[Public-List] Public-List Digest, Vol 3477, Issue 1
charles pleisse via Public-List
public-list at lists.alberg30.org
Wed May 31 14:24:02 PDT 2017
It's all just a bunch of voodoo!
On May 31, 2017 3:07 PM, "via Public-List" <public-list at lists.alberg30.org>
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> Today's Topics:
>
> 1. america cup (Jim Mennucci via Public-List)
> 2. Re: america cup (Michael Connolly via Public-List)
> 3. Re: america cup (Mike Meinhold via Public-List)
> 4. Re: america cup (Gordon Laco via Public-List)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Wed, 31 May 2017 10:11:05 -0400
> From: Jim Mennucci via Public-List <public-list at lists.alberg30.org>
> To: Alberg 30 Public List -- open to all
> <public-list at lists.alberg30.org>
> Subject: [Public-List] america cup
> Message-ID:
> <CAKU7ktj=WnzONq5MLj80oKp=JjffSUATu5yv2xoLdtf=07HLaQ@
> mail.gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> Can anyone add to my understanding of how the hydraulically driven
> hydrofoils work on the Americas cup 42 footers now racing in Bemuda--
> here's what I think i'm seeing:
>
> - In a way its kind a cool--going 30+ knots up and down wind doesn't
> require much sail trim...hydrofoil trim is another matter. Talk about
> changing sail boat racing as we all understand it. Trophy goes to team
> that is best at hydrofoil control, in fact hydrofoil control is the only
> area of boat design the is somewhat left to the syndicates to control on
> their own. . Optimizing hydrofoil control maximizes speed.
>
> - unlike the 72 footers, the 40 footers will use hand controls i.e., no
> closed-loop feed-back controls for the hydrofoils--this is what I wonder
> about? The hydraulic directional control valves used to pivot the foils
> use some sort of electrically controlled linear actuator to open and close
> flow to the hydraulic actuators, It would be easy to add some feed back
> control to the electrical part of the valve and if they don't that's good
> because of the additional skill needed to manually maintain stability
>
> - article I read says stored energy (accumulators) are not allowed and the
> hydraulics must be provided by hand pump--hence they're always pumping
> (like maniacs) to have fluid under pressure (must be a relief valve to
> regulate pressure)
>
> - the article talks about 3 hydrofoil controls: Cant, lift and pitch are
> the 3 names used.in the article.
> - It sounds like cant angle corresponds to roll which is used to
> add/control righting moment. Canting the wing off vertical tilts the
> horizontal part of the wing which should result in some loss in lift making
> an adjustment to the angle of attack to rebalance the lift--this is where
> feedback control would be nice but making the helmsmen do the adjustments
> in a manner that maintains foil stability adds old-fashioned skill to the
> mix. Thoughts? pivoting the hydrofoil outboard adds righting moment
> - lift control would pivot the hydrofoil in the pitch plane to
> change angle of attack
> - pitch control to me is the same as lift except its listed as a
> separate function. So I wonder if the dagger board and the rudder foils
> work in concert to change the pitch of the boat--much like bow and stern
> planes on a submarine
> - looks like linear hydraulic actuators are used to control 2 rotational
> degrees of freedom on the dagger board foils and a single actuator to pitch
> the rudder foils.
> - the foil controls are built into the helm wheel and its looks like they
> run the system open circuit i.e., no feedback control. They hit buttons
> built into the helm to open the directional control valves. So the
> helmsmen is also the foil trimmer.
>
> any insight, thoughts appreciated
>
> Jim Mennucci
>
>
> ------------------------------
>
> Message: 2
> Date: Wed, 31 May 2017 14:41:29 +0000 (UTC)
> From: Michael Connolly via Public-List
> <public-list at lists.alberg30.org>
> To: Jim Mennucci <jimmennucci at gmail.com>, Alberg 30 Public List --
> open to all <public-list at lists.alberg30.org>
> Subject: Re: [Public-List] america cup
> Message-ID:
> <2138355342.39056283.1496241689415.JavaMail.zimbra at comcast.net>
> Content-Type: text/plain; charset=utf-8
>
> Jim,
> I haven't had enough coffee this morning to get into
> this.......................will speak up later.
