Foiling - the Future or a Folly [Archive]

Guest625101138

02-02-2009, 05:46 PM

There is growing interest in foils.

Probably a mix of drivers:
High speed for low power and low forces
Cost/future of hydrocarbon fuel
Growing awareness that gas guzzling boats are anti-social
Availability of low weight high stiffness materials and knowledge in their application
Health benefits of self powered craft or actively sailed craft
Electric powered craft that perform well
Solar energy craft that perform well

All these factors contribute to the interest. There certainly is a wow factor when a boat flies.

There are many practical hurdles that need to be met but I see a lot of momentum and expect to see wider acceptance of foils on all sorts of pleasure craft.

Rick W

Paul B

02-02-2009, 05:57 PM

I doubt it will become the dominant, mainstream method of sailing. It adds complication, and simplicty sells. Simplicate and add more lightness.

I thought it was interesting to see the designer of the Mirabaud interviewed on The Daily Sail. He indicated that in his opinion it would be very difficult to make a foiler work any larger than what he had there. In fact, it sounded like he might have been thinking of downsizing and trying again at the two hander size.

I'm sure many will tinker, and some classes will emerge. So far I'm not seeing any of it where I am, at the largest dinghy sailing club in SoCal.

Also, I have not seen any movement on the DSS front even since their media blitz mid last year.

What I would like to see is the foilers go off and do their thing, and leave the existing fleets alone. Seems that's what has happened in the FF fleet.

I'm sure someone who has sailed in a class for 20+ years, owned 5 or 6 boats during that time, acted as class President, Secretary, Chief Measurer, etc, and has worked diligently to keep the class vibrant over the years would not be very happy if his class suddenly went foiler and he was driven out. Even if he was replaced by 2 foilers for a net increase in the fleet I don't think this is right. Let the foilers start and nurture their own classes.

robherc

02-02-2009, 08:49 PM

Paul B

02-02-2009, 09:20 PM

I guess I'd have to say that foiling is a "medium-large" branch on the tree of sailing evolution.

Medium-large?

If you had every non-moth foiler that is currently foiling worldwide and put them all on one regatta it wouldn't make a decent sized club Opti fleet.

Take out the Moths and you would have a small handful of boats. Some people here continually mention foilers that have not sailed in ages, or have been given up on, in their list of "current" foilers (I14, 18 footer that has been abandoned, M4, etc).

After the Moths I suppose you have the RS600FFs. How many are there? Less than 20? Less than 10? How many class regattas have they had?

Other than those two, you pretty much have one off projects, and you can count them on your fingers.

I would say the foilers are currently a small twig. An interesting looking twig, but still nothing more.

Chris Ostlind

02-02-2009, 09:26 PM

No review of your understanding necessary, Bistros. I think your take is pretty well balanced.

Rick, I agree with your point that there is likely a growing interest in foiling. However, I also think that it's a fringe interest that is currently enjoying a lot of the Wow factor from the visual and speed sensations and not from the realities that are attached to foiling craft. Soon enough, the wow fad will wear-off and then things will settle back down.

Like any other market sample study where a new product invades an established buy/use tradition, the foilers will absorb a small section of the fringe of the market's bell curve while they are fresh, stabilize at that point and gradually see market share recede for a variety of factors.

The business aspects of the foiling trade; that being a hyper technology driven component of the sailing industry, will have to push the boundaries ever higher, or the freshness of the technology will soon become passe to the buying public. The further the boundaries of new tech solutions are pushed, the further from the largest component of the marketplace the foilers will move. A sort of self-administered limiting function, if you will. You saw this in the sailboarding and windsurfing segment and you'll likely see it for foilers as well.

Pick just about any sector of an outdoor sport where ultra high-tech products staged a coup against the established traditions. When this happens, you eventually see that after the initial exciting rush and subsequent honeymoon, the market share dwindles. It is at that point that the big consumer interest wanes and the more complex/expensive item is relegated to a hard core cadre of users... essentially this is the original, interested audience.

If the core audience is sufficient, then the product can gain a small, albeit potentially profitable, foothold and possibly survive. There will be a fairly tough shakeout of the firms that don't really have a solid product and/or marketing vision and... life goes on for the rest of the sailing community.

For comparison sake, I give you the U.S. sales figures of various classifications of motorcycles as an example of market trends. I can give you the base reasons as to why this type of change is happening if you like, but will leave it out for now and you can draw your own conclusions.

Here are the gross sales figures for 2008 and a comparison to 2007:

2007 Totals 2008 Totals Unit Change % Change

Dual Sport 36,837 45,250 8,413 +22.8%

Off Road 209,739 146,779 -62,960 -30.0%

Street Bikes 647,633 611,133 -36,500 -5.6%

Scooters 54,255 76,748 22,493 +41.5%

Totals 948,464 879,910 -68,554 -7.2%

Clearly, there is a strong move to more utility and economy of purpose and not to highly specialized machines with big dollar price tags and limited utility. The boating market is very much like this set of numbers above. It is similar in the way that it functions for the "average person" type of end user with enough disposable income to afford a near luxury item such as a boat that costs in the $20,000 realm. You guys can draw your own conclusions.

There's a dramatic shift going on to less complex, less spendy and more overall utility that simply can not be denied. To buck these trends as a manufacturer of any recreational vehicle is to invite disaster.

So, to wrap it all up... Yes, I think that there will always some kind of foiling component in the boating world. I do not, however, see it as anything more than a group of special interest enthusiasts when weighed against the total boating environment.

Guest625101138

02-02-2009, 09:46 PM

There will always be boats with foils, and there will always be boats withOUT foils. I think the "revolution" of foiling has already occurred, many years ago. Now they're more of another design option as far as I'm concerned. Something you can add to a design if you want a boat to be more efficient/faster/fly to impress people. They have their pros & cons, and those must be weighed right along with everything else as you reach the compromise that will be your next boat.

I guess I'd have to say that foiling is a "medium-large" branch on the tree of sailing evolution. I don't forsee it falling off any time soon, but I also don't see it replacing the trunk.

The question was on foiling not exclusively sailing. There are many avenues being explored. Some examples:
http://www.airchair.com/
http://www.foilkayak.com/
http://www.extremekites.com.au/forums/showthread.php?t=2990
http://www.youtube.com/watch?v=g3AV1LJwQus
http://www.youtube.com/watch?v=TRd5qMpEUsg

Some have not got past the curiosity stage but there are efforts to market them and some have developed a lot of interest if not yet sales to match. These things have great pose value and that sells. Look at the impracticality of a sports car but there are still plenty on the market.

Who would have thought adding a sail to a surfboard would make something that people wanted to buy.

My personal objective is to be able to slowly run down a rowing 8 and pull past under pedal power. Only hope is with foils. I guess similar aspirations to Peter Ribe:
http://store.foilkayak.com/clinics/
I have a more efficient propulsion system but still to get foils that work well.

