Hunton/ilmor Build

[peterunwin]

Originally Posted by Tony Davis

I take it that your not concerned about this boat conforming to CE regulations then?

Hi Tony,
My proposed steering system seems to have opened a "can of worms"!!!
1. It is my understanding that boats built for racing do not require CE marking.
2. It is also my understanding that prototype & test components do not require CE marking because you don't know what the final spec will be until you have signed it off.
3.As all the components used in this system are individually CE marked & are all from highly respected manufacturers, once development is finished & the relevant safety criteria met i wouldn't see a problem of getting a CE mark anyway.

Peter

[Jon Fuller]

Also, a 'home completion' boat doesn't need to conform to CE, or at least it didn't used to when I built mine.

[peterunwin]

Originally Posted by Jon Fuller

Bah, stuff all that H&S Bollox, it's crushing us all. I think it looks like great fun. Well riden/driven. do you have two wheels as well, or just the 4?

Hi Jon,
I am afraid i only have 4 wheels at the moment, have had 2 wheelers all my life but having had a succession of car drivers trying to knock me off!! i decided to give them up, but having recently visited the XCEL boat show & saw the Ducati street fighter on one of the stands i could be sorely tempted.

Peter

[Boatless-Again]

Originally Posted by peterunwin

Hi All,
Been quite busy over the last week or so designing engine mounting supports.Awaiting quotation from carbon fibre manufacturer, also been designing steering control system which has taken quite a lot of time & effort finding appropriate components. As you probably guessed the hydraulics side of it is no problem to us at all but the electronics to control the hydraulics has proved to be the headache,but i think we are now sorted so here is a brief outline of how it will work.
Each engine is fitted with a power steering pump which will feed oil into a fully proportional directional control valve the outputs of which are connected to the steering cylinders.The electronics side will have a rotary twin track transducer mounted in the steering column & two of the hydraulic cylinders will have linear transducers both feeding information to a programmable ECU, as this is a fly by wire system we will use dual components interacting with each other to make it as safe as possible.As all parameters are programmable we will be able to change the steering ratio giving plenty of feel in the central position gradually ramping up to give better low speed maneuverability & docking manners.Also we will build in self centering so it will be much more car like to drive.I am also looking at the possibility of tabs, trims & throttles all being steering wheel mounted, so we will be constructing a bench test rig in the near future.

Peter

Is this your system or Ilmor's system? I know that Morse Controls was making a electric hydraulic steering system for the outboards years ago, but have not heard of anyone trying this on a more performance related application.

[peterunwin]

Originally Posted by Boatless-Again

Is this your system or Ilmor's system? I know that Morse Controls was making a electric hydraulic steering system for the outboards years ago, but have not heard of anyone trying this on a more performance related application.

Hi Boatless-Again,
The steering system is my own design using a selection of high quality hydraulic & electronic components.I know fly by wire seems to frighten a lot of people but there are many benefits to be had, so i think it is worth the time & effort to write a suitable program for our steering ECU which will be by far the most costly part of the installation. It is also worth considering that most of our aviation is fly by wire with built in redundancy & so is a lot of the 5 axis machine tools both of which are far more complicated than steering a boat!.So whilst i don't expect to be perfect first time out i really don't see any major stumbling blocks on the development side."BUT IF AT FIRST YOU DON'T SUCCEED TRY AGAIN"!!!

Peter

[Jon Fuller]

Originally Posted by peterunwin

"BUT IF AT FIRST YOU DON'T SUCCEED TRY AGAIN"!!!

Peter

Once released from the infirmary!

Only kiddin.

You don't get too many 5 axis machines emersed in the briney though, or aircraft, at least no intentionally.

Just out of pure interest Pete, what advantages do you see in this system, over a conventional, simple Char Lynn type hydraulic helm unit and engine driven pump (other than a great technical challenge)

[PhatFrank]

Originally Posted by peterunwin

1. It is my understanding that boats built for racing do not require CE marking.

CE marking is necessary if you intend to sell the boat as a "production" model within the EU/EEC. Building a one-off, prototype or race boat (for your own use) is as such not required to be CE marked.

One "reputable" boat builder here in Norway lost a lawsuit against a customer on this basis. The customer had managed to completely bugger a brand new boat within a couple of days after buying it, and although he appeared to be losing the lawsuit due to his reckless use he eventually won (and got all his money back) as the boat was not built to CE regs...

[Scand]

The Stormway case?
I think they lost the case as the boat was incorrectly CE marked, and therefore not be legally sold. Nice enough boat though.

Originally Posted by PhatFrank

CE marking is necessary if you intend to sell the boat as a "production" model within the EU/EEC. Building a one-off, prototype or race boat (for your own use) is as such not required to be CE marked.