> Michael
>
> ----- Original Message -----
>
> From: "Jim Mennucci via Public-List" <public-list at lists.alberg30.org>
> To: "Alberg 30 Public List -- open to all" <public-list at lists.alberg30.org
> >
> Sent: Wednesday, May 31, 2017 10:11:05 AM
> Subject: [Public-List] america cup
>
> Can anyone add to my understanding of how the hydraulically driven
> hydrofoils work on the Americas cup 42 footers now racing in Bemuda--
> here's what I think i'm seeing:
>
> - In a way its kind a cool--going 30+ knots up and down wind doesn't
> require much sail trim...hydrofoil trim is another matter. Talk about
> changing sail boat racing as we all understand it. Trophy goes to team
> that is best at hydrofoil control, in fact hydrofoil control is the only
> area of boat design the is somewhat left to the syndicates to control on
> their own. . Optimizing hydrofoil control maximizes speed.
>
> - unlike the 72 footers, the 40 footers will use hand controls i.e., no
> closed-loop feed-back controls for the hydrofoils--this is what I wonder
> about? The hydraulic directional control valves used to pivot the foils
> use some sort of electrically controlled linear actuator to open and close
> flow to the hydraulic actuators, It would be easy to add some feed back
> control to the electrical part of the valve and if they don't that's good
> because of the additional skill needed to manually maintain stability
>
> - article I read says stored energy (accumulators) are not allowed and the
> hydraulics must be provided by hand pump--hence they're always pumping
> (like maniacs) to have fluid under pressure (must be a relief valve to
> regulate pressure)
>
> - the article talks about 3 hydrofoil controls: Cant, lift and pitch are
> the 3 names used.in the article.
> - It sounds like cant angle corresponds to roll which is used to
> add/control righting moment. Canting the wing off vertical tilts the
> horizontal part of the wing which should result in some loss in lift making
> an adjustment to the angle of attack to rebalance the lift--this is where
> feedback control would be nice but making the helmsmen do the adjustments
> in a manner that maintains foil stability adds old-fashioned skill to the
> mix. Thoughts? pivoting the hydrofoil outboard adds righting moment
> - lift control would pivot the hydrofoil in the pitch plane to
> change angle of attack
> - pitch control to me is the same as lift except its listed as a
> separate function. So I wonder if the dagger board and the rudder foils
> work in concert to change the pitch of the boat--much like bow and stern
> planes on a submarine
> - looks like linear hydraulic actuators are used to control 2 rotational
> degrees of freedom on the dagger board foils and a single actuator to pitch
> the rudder foils.
> - the foil controls are built into the helm wheel and its looks like they
> run the system open circuit i.e., no feedback control. They hit buttons
> built into the helm to open the directional control valves. So the
> helmsmen is also the foil trimmer.
>
> any insight, thoughts appreciated
>
> Jim Mennucci
> _______________________________________________
> These businesses support your Association:
> http://www.alberg30.org/store/A30supporters.html
> Please support them.
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>
>
>
> ------------------------------
>
> Message: 3
> Date: Wed, 31 May 2017 11:35:40 -0400
> From: Mike Meinhold via Public-List <public-list at lists.alberg30.org>
> To: Jim Mennucci <jimmennucci at gmail.com>, Alberg 30 Public List --
> open to all <public-list at lists.alberg30.org>
> Subject: Re: [Public-List] america cup
> Message-ID:
> <CAOvfohfZoPqSTLbAwp9ZF0Mdo2v6_diTHakXs+nvTJH7hP1FWg at mail.
> gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> Jim
> I agree that it's all about trimming foils, and all the helmsman's
> responsibility - but like so much of the America's Cup - that's
> rule-driven.
>
> Of course the goal of all the foil geometry, position , and potential
> dynamic control is identical to the Alberg 30's keel and rudder - balance
> hydrodynamic lift and drag against aerodynamic lift and drag with minimal
> drag. The foils add a much higher vertical component to lift the boat and
> reduce the drag. As you say, when you no longer are using hydrostatic
> balance, you must get pitch balance from the foils also.
>
> A simpler picture is a pair of horizontal foils that cant with heel, so
> they always lift against gravity, and a a pair of vertical foils that cant
> with heel and leeway, so their lift and drag matches the aerofoiils (sails)
> lift and drag. L-Foils are a compromise to stay within a certain number
> of moving foils. The L-Foils use a single foil to get vertical and
> transverse lift.
>
> The simpler picture allows you to separate the "flying" function from the
> optimal forward-speed function. I think you would ideally have separate
> controls for these two goals.