Rick W

robherc

02-02-2009, 09:58 PM

How many people here really think foiling is the future of sailing? A "revolution" as it were.

How many people think foiling is a minor branch on the tree of sailing evolution?

The question was on foiling not exclusively sailing. There are many avenues being explored. Some examples:
http://www.airchair.com/
http://www.foilkayak.com/
http://www.extremekites.com.au/forums/showthread.php?t=2990
http://www.youtube.com/watch?v=g3AV1LJwQus
http://www.youtube.com/watch?v=TRd5qMpEUsg

My personal objective is to be able to slowly run down a rowing 8 and pull past under pedal power. Only hope is with foils. I guess similar aspirations to Peter Ribe:
http://store.foilkayak.com/clinics/
I have a more efficient propulsion system but still to get foils that work well.

I think the ORIGINAL question was directly for sailing, but you're exactly right on every single other point you make. I'd love to see you pass that rowing scull too, PLEASE post a video when you achieve it...I've been throwing the idea of a paddle-wheel human-powered foiler in the back of my mind...kind of an "old-meets-new" crazy idea. If you build yours & are successful, then my wife will have run out of ways to talk me out of it! ;)

Paul B

02-02-2009, 10:01 PM

The question was on foiling not exclusively sailing. There are many avenues being explored.

A few years ago I saw someone riding one of those bounce up and down things in SF bay. If you stopped you would sink, and could not water start. That seemed to be an issue.

If you are going to strap a board to your legs and surf like Laird Hamilton is doing in that viseo you better be Laird Hamilton, or damn near as good. A wipeout on that must be pretty ugly.

To keep up with/overtake an 8 how many watts are you going to have to put out, over what duration? Any ideas?

Guest625101138

02-02-2009, 10:03 PM

Actually I forgot the most commercially successful use of a new foil application:
http://www.hobiecat.com.au/support/kayaks/miragedrive.html
Not used for flight but a very successful application of foils. Do not come close to the efficiency of a propeller but good marketing effort and good reputation has given commercial success.

So these are more novel uses of foils rather than the ones we live with all the time like sails, rudders, keels, wings and propellers.

Rick W

Guest625101138

02-02-2009, 11:06 PM

A few years ago I saw someone riding one of those bounce up and down things in SF bay. If you stopped you would sink, and could not water start. That seemed to be an issue.

If you are going to strap a board to your legs and surf like Laird Hamilton is doing in that viseo you better be Laird Hamilton, or damn near as good. A wipeout on that must be pretty ugly.

To keep up with/overtake an 8 how many watts are you going to have to put out, over what duration? Any ideas?

Mark Drela estimated he was working at 220W at 12kts when they were playing around with a fast cruising version of Decavitator. This was their sustainable level for an hour or so but well above what I can do.

I can build a lighter boat and more efficient propulsion system than he was using but I have a lot of work to do on the foils. In my current displacement boat I can hold 15kph for 600m and this requires 270W in calm conditions.

The eights I see train at about 16kph so I get their attention now but I would love to be able to have them working really hard and leave them in my wake.

If I could get everything right I should be able to fly around 8kts for 150W and push up to maybe 14kts at full tilt for a minute or so. My current top speed is 10kts and I can hold maybe 9kts over 100m.

My current boat design holds the world 24 hour distance record so the drive system is well sorted and very efficient. Just need to get lifting foils to match. With good foils I should easily outpace a Flyak. My power application is much smoother and requires much less control - just spin those pedals. I do not need to try hard to out accelerate paddlers. A 400mm prop turning at about 500rpm gives a lot more bite than a paddle dipping in and out of the water no matter how good the paddler is. This is the basis of the Hobie sales pitch, which get a lot of people taken in.

Since December, I have reduced body mass by 3kg and am continuing to maintain fitness level. My aim is a sustainable 150W and to be able to hold above 200W for 15 minutes or more. I am confident if I get foils working well this will be enough to chase down a rowing 8 in training mode.

Rick W

Doug Lord

02-03-2009, 01:51 AM

You simply cannot understand the significance of foiling in sailing without understanding the bi-foiler revolution that began in 1999. While sailing with foils has a long history going back to before the 50's it wasn't until 1999 that the International Moth and International 14 changed everything. It was during that year that both boats sailed on just two foils for the first time in history. It was soon after that that this new configuration began winning major races in the Moth Class-to the exclusion of every other design type today. Up until a practical two foil boat was developed most sailboats that foiled sailed on three or four foils or more. The new configuration is a natural for most dinghies because of its simplicity: you already have a daggerboard and rudder-now to foil you just add a couple of horizontal foils and an altitude control system and you're ready to go. One of the biggest aspects of drag in foiling is the surface penetration of the foils-the bi-foiler takes that down to two surface penetrations vs the old system of three or four or more. And the foilboard takes it down to one surface penetration with two small foils!
Big improvement. The bi-foiler offers the ability to retract foils simply as is illustrated by the RS600FF and foiling 18's.
But the thing that has got peoples attention is that the little 11' Moth has turned the sailing world upside down speed wise: it has been proven faster than an Australian 18, F18 catamaran, A class catamaran and may soon equal or surpass the Tornado catamaran. Who would have ever believed that a little monohull could be so fast?
And that is only the beginning. Bi-foiler technology IS a revolution-not evolution as can be seen by what has happened with the Moth. But there is much more . The simplicity of the foiling system opens up avenues of development impossible before 1999 like the use of just two foils for "foil assist"
upwind with full flying reserved for off the wind, like the use of foils on keelboats for full flying or foil assist, or multihulls with just two foils.
The technology opens the way for hybrid designs that use very small buoyancy pods to make the boat more stable off the foils and therefore much easier for the average person to learn to sail. Coupled with retracting foils and other design innovations a bi-foiler can be designed today that makes this whole experience much more accessible than the often difficult to learn to sail and launch Moth. Innovation in design will allow a "Peoples Foiler" to emerge in much the same way as Hobie emerged during the early days of beach cats.
This is very early days in this revolution and there is much development being done world wide to tap into the potential of one of the most exciting developments in the last 100 years of sailing! The surface has barely been scratched......

sailor2

02-03-2009, 03:33 AM

But the thing that has got peoples attention is that the little 11' Moth has turned the sailing world upside down speed wise: it has been proven faster than an Australian 18, F18 catamaran, A class catamaran and may soon equal or surpass the Tornado catamaran.
Is there anybody else in this world who believe that has happened except Doug Lord ?
Howcome so many who sail on foil moths don't believe that has happened ?

sailor2

02-03-2009, 03:45 AM

My perhaps obvious dislike of foiling "discussions" has nothing to do with the engineering, technology and application of foiling.
There is a lot of technological advantages for foiling technology on boats that are not sailing boats. The most practical application would perhaps be replacing small planing powerboats with foilers offering much smoother & dryer ride in any kind of seaway, possibly more fuel efficient as well. But is there also market potential for that kind of boats ?
That's the real issue as most people are dot tech geeks, but rather conservative instead.

