just look
cool.

He also said, "Keep on truckin'."

"Lew Hodgett" wrote in message
...

Robatoy wrote:

WTF ARE those things?

In polite society, they are known as "STINK ****S".

Take your choice, jet skis, motorcycles, power boats, snowmobiles, etc.

They all are loud and they all stink.

Lew


I guess it's safe to say you wouldn't like my Harley. It sets off car
alarms.

On 3/12/2010 6:28 PM, Robert Bonomi wrote:
In ,
Morris wrote:

With a platform like the Hobie, I think I can mount a tracking solar
concentrator and have 3-4 kW of input power to work with and (perhaps)
50% of that in pump power.

That'll give you a theoretical roughly 2HP. Enough to move it around,
but -not- with much speed. Think 'trolling motor'.

OTOH, if you can fit one concentrator/fluidyne, maybe you can get 2-3 of
'em on board. Now, you're approaching the capabilities of a 5HP outboard.
That should be enough to leave a wake -- at least a small one.grin

Two is a definite maybe - but from a practical standpoint, just one will
be an accomplishment, and a two-mile round trip on a calm, sunny day
should be enough to stir up a bit of interest. It might even be a good
thing to set a record that'd be easy for someone else to beat.

Heh - it just occurred to me that if I needed a horn, I could disconnect
the pump and use the engine (at say, } to warn off the jet
skiers.

That hurts just to *think* about it.

Here's a video showing a couple of very crude pipe oscillators being
driven with a small propane flame:

http://www.youtube.com/watch?v=_L5fK...eature=channel

It's an application of the gas laws that I'd never thought about, and
some really serious heat (say, about 200 suns on 8' of tube) should
produce a pretty good hoot. :-]

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/

In article ,
Morris Dovey wrote:
On 3/12/2010 6:28 PM, Robert Bonomi wrote:
In ,
Morris wrote:

With a platform like the Hobie, I think I can mount a tracking solar
concentrator and have 3-4 kW of input power to work with and (perhaps)
50% of that in pump power.

That'll give you a theoretical roughly 2HP. Enough to move it around,
but -not- with much speed. Think 'trolling motor'.

OTOH, if you can fit one concentrator/fluidyne, maybe you can get 2-3 of
'em on board. Now, you're approaching the capabilities of a 5HP outboard.
That should be enough to leave a wake -- at least a small one.grin

Two is a definite maybe - but from a practical standpoint, just one will
be an accomplishment, and a two-mile round trip on a calm, sunny day
should be enough to stir up a bit of interest. It might even be a good
thing to set a record that'd be easy for someone else to beat.

Would that be a 'solar-powered boat' record?

How about a _water-powered_ boat record? (*THAT* just might appeal to Guiness!


Or, if you *really* want to stir up interest, you find a way use something like
like carp, or catfish, for thermal mass. Then you lit it slip that the boat
is powered by a "fish/sun reactor" (best said when slurred a little). An
'inherently-safe, non-radioactive' device of your own design. Hang a pole
over the stern, and claim you've 'gone fission'.

If you're going to have fun with the idea, you may as well *REALLY* have fun
with it. GRIN

Heh - it just occurred to me that if I needed a horn, I could disconnect
the pump and use the engine (at say, } to warn off the jet
skiers.

That hurts just to *think* about it.

Here's a video showing a couple of very crude pipe oscillators being
driven with a small propane flame:

http://www.youtube.com/watch?v=_L5fK...eature=channel

It's an application of the gas laws that I'd never thought about, and
some really serious heat (say, about 200 suns on 8' of tube) should
produce a pretty good hoot. :-]

*LONG* time ago, there was a 'traveling science show' that went around to the
high schools. one of the things they brought was a bunch of cardboard tubes
(from mailing-tube size up to a 16' long, circa 8" ID, carpet roller). they
each had a section of metal screening in them a short distance in from one
end. Hold it carefully vertical over a high-output Bunsen burner, and let
the screen heat up, then remove it from the heat source. Fairly shortly
it would start to 'sing' -- louder, and louder, as it found it's "voice".

The carpet roller was -really- impressive; one might say profundo so.

With the rapid and frequent movement of the small Hobie, wouldn't
a solar tracking system be large, complex and take a good deal of
power to operate effectively?
--
Nonny
When we talk to God, we're praying,
but when God talks to us,
we're schizophrenic.
What's the deal?

On 3/12/2010 11:44 PM, Nonny wrote:
With the rapid and frequent movement of the small Hobie, wouldn't a
solar tracking system be large, complex and take a good deal of power to
operate effectively?