>
> The AC 42's can't do this, so helm must also fly!
>
> I would like to see these boats in some bigger waves and see how they
> control them!
>
> Mike
>
> On Wed, May 31, 2017 at 10:11 AM, Jim Mennucci via Public-List <
> public-list at lists.alberg30.org> wrote:
>
> > Can anyone add to my understanding of how the hydraulically driven
> > hydrofoils work on the Americas cup 42 footers now racing in Bemuda--
> > here's what I think i'm seeing:
> >
> > - In a way its kind a cool--going 30+ knots up and down wind doesn't
> > require much sail trim...hydrofoil trim is another matter. Talk about
> > changing sail boat racing as we all understand it. Trophy goes to team
> > that is best at hydrofoil control, in fact hydrofoil control is the only
> > area of boat design the is somewhat left to the syndicates to control on
> > their own. . Optimizing hydrofoil control maximizes speed.
> >
> > - unlike the 72 footers, the 40 footers will use hand controls i.e., no
> > closed-loop feed-back controls for the hydrofoils--this is what I wonder
> > about? The hydraulic directional control valves used to pivot the foils
> > use some sort of electrically controlled linear actuator to open and
> close
> > flow to the hydraulic actuators, It would be easy to add some feed back
> > control to the electrical part of the valve and if they don't that's good
> > because of the additional skill needed to manually maintain stability
> >
> > - article I read says stored energy (accumulators) are not allowed and
> the
> > hydraulics must be provided by hand pump--hence they're always pumping
> > (like maniacs) to have fluid under pressure (must be a relief valve to
> > regulate pressure)
> >
> > - the article talks about 3 hydrofoil controls: Cant, lift and pitch are
> > the 3 names used.in the article.
> > - It sounds like cant angle corresponds to roll which is used to
> > add/control righting moment. Canting the wing off vertical tilts the
> > horizontal part of the wing which should result in some loss in lift
> making
> > an adjustment to the angle of attack to rebalance the lift--this is where
> > feedback control would be nice but making the helmsmen do the adjustments
> > in a manner that maintains foil stability adds old-fashioned skill to the
> > mix. Thoughts? pivoting the hydrofoil outboard adds righting moment
> > - lift control would pivot the hydrofoil in the pitch plane to
> > change angle of attack
> > - pitch control to me is the same as lift except its listed as a
> > separate function. So I wonder if the dagger board and the rudder foils
> > work in concert to change the pitch of the boat--much like bow and stern
> > planes on a submarine
> > - looks like linear hydraulic actuators are used to control 2 rotational
> > degrees of freedom on the dagger board foils and a single actuator to
> pitch
> > the rudder foils.
> > - the foil controls are built into the helm wheel and its looks like they
> > run the system open circuit i.e., no feedback control. They hit buttons
> > built into the helm to open the directional control valves. So the
> > helmsmen is also the foil trimmer.
> >
> > any insight, thoughts appreciated
> >
> > Jim Mennucci
> > _______________________________________________
> > These businesses support your Association:
> > http://www.alberg30.org/store/A30supporters.html
> > Please support them.
> > _______________________________________________
> > Public-List mailing list
> > Public-List at lists.alberg30.org
> > http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
> >
>
>
> ------------------------------
>
> Message: 4
> Date: Wed, 31 May 2017 11:36:59 -0400
> From: Gordon Laco via Public-List <public-list at lists.alberg30.org>
> To: Mike Meinhold <meinhold272 at gmail.com>, George Dinwiddie via
> Public-List <public-list at lists.alberg30.org>, Jim Mennucci
> <jimmennucci at gmail.com>
> Subject: Re: [Public-List] america cup
> Message-ID: <E3912900-7B45-4FDC-96B0-7FA2AF59304B at csolve.net>
> Content-Type: text/plain; charset="UTF-8"
>
> America?s Cup has come a long way from yacht racing?
>
> On 2017-05-31, 11:35 AM, "Public-List on behalf of Mike Meinhold via
> Public-List" <public-list-bounces at lists.alberg30.org on behalf of
> public-list at lists.alberg30.org> wrote:
>
> Jim
> I agree that it's all about trimming foils, and all the helmsman's
> responsibility - but like so much of the America's Cup - that's
> rule-driven.