In order to foiling to work on sailing boats is much more demanding to accheave, and results boats more difficult to sail and/or more expensive to buy. Not going to work on cruising boats needing to carry a lot of weight and be easy to sail.
There is potential for fast dinghys for those who want that kind of boats.

Doug Lord

02-03-2009, 06:56 AM

Is there anybody else in this world who believe that has happened except Doug Lord ?
Howcome so many who sail on foil moths don't believe that has happened ?
===================
Much of this including beating a fleet of A Class cats and F18's is documented on Rohan Veals website and the 18 Scott Babbage's site and others.
www.rohanveal.com
Bladerider "Dash for Cash" : http://www.youtube.com/watch?v=OsGFrwquOc4
------------------
French website-Foilers!-excellent-15,000 visits in December! : http://foils.wordpress.com/

bistros

02-03-2009, 08:15 AM

Is there anybody else in this world who believe that has happened except Doug Lord ?
Howcome so many who sail on foil moths don't believe that has happened ?

Nobody other than Doug believes this. Everyone else understands that consistent performance over time across a spectrum of conditions is more important than isolated incidents in favorable conditions. I'm perfectly willing to concede a foiling Moth is capable of spectacular performance IN THE RIGHT CONDITIONS. I'm also willing to prove that many traditional dinghy designs can win races against a foiling Moth in the right conditions.

There is no point arguing this, save your breath.

bistros

02-03-2009, 10:59 AM

Doug:

I've assumed by revolution you meant a violent upheaval in the status quo, followed by significant change. I was unaware you were using the other definition of revolution - rotating around a fixed point and returning to the exact same origin.

Using this definition, your posts on foiling are certainly a "revolution". My apologies for misunderestimating your meaning.

--
It IS a revolution!, (but not the Che Guevara kind)
Sarah/Jeb 2012 - gotcha, wink, wink!

Paul B

02-03-2009, 11:03 AM

PortTacker

02-03-2009, 02:43 PM

I think develpment will continue, and will also continue to be a minor niche if that. Certain people are drawn to that sort of thing, the vast majority will not be.
Even affordable foiling sailboats that worked well didn't gain market hold (such as the Windrider Rave.) Most people will want more versatility in their boats, not to mention durability for the long haul.
The lessons learned from foiling development might well impact the mainstream, who knows? But foiling itself, I don't see ever becoming "the norm."

ancient kayaker

02-03-2009, 09:38 PM

I think the interest in foiling, within the forum at least, is evident from the fact that Bistro’s thread has attracted 20 replies in less than 24 hours.

While unlikely to become dominant, some kind of breakthrough may come along to take it into the big time. Not sure what that might be, perhaps a new design concept or a popular do-it-yourselfer, the “Mirror Foiler!” It may be a commercially available boat that “anyone” can sail, as Hobie tried to do. The Rave comes close, but both seem too heavy.

Some examples of “extreme sailing” like windsurfers and kite boards are limited by the level of physical ability required. The Moth falls into that category, but it need not be a fundamental characteristic of foiling. WOW factor notwithstanding, IMHO the sailing foiler will not achieve public recognition with the current emphasis on extreme speed.

Two things are sure, foiling won’t take off (ugh) unless someone promotes it, and the naysayers will have no effect on the outcome either way. It looks like fun and I would like to try it. But only if it sails: no stinkpots for me thank you.

robherc

02-04-2009, 12:33 AM

It's very much like looking at a baseball game in which one of the pitchers throws 100 pitches and 85 of them are fastballs. By your reasoning, it would indicate that the other team truly loves a steady diet of fastballs.
Hmmm...I think your analogy would only apply if 23 players on the other team were throwing fastballs right back to him...not a very logical analogy.

AK's comment stands the "holds water test"...if it's generating enough interest in the forum to get this many responses, then it's OBVIOUSLY generating interest in this forum. (FACT, not opinion)
It doesn't matter if the responses are disagreeing, only that there is enough interest there to generate them.

CT 249

02-04-2009, 03:46 AM

Growth in the Moth class since foilers came along......

Aussie Moth nationals

'99/00 nationals; 43 boats (inc 8 overseas entries).
00/01 - not available.
01/02 - 32 entries.
02/03 - 29 entries
03/04- 42 entries (first foiler win).
04/05 - 35 entries
05-06 - 29 entries
08/09 - 41 entries

UK Moth nationals

2000 -17
2001- 20
2002- 19
2003- 18
2004- 32 (foilers start winning around this time)
2005- 24
2006- 11
2007- 20
2008- 29

There's no doubt that the top foilers are performing incredibly well in the right conditions, able to pace or beat top A Class and 49ers etc; they are of course much less amazing in other conditions when the non-foilers just keep on flying along. Of course, it's amazing that an 11 footer manages to keep up with such craft (although of course Formula boards do the same).

Oh, and editorial from the UK Moth class site;

"Now the foiler fleet is causing all kinds of headaches for the organisers. Lacking an official PY rating and with vast differences in performance between sailors and in different conditions, it's impossible to set a fair number. The response has been to rate the fastest known sailor (commodores exchange emails on Si Payne) and set that as the yardstick. This year Grafham is using 690 and Queen Mary has given us our own foiler race (although they'll still have to decide where in the sequence to start us - at the back presumably).

A 49er races to PY747. For fun last weekend I squared up to one leading a race at Grafham. He certainly didn't look like an olympic champion but was sailing well enough. Upwind I just hung on and downwind in the gusts made up some ground. But as soon as the breeze died, my angles were hopeless and his big kite pulled him well away.

It's hard to know what the sentiment is in the UK sailing world. Are foilers seen as magic carpets giving average sailors a huge speed boost? Or are they seen as difficult to sail in which only the very best sailors can be fast? In short if a Moth wins the Grafham Grand Prix, will it be 'well done' or 'doesn't count'?

Those of us who know, realise that very few Mothies can live with a 49er round a crowded race track. Our small sail and restricted tactical options mean we spend too much time below full speed or going in the wrong direction. Scott's recent blog says he matched a competitive 18foot skiff in Sydney harbour round a course. He should know, he sails one. For the rest of us, par with a 49er would be a very real challenge - 690 is for champions only."

Doug Lord

02-04-2009, 06:57 AM

I think the interest in foiling, within the forum at least, is evident from the fact that Bistro’s thread has attracted 20 replies in less than 24 hours.

Two things are sure, foiling won’t take off (ugh) unless someone promotes it, and the naysayers will have no effect on the outcome either way. It looks like fun and I would like to try it. But only if it sails: no stinkpots for me thank you.
========================
Not to mention the 129,000 views of "Foiler Design" and 96,000 views of "Moth on Foils".....
-----------------------------
The Moth Class from Simon Paynes perspective(from Sail-World):
Sail-World--The foiler Moth has received a huge amount of publicity over the past couple of years and is now seen as a future Olympic class. What has brought the class out of the closet and made it an acceptable mainstream choice?