One "reputable" boat builder here in Norway lost a lawsuit against a customer on this basis. The customer had managed to completely bugger a brand new boat within a couple of days after buying it, and although he appeared to be losing the lawsuit due to his reckless use he eventually won (and got all his money back) as the boat was not built to CE regs...

[peterunwin]

Originally Posted by Jon Fuller

Once released from the infirmary!

Only kiddin.

You don't get too many 5 axis machines emersed in the briney though, or aircraft, at least no intentionally.

Just out of pure interest Pete, what advantages do you see in this system, over a conventional, simple Char Lynn type hydraulic helm unit and engine driven pump (other than a great technical challenge)

Hi Jon,
Could almost be worth engineering a mishap for all the attention from those gorgeous nurses
All the electronic components are waterproofed to 2metre submersion so i think they should be pretty safe & reliable.As to the main benefits that i see the list is very long but i will cover a few.
1. The orientation of the steering wheel will remain in syncrinization with the drives something that i think is very important when driving anything very quickly.Can you imagine driving a racing car where each corner you come to the steering wheel is in a slightly different position, dialling in corrective lock accurately would be extremely difficult, also when mounting steering wheel controls for other functions i.e. trim & tab controls you always know which way to press the switch as their orientation doesn't change.
2. Also by hooking into engine revs & speed i can vary the steering ratio so at low speeds i can have for instance one turn lock to lock for good maneuverability gradually increasing the turns lock to lock as the speed increases.
If you would like to PM me your phone number i would be more than happy to discusss this topic at length.

Peter

[Jon Fuller]

All sounds very good, and certainly interesting.

The 'wheel creep' thing is most annoying, agreed.

Am currently in Portugal, back on Sunday, will send my number and hopefully speak in the coming week.

Jon

[jw.]

Originally Posted by peterunwin

If you would like to PM me your phone number i would be more than happy to discusss this topic at length.

Peter

Peter, if it's not to be a secret, it would be nice to follow the discussion here. A good number of us are interested in technical stuff and don't regard it as TMI.

[Paul E]

I's also like to see how it's all going to be done, it sounds like a great idea if it can be made fail-safe.

You mentioned some kind of RPM/Speed sensitive steering, which I presume would mean the steering ECU and Engine ECUs will be able to communicate. What about having a system that shuts down the engines in the event of any problem with the steering system?

[timtap]

This all sounds very Area 51 Skunk works Tecnology for Boats !!!

[Scand]

Originally Posted by peterunwin

Hi Boatless-Again,
The steering system is my own design using a selection of high quality hydraulic & electronic components.I know fly by wire seems to frighten a lot of people but there are many benefits to be had, so i think it is worth the time & effort to write a suitable program for our steering ECU which will be by far the most costly part of the installation. It is also worth considering that most of our aviation is fly by wire with built in redundancy & so is a lot of the 5 axis machine tools both of which are far more complicated than steering a boat!.So whilst i don't expect to be perfect first time out i really don't see any major stumbling blocks on the development side."BUT IF AT FIRST YOU DON'T SUCCEED TRY AGAIN"!!!

Peter

Very good build tread. I like the idea of using fly by wire steering.
On the Yellowfin VSD project we went through quite a lot of development on fly by wire steering. These drives were fixed variable pitch surface drives, and steering was done by differential pitch, so no rudder, or angling the drives in the traditional sense to steer. The pitch was hydraulically actuated. So quite different to your drives, but the fly by wire bit might have some common ground.

The system was configured with an external programmable processor that controlled both the engine ECU and the drive system, with the pitch actuation.

For steering we went through a number of different approaches, making steering sensitivity, or the amount of differential pitch to be put on, dependent on boat speed, engine speed, and then a mix of the two. This did not give satisfactory results. What worked best, and what we ended up with, was to incorporate a yaw senor in the steering hardware. Quite roughed, precise units same are now commercially available, at a reasonable cost. The steering was set up so the helm basically gave a yaw rate, or rate of turn, demand to the processor. The processor would then alter the differential pitch to achieve the demanded rate of turn. In principle a given helm input would give the same rate of turn (deg/sec) regardless of the boat speed. Is would also have the same rate of turn regardless of it was tuning into or with the wind. The yaw sensor approach also gave some protection against spinning out and assisted course keeping. When it was set up it worked really well. One of the main challenges was to try to achieve good direct feel of the steering, but this was mainly achieved by tweaking the software.

We never tested it at the speeds you are planning to go at though.