Not necessarily. The control portion can be as tiny/simple/inexpensive
as this:

http://www.redrok.com/electron.htm#led3x (warning: large page!)

and small 12 VDC automotive motors with appropriate reduction gearing
driving lead screws should be adequate for positioning. I'd guess that a
marine/deep discharge battery should be enough for the test drive.

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/

On 3/13/2010 12:30 AM, Morris Dovey wrote:
On 3/12/2010 11:44 PM, Nonny wrote:
With the rapid and frequent movement of the small Hobie, wouldn't a
solar tracking system be large, complex and take a good deal of power to
operate effectively?

Not necessarily. The control portion can be as tiny/simple/inexpensive
as this:

http://www.redrok.com/electron.htm#led3x (warning: large page!)

and small 12 VDC automotive motors with appropriate reduction gearing
driving lead screws should be adequate for positioning. I'd guess that a
marine/deep discharge battery should be enough for the test drive.

Oops - I meant to point out (but forgot) that the tracking system's
primary job will be to accommodate the inertia of the collector - to
keep it in the same orientation while the boat moves under it. This
should provide minimal loading on the motors.

Tracking the apparent movement of the sun will, I think, be smallest
part of the job.

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/

On Sat, 13 Mar 2010 01:45:55 -0600, the infamous Morris Dovey
scrawled the following:

On 3/13/2010 12:30 AM, Morris Dovey wrote:
On 3/12/2010 11:44 PM, Nonny wrote:
With the rapid and frequent movement of the small Hobie, wouldn't a
solar tracking system be large, complex and take a good deal of power to
operate effectively?

Not necessarily. The control portion can be as tiny/simple/inexpensive
as this:

http://www.redrok.com/electron.htm#led3x (warning: large page!)

and small 12 VDC automotive motors with appropriate reduction gearing
driving lead screws should be adequate for positioning. I'd guess that a
marine/deep discharge battery should be enough for the test drive.

Oops - I meant to point out (but forgot) that the tracking system's
primary job will be to accommodate the inertia of the collector - to
keep it in the same orientation while the boat moves under it. This
should provide minimal loading on the motors.

Tracking the apparent movement of the sun will, I think, be smallest
part of the job.

How about air-loading some cylinders connected to the collector
system's (weighted) base to allow semi-free pivoting? It would
counteract the rocking motion of the boat to a great extent so
feedback from the position sensors would be diminished, lessening the
collector's "need to adjust" sensing. Are you using some sort of time
delay, too?

--
Perhaps the most valuable result of all education is the ability to
make yourself do the thing you have to do, when it ought to be done,
whether you like it or not; it is the first lesson that ought to be
learned; and however early a man's training begins, it is probably
the last lesson that he learns thoroughly.
-- Thomas H. Huxley

On 3/13/2010 11:06 AM, Larry Jaques wrote:
On Sat, 13 Mar 2010 01:45:55 -0600, the infamous Morris Dovey
scrawled the following:

On 3/13/2010 12:30 AM, Morris Dovey wrote:
On 3/12/2010 11:44 PM, Nonny wrote:
With the rapid and frequent movement of the small Hobie, wouldn't a
solar tracking system be large, complex and take a good deal of power to
operate effectively?

Not necessarily. The control portion can be as tiny/simple/inexpensive
as this:

http://www.redrok.com/electron.htm#led3x (warning: large page!)

and small 12 VDC automotive motors with appropriate reduction gearing
driving lead screws should be adequate for positioning. I'd guess that a
marine/deep discharge battery should be enough for the test drive.

Oops - I meant to point out (but forgot) that the tracking system's
primary job will be to accommodate the inertia of the collector - to
keep it in the same orientation while the boat moves under it. This
should provide minimal loading on the motors.

Tracking the apparent movement of the sun will, I think, be smallest
part of the job.

How about air-loading some cylinders connected to the collector
system's (weighted) base to allow semi-free pivoting? It would
counteract the rocking motion of the boat to a great extent so
feedback from the position sensors would be diminished, lessening the
collector's "need to adjust" sensing.

I like the idea, but am /really/ trying to avoid "scope creep" here.

There's another aspect - I plan on posting photos and videos of whatever
I end up with, and I don't want any of that to be easily adapted for
pickup truck mountable fire control or weapons platforms.

Are you using some sort of time delay, too?

Duane Johnson's (redrok.com) little LED-based controller incorporates an
adjustable delay feature that I suspect will end up being tweaked
immediately before and during the voyage.