Payne--'The Moth scene is fantastic. Most guys and some girls I know in their 30s and 40s are on a diet trying to get into the Moth class. In itself that’s a good thing, because they’re down at the gym getting fit.

'I think it’s because the boat is like where windsurfing was all those years ago where pulling off a gybe is great fun, people learning new manoeuvres - it’s quite frontier based, and people are learning to sail them and having just as much fun darting around as they are sailing races.

'The Moth scene in the UK is not very active right now because it’s about minus six degrees, but it’s growing. My home club Hayling Island has got fourteen moths there now. We don’t have the depth of some of the Olympic sailors like Nathan and Charlie McKee in the US who are coming into the class quite yet, but that’s because team GBR is a pretty intense place to be right now.

'Nathan Outteridge is a professional sailor, and you can see how good he is out there. It’s wonderful for the Moth class to have people like Nathan coming into it. It’s a privilege for people like me to race against him. He’s a class act, and he’ll go far.

Five years ago the Moth class was full of people with beards tinkering in the garage and making stuff in the kitchen, and look at it now. It just makes you feel great that we’re one of the premier dinghy classes at the moment.'

bistros

02-04-2009, 11:30 AM

========================
Not to mention the 129,000 views of "Foiler Design" and 96,000 views of "Moth on Foils".....

Doug, give yourself some credit. You are the single most effective attention getter for foiling threads. Not the technology. Not the boats. Not the other people actually building and sailing foilers. You.

You are 20% archivist, 20% agitator and 60% colossal chain reaction car crash.

People are attracted to your threads because you have taken the Jerry Springer path to success - and you have succeeded wildly. It is hard to resist peeking in to a Doug Lord thread. It is even more difficult to avoid disputing the wild claims and hype presented as fact. I've had you on "Ignore all posts by Doug Lord" for a year on Sailing Anarchy and I still can't resist looking in once in a while. Funny, but I don't bother with Springer or slowing down for car crashes.

I hope this doesn't come as a surprise to you. If it does come as a surprise, I hope it is not shocking. You may have thought all along you are the Tim Russert / "Meet The Press" of foiling. There is a reason why an Australian Moth sailor paid to have "See no Doug, Hear no Doug, Speak no Doug" incorporated as a graphic on his mainsail.

I can't dispute the fact you have attracted enormous attention, but I question if the attention gained actually has been of net benefit to the people who actually design, build and sail (full sized) foilers. Personally, I think you've turned more people off foiling than you've attracted, but that is just my opinion.

I'm not trying to attack you personally here. I hope that you read this, take it for what it is intended and then choose your path forward. If you choose to continue your current method, fine.

Cheers. I wish I lived in Florida and could be sailing instead of typing this in -20. Perhaps you could go sailing today for me.

--
Bill

ancient kayaker

02-04-2009, 12:42 PM

CT: I can see how foilers are causing mixed-class race organisers to have conniptions; I suspect whatever handicapping system they use the outcome is determined by the weather on the day.

It seems to me that the Moth is designed for maximum speed under certain conditions (sufficient wind to foil) and would be handicapped by underwater drag and a hull shape that doesn't look like it would plane. I haven't seen one except in videos and they don't show what they are like when they are

"slogging along through the water
like a proper boat orter"

-so I 'm guessing. It prompts me to wonder if a compromise design would have better all-round weather performance in "open" races; use of Vee foils would reduce on-foil speed with more bits piercing the surface but could be partially raised to function as Bruce foils in light airs allowing more sail to be carried. Make a better all-round boat perhaps, but might need a bigger boat than a Moth.

Doug: rejoice, all your hard work is getting recognition!

Guest625101138

02-04-2009, 06:38 PM

...
Because this is an anonymous forum, folks who might never make a peep in their personal lives feel that they can jump-in and finally feel the power of their opinions without being held directly and personally responsible. They don't have to suffer the scorn of their neighbors or coworkers. They get to simply walk away once they drop their take and sit back and watch the carnival. So, now, they get to have their say on a what looks to be a trendy topic.

.... ;-)

I often wonder why this forum attracts so many wankers unwilling to use their given name. You have to wonder about people's intentions when they are unwilling to identify themselves. You could come up with justifiable reasons if the subject matter was different but this forum does not stray too far from technical matters and the forces shaping development.

Other technical forums I monitor or participate in regularly, have participants using given names. Maybe boating just attracts a weird crowd with something to hide.

Rick W

Doug Lord

02-04-2009, 07:08 PM

Doug: rejoice, all your hard work is getting recognition!
----------------------
Hah! Maybe the old axiom:"any publicity is good publicity" is true?! Sure hope so-I think. But seriously, I think the chance of a "Peoples Foiler" (or three)coming along is almost certain. Many people are working on boats that could do the trick. And Greg Ketterman is being awfully secretive these days! And then there is Dr. Sams Osprey... And I've heard a new aeroSKIFF is making progress-midship wand/manual altitude control and all.....
Its an exciting time for people who think outside the box into which everything before today fits. The technology has not even been applied in 1 % of the potential areas where it can improve sailing for everyone.
For the visionless ,I'm sorry for you-but stay tuned: it's gona get real exciting!!

ancient kayaker

02-04-2009, 11:23 PM

Chris, leaving aside your opinions of Doug for a while if we can, what do you think about the future of foiling? Passing fad, wave of the future, or just an obsession of obscure enthusiasts? I would like to read about Sam Schneider's work, since he seems to be doing what I may decide to do, so can you give us the link please?

Rick, my name is Terry Haines. How do you do. I took the label above because when I first found this forum many of the people posting, except the well known professionals, were using nom de plumes. Over 50% in fact. it seemed amusing so I did the same. In my case it's a descriptive label, what I am rather than who I am. As a nobody in the field of boating, it is more informative than giving my name. It seems to bother Chris from time to time, although he has my name and e-mail. Since I value the opinions of both of you I will be happy to change it. Do you know how I can do that?

PortTacker

02-04-2009, 11:37 PM

This is pretty cool looking, Nigel Irons design:
http://www.nigelirens.com/FRAMEperform.htm

-from just another anonymous wanker

Guest625101138

02-04-2009, 11:40 PM

Terry
I have learnt to value all opinions. I do get frustrated with some from time to time and am prone to offer an opposing opinion sometimes just to start a debate.

Personally I think all the silly names degrades the appeal of the site but that is my opinion.

I do not know how you can change name and carry over all the details of your current user name. I expect it would require some effort for Jeff the moderator. One thing is to add your name as a standard signature. Another is to make your name the Custom User Title in your profile.

Rick W

robherc

02-05-2009, 01:28 AM

Guest625101138

02-05-2009, 01:31 AM

If you were contemplating a useful application for a peoples' foiler I doubt that it would be powered by sails. Wind is simply too fickle. The best time on the water is when it is balmy and calm.

Foiling for sustained periods is beyond the power/weight level of most people so it will not be human powered.