>
> Of course the goal of all the foil geometry, position , and potential
> dynamic control is identical to the Alberg 30's keel and rudder -
> balance
> hydrodynamic lift and drag against aerodynamic lift and drag with
> minimal
> drag. The foils add a much higher vertical component to lift the boat
> and
> reduce the drag. As you say, when you no longer are using hydrostatic
> balance, you must get pitch balance from the foils also.
>
> A simpler picture is a pair of horizontal foils that cant with heel, so
> they always lift against gravity, and a a pair of vertical foils that
> cant
> with heel and leeway, so their lift and drag matches the aerofoiils
> (sails)
> lift and drag. L-Foils are a compromise to stay within a certain
> number
> of moving foils. The L-Foils use a single foil to get vertical and
> transverse lift.
>
> The simpler picture allows you to separate the "flying" function from
> the
> optimal forward-speed function. I think you would ideally have separate
> controls for these two goals.
>
> The AC 42's can't do this, so helm must also fly!
>
> I would like to see these boats in some bigger waves and see how they
> control them!
>
> Mike
>
> On Wed, May 31, 2017 at 10:11 AM, Jim Mennucci via Public-List <
> public-list at lists.alberg30.org> wrote:
>
> > Can anyone add to my understanding of how the hydraulically driven
> > hydrofoils work on the Americas cup 42 footers now racing in Bemuda--
> > here's what I think i'm seeing:
> >
> > - In a way its kind a cool--going 30+ knots up and down wind doesn't
> > require much sail trim...hydrofoil trim is another matter. Talk
> about
> > changing sail boat racing as we all understand it. Trophy goes to
> team
> > that is best at hydrofoil control, in fact hydrofoil control is the
> only
> > area of boat design the is somewhat left to the syndicates to
> control on
> > their own. . Optimizing hydrofoil control maximizes speed.
> >
> > - unlike the 72 footers, the 40 footers will use hand controls i.e.,
> no
> > closed-loop feed-back controls for the hydrofoils--this is what I
> wonder
> > about? The hydraulic directional control valves used to pivot the
> foils
> > use some sort of electrically controlled linear actuator to open and
> close
> > flow to the hydraulic actuators, It would be easy to add some feed
> back
> > control to the electrical part of the valve and if they don't that's
> good
> > because of the additional skill needed to manually maintain stability
> >
> > - article I read says stored energy (accumulators) are not allowed
> and the
> > hydraulics must be provided by hand pump--hence they're always
> pumping
> > (like maniacs) to have fluid under pressure (must be a relief valve
> to
> > regulate pressure)
> >
> > - the article talks about 3 hydrofoil controls: Cant, lift and pitch
> are
> > the 3 names used.in the article.
> > - It sounds like cant angle corresponds to roll which is used
> to
> > add/control righting moment. Canting the wing off vertical tilts the
> > horizontal part of the wing which should result in some loss in lift
> making
> > an adjustment to the angle of attack to rebalance the lift--this is
> where
> > feedback control would be nice but making the helmsmen do the
> adjustments
> > in a manner that maintains foil stability adds old-fashioned skill
> to the
> > mix. Thoughts? pivoting the hydrofoil outboard adds righting
> moment
> > - lift control would pivot the hydrofoil in the pitch plane
> to
> > change angle of attack
> > - pitch control to me is the same as lift except its listed
> as a
> > separate function. So I wonder if the dagger board and the rudder
> foils
> > work in concert to change the pitch of the boat--much like bow and
> stern
> > planes on a submarine
> > - looks like linear hydraulic actuators are used to control 2
> rotational
> > degrees of freedom on the dagger board foils and a single actuator
> to pitch
> > the rudder foils.
> > - the foil controls are built into the helm wheel and its looks like
> they
> > run the system open circuit i.e., no feedback control. They hit
> buttons
> > built into the helm to open the directional control valves. So the
> > helmsmen is also the foil trimmer.
> >
> > any insight, thoughts appreciated
> >
> > Jim Mennucci
> > _______________________________________________
> > These businesses support your Association:
> > http://www.alberg30.org/store/A30supporters.html
> > Please support them.
> > _______________________________________________
> > Public-List mailing list
> > Public-List at lists.alberg30.org
> > http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
> >
> _______________________________________________
> These businesses support your Association:
> http://www.alberg30.org/store/A30supporters.html
> Please support them.
> _______________________________________________
> Public-List mailing list
> Public-List at lists.alberg30.org
> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
>
>
>
>
>
> ------------------------------
>
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