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/

On Sat, 13 Mar 2010 12:36:47 -0600, the infamous Morris Dovey
scrawled the following:

On 3/13/2010 11:06 AM, Larry Jaques wrote:
On Sat, 13 Mar 2010 01:45:55 -0600, the infamous Morris Dovey
scrawled the following:

On 3/13/2010 12:30 AM, Morris Dovey wrote:
On 3/12/2010 11:44 PM, Nonny wrote:
With the rapid and frequent movement of the small Hobie, wouldn't a
solar tracking system be large, complex and take a good deal of power to
operate effectively?

Not necessarily. The control portion can be as tiny/simple/inexpensive
as this:

http://www.redrok.com/electron.htm#led3x (warning: large page!)

and small 12 VDC automotive motors with appropriate reduction gearing
driving lead screws should be adequate for positioning. I'd guess that a
marine/deep discharge battery should be enough for the test drive.

Oops - I meant to point out (but forgot) that the tracking system's
primary job will be to accommodate the inertia of the collector - to
keep it in the same orientation while the boat moves under it. This
should provide minimal loading on the motors.

Tracking the apparent movement of the sun will, I think, be smallest
part of the job.

How about air-loading some cylinders connected to the collector
system's (weighted) base to allow semi-free pivoting? It would
counteract the rocking motion of the boat to a great extent so
feedback from the position sensors would be diminished, lessening the
collector's "need to adjust" sensing.

I like the idea, but am /really/ trying to avoid "scope creep" here.

There's another aspect - I plan on posting photos and videos of whatever
I end up with, and I don't want any of that to be easily adapted for
pickup truck mountable fire control or weapons platforms.

No doubt _that_ has already been done six ways from Sunday. Don't
sweat it. People doing that would have lots of money to buy
sophisticated compensation units.


Are you using some sort of time delay, too?

Duane Johnson's (redrok.com) little LED-based controller incorporates an
adjustable delay feature that I suspect will end up being tweaked
immediately before and during the voyage.

Yeah, prolly so.

--
I must study politics and war that my sons may have liberty to study
mathematics and philosophy. My sons ought to study mathematics and
philosophy, geography, natural history, naval architecture, navigation,
commerce, and agriculture, in order to give their children a right to
study painting, poetry, music, architecture, statuary, tapestry, and
porcelain.
-- John Adams

On 3/13/2010 11:28 PM, Larry Jaques wrote:
On Sat, 13 Mar 2010 12:36:47 -0600, the infamous Morris Dovey
scrawled the following:

There's another aspect - I plan on posting photos and videos of whatever
I end up with, and I don't want any of that to be easily adapted for
pickup truck mountable fire control or weapons platforms.

No doubt _that_ has already been done six ways from Sunday. Don't
sweat it. People doing that would have lots of money to buy
sophisticated compensation units.

No doubt - but not by everyone who might like to have, and I'm not
inclined to provide a "how-to" for doing it on the cheap.

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/

On 3/14/2010 9:04 AM, Morris Dovey wrote:
On 3/13/2010 11:28 PM, Larry Jaques wrote:
On Sat, 13 Mar 2010 12:36:47 -0600, the infamous Morris Dovey
scrawled the following:

There's another aspect - I plan on posting photos and videos of whatever
I end up with, and I don't want any of that to be easily adapted for
pickup truck mountable fire control or weapons platforms.

No doubt _that_ has already been done six ways from Sunday. *Don't
sweat it.* People doing that would have lots of money to buy
sophisticated compensation units.

No doubt - but not by everyone who might like to have, and I'm not
inclined to provide a "how-to" for doing it on the cheap.

I'd prefer not to sweat it, but do. By way of explanation let me share a
short thread I saved (OP had a middle-eastern name and was posting via
Google Groups from the UK):

comp.lang.c - 2006 July 20-21
Subject: Center of Contour

start of thread

Speed:

Could you please tell me what is the most efficient way of finding the
center of mass of the area enclosed by a closed contour.

I have a considerable circular region with streaks coming out of it in
either direction. Basically i want to find the center of the circular
region but it is getting offset due to the presence of connected
outlier segments.

I am working with binary images only.

Morris:

It's not really a difficult problem; but the answer would depend on what
you mean by "efficiency". Are you looking for the smallest code
footprint - or are you looking for fastest execution time?

Speed:

I am working with a 120x160 binary edge image and by efficient I mean -
mostlly speed of execution.

Morris:

I thought it might be an interesting exercise. Including some #defines
to parameterize the problem, the solution took fewer than 2 dozen
statements. It was compact _and_ fast.

Pleased with myself, I leaned back and thought about possible/probable
uses for the code...
....and then deleted the files.

Sometimes life just sucks.

End of thread

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/