You need about 500W to get impressive speeds with a single person foiler - say up around 20kts. This sort of power level is readily available from model plane parts that cost peanuts.

The main benefit is that you can make a relatively short craft that is easy to transport as a cartopper. It would be no bigger than a mid range sit-on. Make the cockpit fully faired, sitting low with little windage. With a USD100 li-ion battery you would get close to an hour of operation. Say reliable distance covered of 15nm. Easy to double the batteries to go twice as far.

The hull would be set up to be self-righting with the motor pod acting as a ballasted keel. The foils required to lift 100kg at say 15kts would be tiny. Aim to operate a foot or so above water level so small chop is no bother.

I wonder if it would have wide appeal.

Rick W

Guest625101138

02-05-2009, 01:43 AM

Well, Rick;

I hope my nom de plume hasn't bothered you too much, but it's actually been my internet name since, well, since we were all using WFW (Windows for Workgroups) 3.11 and all filenames had to be 7.3 characters. I've used it on several other tech. forums that I participate(d) in, and even own robherc.com (though I haven't updated it in about 7 years).

Anywise, out of my shell, I'll put my "real" name out there for you all:
Rob Hercules (oh wait...Rob+Herc...I get it now!)...sorry, couldn't resist the sarcasm on that one. ;)

And no, I don't mean you any offense Rick....and I understand that it IS irritating to read outlandish posts from some (person), and look to see who it was...another name-hider. Gotcha ;)

Rob
I thought your sirname was Herc - so there you go.

I would certainly be less inclined to call real people wankers. But silly names beg the title. It is like we are in some sort of covert operation where some dare not use their real name - maybe worried the wife might find out how they spend their time.

Rick W

robherc

02-05-2009, 01:49 AM

The main benefit is that you can make a relatively short craft that is easy to transport as a cartopper. It would be no bigger than a mid range sit-on. Make the cockpit fully faired, sitting low with little windage. With a USD100 li-ion battery you would get close to an hour of operation. Say reliable distance covered of 15nm. Easy to double the batteries to go twice as far.

The hull would be set up to be self-righting with the motor pod acting as a ballasted keel. The foils required to lift 100kg at say 15kts would be tiny. Aim to operate a foot or so above water level so small chop is no bother.

I wonder if it would have wide appeal.

Rick W

I don't remember what experimenter's site I saw it on, but someone developed a elec-powered foiler that could "fly" at about 5-10 knots & "supposedly" was going to market it, but I haven't heard any more about it since. Just a snippet.

Chris Ostlind

02-05-2009, 09:45 AM

If you were contemplating a useful application for a peoples' foiler...

Foiling for sustained periods is beyond the power/weight level of most people so it will not be human powered.

... The main benefit is that you can make a relatively short craft that is easy to transport as a cartopper. It would be no bigger than a mid range sit-on. Make the cockpit fully faired, sitting low with little windage. With a USD100 li-ion battery you would get close to an hour of operation. Say reliable distance covered of 15nm. Easy to double the batteries to go twice as far.

I wonder if it would have wide appeal.

I have a feeling, Rick, that it would be worth pursuing, especially in a global market that is growing more and more aware of electric vehicles every day.

It would be sure to spawn a whole pile of backyard electric/mechanical dudes into producing their own take on the concept.

Have a look at this guy's take: http://www.youtube.com/watch?v=ovHAyKpHViU

This guy's: http://www.youtube.com/watch?v=TViDOm9HQsw&feature=related

A Bayliner from an ex-Boeing dude: http://www.youtube.com/watch?v=w54-OEWulDE&feature=related no midship wand, however.

And especially this guy, if you can digest the disco music:
http://www.youtube.com/watch?v=wObflyTPLvM&feature=related

That should spark a few comments

bistros

02-05-2009, 11:47 AM

You need about 500W to get impressive speeds with a single person foiler - say up around 20kts. This sort of power level is readily available from model plane parts that cost peanuts.

The main benefit is that you can make a relatively short craft that is easy to transport as a cartopper. It would be no bigger than a mid range sit-on. Make the cockpit fully faired, sitting low with little windage. With a USD100 li-ion battery you would get close to an hour of operation. Say reliable distance covered of 15nm. Easy to double the batteries to go twice as far.

The hull would be set up to be self-righting with the motor pod acting as a ballasted keel. The foils required to lift 100kg at say 15kts would be tiny. Aim to operate a foot or so above water level so small chop is no bother.

I'd consider buying/building one - it's a drag sitting on shore here on no-wind days, and skiff sailing in under 3 knots of wind is too much like work and uncomfortable (gimme my trapeze harness!). Ottawa is basically a low (read as no!) wind venue all too frequently.

I wonder about the battery costs quoted - I've had to buy replacement laptop lithium-ion cells and I wish I only had to pay $100. How many amp/hours are we talking here?

Would the model airplane parts be able to handle the high drag, slow revolutions and load? I would expect the service target loads and torque requirements to be very different.

In regards to your pen name issues, I've been using bistros since the mid 70's before attending University of Waterloo - it is a 7 letter concatenation of my first and last names (not any made-up pseudo-cover). I was on DARPA-net using this before there was an Internet. It worked with Unix servers at university, DARPA-net and Compuserve naming conventions.

"Handles" on the Internet have a long, respected and well-established history. A handle become a unique, valued identity over time that is less confusing than the 206 people found under "R Willoughby" in just the US (Intelius search). Names are just as easily made up on line as a handle, and if you think using a name when posting provides more credibility about a poster, you are sadly mistaken. There were three or four people on Sailing Anarchy posting as "Doug Lord" this past year - doing so to annoy the "real" one.

It takes all of 0.6 seconds on the Internet to find anything you want on anybody. Seriously, if anyone thinks they can hide behind a handle they understand less about the "Internets" than politicians.

--
Bill

bistros

02-05-2009, 12:58 PM

My God, Bill

Next, you're going to tell me that I'm being watched with Giga res IR and that I have a specific IR signature as registered with NSA. I'm in enough trouble with my wife as it is when I'm up too early doing boat plan sheets.

hmmmm.... maybe it's that chip at the base of my skull I got the last time I was abducted by aliens...? Are they on the Net too?

Help Mr. Wizard!!!!!!!!

Domestic and international Internet traffic in the United States is being scanned constantly - looking for keywords, phrases, use of particular language encoding and particular packet sequences. The National Security Agency's various surveillance programs, implemented at key routing transfer points and ISP gateways are well documented.

This was implemented under the Patriot Act, and continues to run today.

I'm in the communication security business.

Can't comment on the chip in your neck, although I had one installed in my puppy by her vet.

Lots of nasty aliens on the 'net according to Lou Dobbs, the Director of Xenophobia who holds court nightly on the Department of Propaganda Channel (whoops, I mean CNN).

--
Bill

robherc

02-05-2009, 02:23 PM

Next, you're going to tell me that I'm being watched with Giga res IR and that I have a specific IR signature as registered with NSA.....
Let's see...
Chris Ostlind, born & raised in So. Cal.
Doesn't finish most of his plans that are available on Duckworks...
...that's from the very first link that came up on Google...if You'd like to pay about $20USD, I could show you your history of physical addresses, full police traffic/criminal record, known aliases, known acquaintances & family members, plus whom you bought your last 3 houses from/sold them too & who some of your neighbors are/were.
The info IS out there, and it IS publicly easily available...and most of it can be had for free, if one is willing to put in the effort to find it.

Chris Ostlind

02-05-2009, 03:26 PM

Thanks for the intro, Rob. The gesture is most kind.

Here's what the designer page on Duckworks says in total:

Lunada Design/Chris Ostlind

Chris Ostlind grew up in Southern California where he learned to surf (of course) and later to sail and paddle about every kind of boat known. He built quite a few too.

After a long career as an architectural photographer, and a video cameraman/director, Chris is now devoting his time to designing beautiful and functional watercraft for amateur builders.

Chris has long been a contributor to Duckworks Magazine and we are delighted to be able to offer plans for his wonderful designs here.

Note: Several of Chris Ostlind's designs are not totally complete. Most have enough done that you can begin construction and Chris will make every effort to get updates to you in a timely fashion. To find out more about the status of any of these plans, write to chris@wedgesail.com - you can also write to Chris to request printed offsets when you do order plans. Otherwise you will receive those as PDF files.

At this point, 11 of the designs I have done are completed as plan sets. There are 31 more to go and they are all on a schedule... one at a time. Custom design jobs keep falling into the hopper that push back the schedule of stock plan set completions. I'm currently putting the final touches on a Euro version of the Gato Especial, station drawings for the Neo beach cruising cat, an interesting 17' coastal cruising tri and a kid's training skiff called, the Cabrillo.

It's been an interesting journey.

robherc

02-05-2009, 03:31 PM

Chris:
...I meant no disrespect about the designs...just pointing out haw quick/easy it is to find info on pretty much anyone. Personally, I think it's great that you make your designs available through duckworks.
Heck, for many amateurs, partially-finished designs might fit the bill better anywise...easier to imagine your own modifications that way ;)

Guest625101138

02-05-2009, 03:41 PM

Chris
I have seen all of these and I envisage lighter and lower power. The foils would be higher aspect and somewhat more prone I guess than the ones shown. That becomes a challenge for some method of protection.

Maybe we set a challenge for a 750Wh class. The competition is the longest distance travelled in 1 hour.

Bill
I gave up handles once more than 8 characters were used in file names etc. My email name is still a concatenation but most large companies now use first and second name separated by a ".". I have enough clutter in my life that I now force myself to discard things that are obsolete. My strong personal preference is to address a person rather than a handle.

Identity theft is a growing problem I believe but having a handle is not going to alter that as you and Rob point out.

Also on the batteries I did the mental arithmetic too quickly. You would need four of these:
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=8586&Product_Name=ZIPPY_Flightmax_5000mAh_6S1P_25C_
So will set you back USD400 for something over 400Wh. Not sure how long they would last and associated water risks.

There are some here that might be more durable:
http://www.batteryspace.com/index.asp?PageAction=VIEWCATS&Category=1087

Rick W

ancient kayaker

02-05-2009, 09:13 PM

Rick: are you planning to pursue a human powered foiler? Thought I saw something about that someplace but forgot where. For me a foiler would have to be a sailer: no power of any kind or anything remotely smacking of effort, peculiar attachment to paddling notwithstanding.

Perhaps it's the intellectual satisfaction of teasing a bit of use from something that wants to be someplace else as soon as possible. Or maybe I acquired a taste for futility from many years of trying to sell high-tech toys.

Boston

02-05-2009, 09:49 PM

I wonder if it would have wide appeal.

got my interest and the flickers were cool

I wonder what could be done with say five horse power and a two man crew
could it fly?

Best
B

Guest625101138

02-05-2009, 11:07 PM

Rick: are you planning to pursue a human powered foiler? ....

I have done some testing with lifting foils. I think I pointed out elsewhere that I have actually flown under pedal power but that was with 90% of the boat supported on submerged buoyancy so does not really count.

I have a 2.4m wide foil that I can attach to boats but I have only managed to get some lift uncontrollable roll so far.

My new pedal boat will be very light and I might try flying with it. I would like to have swing down foils that can be engaged for high speed operation for short periods.

From what I have experienced in typical sailing conditions you need to find the right time and place to foil. Most of the time my current pedal boat will outpace any sailing boat under 14ft around a triangular course. There might be some days when they have the right window. Lighter winds or stronger winds I go better. I think a sailing foiler will have even smaller operating window.

I actually tried to find the average speed for moths around a course to see how they compare over a range of conditions but have not found anything.

Most people who try my pedal boat are staggered by the ease that they can cover the ground. I can hold a sustained jog on flat ground of 11kph and that is the same speed I can hold on the water in calm weather. Any speed under 11kph is easier physically for me on the water than jogging or walking on land.

Last weekend I covered 29km on the Yarra River in about 3.5hours and that included taking photos at the on-water boat show and numerous photos on the return trip. You would never do this on a sailing foiler.

Very few people have actually experienced the thrill of a fast pedal boat. I may be a tragic but it is the best fun I have ever had on water. It is not something I get bored with. Being able to get above 20kph for bursts would add a new dimension.

Rick W

Guest625101138

02-06-2009, 12:07 AM

got my interest and the flickers were cool

I wonder what could be done with say five horse power and a two man crew
could it fly?

Best
B

If you work hard on the design to get best lift to drag for the desired speed you could expect L/D of 30.

So lets say you can build it to weigh 200kg. The drag will be 70N near enough.

To do 15m/s (say 30kts) the power will be just over 1kW for water drag. Windage would be significant at this speed even with a nicely faired hull and sitting low. So more like 1.5kW allowing for wind. With a good prop you need 2kW at the motor. So 3HP should keep you there.

Getting to that speed is a different matter because the foils need to be optimised for the design speed. You would need to be able to get the hull through the displacement mode at something like 20kts and that is going to take more than 3HP. 5HP might just be enough if the hull is long enough.

Other ideas used for this conundrum is two sets of foils; one for the low speed mode and the other for high speed. Ladder foils also do this. Either option adds weight and complexity.

A feature of the electric motors is that they have tremendous overload capability. This one weighs 1.5kg and peaks at 8.5HP:
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=5142&Product_Name=HXT_80-100-B_130Kv_Brushless_Outrunner_(eq:_70-55)
These are ideal for a foiler because they have the peak rating for take-off and their continuous rating will be good enough for continuous operation. Their low weight is handy as well.

Rick W

CT 249

02-06-2009, 06:40 AM

I often wonder why this forum attracts so many wankers unwilling to use their given name. You have to wonder about people's intentions when they are unwilling to identify themselves. You could come up with justifiable reasons if the subject matter was different but this forum does not stray too far from technical matters and the forces shaping development.

Other technical forums I monitor or participate in regularly, have participants using given names. Maybe boating just attracts a weird crowd with something to hide.

Rick W

Well, surely some of use a "handle" because that was (and still is) the accepted etiquette on the net and, as Bistros pointed out, it has been for a long while. When in Rome etc.

And in many situations, it seems to be more tasteful to be semi-anonymous if you have to refer to the factors underlying a poster's knowledge and opinions. If you're discussing Peanut 24 class boats, for example, saying "I know how a Peanut 24 handles in strong winds because I'm the intergalactic champ" seems a lot less like bragging if it's done anonymously, but it still shows that the poster has good reason to claim expertise in the area.

And why use a name in this context? Why is it important? Sometimes it smacks of "look at me, look at me". And it's hard to see that the wanker count is any lower among those who use their full names.

Guest625101138

02-06-2009, 07:31 AM

Well, surely some of use a "handle" because that was (and still is) the accepted etiquette on the net and, as Bistros pointed out, it has been for a long while. When in Rome etc.

And in many situations, it seems to be more tasteful to be semi-anonymous if you have to refer to the factors underlying a poster's knowledge and opinions. If you're discussing Peanut 24 class boats, for example, saying "I know how a Peanut 24 handles in strong winds because I'm the intergalactic champ" seems a lot less like bragging if it's done anonymously, but it still shows that the poster has good reason to claim expertise in the area.

And why use a name in this context? Why is it important? Sometimes it smacks of "look at me, look at me". And it's hard to see that the wanker count is any lower among those who use their full names.

If I was greeted by someone in the street who said "Hi you can call me CT249" I could not help but think what a wanker. Same thing happens on this forum. I have no hesitation in calling some anonymous handle a wanker. It would certainly be different if I was referring to an individual. If you want the respect an individual is accorded how about using given names.

There may have been some justification for 8 letter "handles" 20 years ago but these days it is just nonsense on a technical forum.

I do not value opinions of handles. If you have an opinion you should be prepared to put your name to it. Anything less is just being rude and self indulgent.

Rick W

Boston

02-06-2009, 10:54 AM

seems like in an era were identity theft and ciber crime are so rampant it is prudent to maintain some level of anonymity

to each his own
B

ancient kayaker

02-06-2009, 11:39 AM

Rick: you’re dead on about the remarkable efficiency of small boats. Somewhat less ambitiously I found that I can comfortably match a brisk walking speed for hours even at my age and condition when I took up paddling, and I find that my range is comparable in either mode.

Boston: I would imagine 5 horses would be adequate for flying. I think Rick’s numbers are correct but I followed a different route. The Flyak site http://www.foilkayak.com/faq/theory/ doesn’t give a take-off speed but there’s a chart that shows a power level cross over between the Flyak and a “regular” kayak at 4 m/s or about 8 k for 225 W power, or 1/3 HP. From the chart 3/4 HP should get you a respectable 20 k, with a total weight of 90 kg. So about 3 HP should fly 4x that all-up weight which should accommodate 2 crew and a reasonably durable hull and motor, perhaps some beer. 5 HP should allow a margin so that time and distance to get up on the foils is acceptable. I assumed horses of the fuel-burning persuasion. I was initially less sanguine about electric power but Rick has found interesting motor data, and elsewhere in the forum there’s a thread on super capacitors.

Perhaps there’s a viable market here, although hull design is a challenge and but we must not forget Chris’s warnings about deadhead logs and other debris, though.

RE: the name debate: I think use of a proper name is appropriate for a professional, optional for others. Whatever one’s opinion on this subject, surely we can all agree to disagree and let it go.

CT 249

02-06-2009, 04:12 PM

If I was greeted by someone in the street who said "Hi you can call me CT249" I could not help but think what a wanker. Same thing happens on this forum. I have no hesitation in calling some anonymous handle a wanker. It would certainly be different if I was referring to an individual. If you want the respect an individual is accorded how about using given names.

There may have been some justification for 8 letter "handles" 20 years ago but these days it is just nonsense on a technical forum.

I do not value opinions of handles. If you have an opinion you should be prepared to put your name to it. Anything less is just being rude and self indulgent.

Rick W

Hmmmm. Personally, I'm happy to let people call themselves whatever they want, and reserve the term "wanker" for those who decide that they alone have the god-like power to determine proper etiquette.

Chris Ostlind

02-06-2009, 04:20 PM

RE: the name debate: ...Whatever one’s opinion on this subject, surely we can all agree to disagree and let it go.

Good enough, Terry. I'll join you in that effort. I've been known to be a wanker every once in awhile... happens like that when one has opinions.

;-)

sailor2

02-08-2009, 09:04 AM

Taken from the link mentioned previously in this thread:
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=5142&Product_Name=HXT_80-100-B_130Kv_Brushless_Outrunner_(eq:_70-55)
Its a monster!
The largest motor we have ever had!

Model: HXT80-100-B
Wire Turns: 8
Resistance: 32ohm
Idle Current: 2A
ESC Required: 130A
Input Voltage : max. 48V
Kv : 130 rpm/V
Weight: 1570g
Shaft: 12mm
Voltage Range: 20-48v
Non Load Current: 2.0A
Maximum Power: 6500W
Equivalent: 60-80cc Gas Engine

$149.95
Is this DC motor as I assume ?
If that motor is connected to 48V voltage and no load is there, it draws 2 amps, so Resistance is R=48V / 2A = 24 ohm
If it's loaded up to have 48V & 130 Amps consume 6240Watts of electic power it gives out less since it's not 100% efficient. At that operation point R=48V / 130A = 0.369 ohm
In some load between those 2 examples amps are between 2 and 130 and as a result R is between 24 ohm & 0.369 ohm. With less voltage resistance is even smaller for same amps.

Can someone explain why it claims R to be 32ohm ????
Under what conditions could that possibly be correct ?
What voltage & what current ?
Even with minimum idle current of 2Amps R=32ohms means 64Volts, which is well above allovable operating range.

If it's AC motor, then impedance is larger than resistance, not smaller.

ancient kayaker

02-08-2009, 09:17 AM

It depends what kind of motor it is, at a guess I would say it is a shunt-wound electronically-commutated motor closely related to a servo motor. If that is the case the 32 ohms applies only to the field winding and the rest of the current passes through the armature. The armature winding will be very low resistance. If the armature is rotating within the magnetic field generated by the field winding it acts like a generator and produces back EMF (EMF = volts) opposing the applied EMF. The armature current flowing is produced by whatever EMF remains divided by the armature resistance. When the armature is free running the armature current is reduced to almost zero, hence only 2A all-up current. Apply drag to the motor so it has to produce torque, and the armature speed slows fractionally, reducing back EMF, allowing armature current to increase. Stall it and it will probably melt!

gggGuest

02-08-2009, 09:51 AM

Hmmmm. Personally, I'm happy to let people call themselves whatever they want, and reserve the term "wanker" for those who decide that they alone have the god-like power to determine proper etiquette.

And it takes less than 5 minutes, if you know anything about CT's interests, to identify him on the net. Some folks user names go back some considerable time to when it was, as another poster noted, impossible to have usemames with spaces or more than 8 characters. And its a lot easier to identify CT249 from Google than it might be to identify which of the hundreds of C**** T***** in the world he is...

In my case I choose to stay anonymous on this forum and this one only because, to be frank, the fruitcake index. I have had concerns about some of the particpants in a way that I don't on, for instance, Sailing Anarchy.

Guest625101138

02-08-2009, 03:35 PM

Taken from the link mentioned previously in this thread:

Is this DC motor as I assume ?
If that motor is connected to 48V voltage and no load is there, it draws 2 amps, so Resistance is R=48V / 2A = 24 ohm
If it's loaded up to have 48V & 130 Amps consume 6240Watts of electic power it gives out less since it's not 100% efficient. At that operation point R=48V / 130A = 0.369 ohm
In some load between those 2 examples amps are between 2 and 130 and as a result R is between 24 ohm & 0.369 ohm. With less voltage resistance is even smaller for same amps.

Can someone explain why it claims R to be 32ohm ????
Under what conditions could that possibly be correct ?
What voltage & what current ?
Even with minimum idle current of 2Amps R=32ohms means 64Volts, which is well above allovable operating range.

If it's AC motor, then impedance is larger than resistance, not smaller.

It is a 3-phase AC motor. You need an ESC to run it. One like this:
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=4691&Product_Name=TURNIGY_Sentilon100A_HV_5-12S_BESC_(Ver4)

The winding resistance is a misprint. It should be 32mohm.

Rick W

sailor2

02-08-2009, 04:13 PM

It is a 3-phase AC motor. You need an ESC to run it. One like this:
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=4691&Product_Name=TURNIGY_Sentilon100A_HV_5-12S_BESC_(Ver4)

The winding resistance is a misprint. It should be 32mohm.
Rick W
Thanks, makes a lot more sense now.
Is ESC (electronic speed controller ?) then just same as variable frequency DC/AC converter or is there more into it. Suppose there must be as the motor was speced like the revs being proportional to voltage, so frequency must also be. Or am I completely off here ?
I'm certainly not upto date about these things anymore, just what they used to be something like 12 years ago. Can similar ESC be used on any other 3-phase AC motor as well and with what voltage range ? Are there something for normal household voltage (230/380V in europe) range with similar cost that allows for using higher frequencys than with direct connection (50hz) ? Would be very useful with my vacuum pump for lamination work.

Guest625101138

02-08-2009, 04:32 PM

Thanks, makes a lot more sense now.
Is ESC (electronic speed controller ?) then just same as variable frequency DC/AC converter or is there more into it. Suppose there must be as the motor was speced like the revs being proportional to voltage, so frequency must also be. Or am I completely off here ?
I'm certainly not upto date about these things anymore, just what they used to be something like 12 years ago. Can similar ESC be used on any other 3-phase AC motor as well and with what voltage range ? Are there something for normal household voltage (230/380V in europe) range with similar cost that allows for using higher frequencys than with direct connection (50hz) ? Would be very useful with my vacuum pump for lamination work.

These are variable frequency. They are referred to as sensorless type. The motors are actually synchronous because they use magnets for excitation. Hence speed is locked to frequency although they also use voltage chopping to get the variable voltage. The speed control is not very precise but it is fine for a boat or plane type application. You also pay a bit more for reversing controller if you want that.

I have not tried an ESC on a normal induction motor but I expect it would work if you could get suitable voltage. These sort of controllers are being used in industry but they cost a lot more. I am not up with the electronics these days but I have a feeling that the power MOSFETS used on the LV stuff get expensive for higher voltage.

I have a couple of Mars motor with controllers. These motors are quite large by comparison with the HXT. The ones I have is continuous rated at 4.5kW on 48V and peak at 9kW. I made a test outboard using one. I just ran off two little 12V batterues that llimited power to around 270W but I was pleased with the result:
http://www.boatdesign.net/forums/attachments/boat-design/20726d1209288392-electric-boat-data-drive_leg_test1.wmv
The Kelly controller I have gives very accurate speed control because the Mars motors have flux sensors but it is really complications that are not needed for a boat motor. One nice feature is that it is switch reversible and, in fact, the controller is full 4-quadrant so I can use for generating as well. This means the same type of motor and controller can be used for a wind generator.

Rick W

robherc

02-08-2009, 05:37 PM

One nice feature is that it is switch reversible and, in fact, the controller is full 4-quadrant so I can use for generating as well. This means the same type of motor and controller can be used for a wind generator.
Hey Rick,

Can you link me to a site where I can price/compare those motors & controllers for my wind-power app. plz? I've been having a hard time finding a suitable motor/generator for my 5KW (7.5KW Max) turbine.

Guest625101138

02-08-2009, 05:55 PM

Rob
This is the place I got mine from:
http://www.kellycontroller.com/

Using the Mars motor as a generator is potentially a compromise because the motor/generator has magnetic cogging. It means it will have trouble self-starting in light wind.

I intended to make a generator with about a 3m blade with the motor/generator connected through a 1:1 right angle drive. It would mean I would not use the unit in its best operating range but I got a good deal on buying both together and it means my generator would be a back up to motor if I wanted.

At this stage I have not even tested the Mars motor in regenerative mode but they are widely used on bikes with this function.

Rick W

robherc

02-08-2009, 06:01 PM

I don't think I even remember what "light wind" is since I've been living here in El Paso for so long...if we go a week without the wind speed topping 30mph, somebody must've stolen the weathervane...because that just DOESN'T happen here (I live almost within throwing distance of a ridge of 1500ft "mountains"...and my house is at almost 4000' elevation). ;)
I'll probably try to install some form of CVT for it though, if I have any problems.

Guest625101138

02-08-2009, 06:22 PM

Rob
The limits that you need to work within for the PMDC Mars motor are 100A rated current and 70rpm per volt.

If you want to get 5kW from it with the 100A limit you need to produce 50V. That means spinning it at 3500rpm. If you are using an open bladed turbine it will be spinning much slower than this so you will need to gear up. This will make the cogging even more pronounced. You may need some smarts in the system to automatically motor it if the wind drops and then kicks back up.

I have not gone into a lot of detail on the Kelly controller other than using it as a motor controller. It is intended for vehicle use so the regen function is used like a brake with separate control input. From memory the level of braking is adjustable so you need smarts to optimise power output at any given wind speed.

There is a larger Mars motor but it has brushes and I wanted to avoid these.

I am impressed with the motor and controller. The connection diagram provided was wrong but once past this it all worked well. The motors are quite impressive. I can see why they get a lot of positive comment.

Rick W