[Boatless-Again]

Originally Posted by Scand

Very good build tread. I like the idea of using fly by wire steering.
On the Yellowfin VSD project we went through quite a lot of development on fly by wire steering. These drives were fixed variable pitch surface drives, and steering was done by differential pitch, so no rudder, or angling the drives in the traditional sense to steer. The pitch was hydraulically actuated. So quite different to your drives, but the fly by wire bit might have some common ground.

The system was configured with an external programmable processor that controlled both the engine ECU and the drive system, with the pitch actuation.

For steering we went through a number of different approaches, making steering sensitivity, or the amount of differential pitch to be put on, dependent on boat speed, engine speed, and then a mix of the two. This did not give satisfactory results. What worked best, and what we ended up with, was to incorporate a yaw senor in the steering hardware. Quite roughed, precise units same are now commercially available, at a reasonable cost. The steering was set up so the helm basically gave a yaw rate, or rate of turn, demand to the processor. The processor would then alter the differential pitch to achieve the demanded rate of turn. In principle a given helm input would give the same rate of turn (deg/sec) regardless of the boat speed. Is would also have the same rate of turn regardless of it was tuning into or with the wind. The yaw sensor approach also gave some protection against spinning out and assisted course keeping. When it was set up it worked really well. One of the main challenges was to try to achieve good direct feel of the steering, but this was mainly achieved by tweaking the software.

We never tested it at the speeds you are planning to go at though.

What is happening the "Yellow Fin"?

Is the company closed? Open? ??

[larby]

I'm pretty sure yellowfin went under a while back.

As for the variable steering, i can see that being a bit odd. In the same way as you mentioned steering creep being hard to live with due to you never knowing where the drives are in relation to the wheel.
Surely it'll be hard to know what effect a turn on the wheel will have at any given time, due to the variation. It's possible (and essential) to 'learn' how much effect a certain turn of the wheel will have when the ratio is constant, but i can't see how someone could get used to how much to steer when the ratio is variable by either speed or where it is in the arc of turn, let alone both. Imagine running into a straight at high speed, using little taps to keep the boat level, then slowing for a corner and turning sharply. Suddenly the little taps required to keep the boat from becoming a hat during the corner are totally different, depending on how hard you're turning at the time. I don't like the sound of that!
That said, as i used to be in engineering i love the sound of the steering idea, and as it's all ecu controlled it can be changed around to suit as required! I could well be totally wrong with all of the above!
Would be great to hear all the information on here too!

James

[Scand]

Originally Posted by Boatless-Again

What is happening the "Yellow Fin"?

Is the company closed? Open? ??

http://www.ibinews.com/ibinews/newsd...19ibinews.html

I left the yellowfin just over a year ago now.

[peterunwin]

Originally Posted by Paul E

I's also like to see how it's all going to be done, it sounds like a great idea if it can be made fail-safe.

You mentioned some kind of RPM/Speed sensitive steering, which I presume would mean the steering ECU and Engine ECUs will be able to communicate. What about having a system that shuts down the engines in the event of any problem with the steering system?

Hi Paul,
Yes as you mentioned it would be possible to engineer in a limp home mode to the engine ECU'S which will be done if i ever decide to make this into a commercially available product.

Peter

[peterunwin]

Originally Posted by larby

I'm pretty sure yellowfin went under a while back.

As for the variable steering, i can see that being a bit odd. In the same way as you mentioned steering creep being hard to live with due to you never knowing where the drives are in relation to the wheel.
Surely it'll be hard to know what effect a turn on the wheel will have at any given time, due to the variation. It's possible (and essential) to 'learn' how much effect a certain turn of the wheel will have when the ratio is constant, but i can't see how someone could get used to how much to steer when the ratio is variable by either speed or where it is in the arc of turn, let alone both. Imagine running into a straight at high speed, using little taps to keep the boat level, then slowing for a corner and turning sharply. Suddenly the little taps required to keep the boat from becoming a hat during the corner are totally different, depending on how hard you're turning at the time. I don't like the sound of that!
That said, as i used to be in engineering i love the sound of the steering idea, and as it's all ecu controlled it can be changed around to suit as required! I could well be totally wrong with all of the above!
Would be great to hear all the information on here too!

James

Hi James,
It's all in the subtlety of the programming. It is probably a little known fact that most cars thes days are fitted with some form of variable ratio steering racks but so suttle is the change in ratio most drivers don't even notice.The reason it is done on cars is to make the steering less nervous around the straight ahead position but still not require loads of input when you come to a corner.Some porsche & bmw models have gone one stage further by using a system called servotronic which is speed sensitive giving good high speed feed back & feel gradually decreasing the number of turns lock to lock as the speed falls so at parking speeds you rarely need more than half a turn even for the tightest of maneuvers, works extremely well & is very easy to get used to.
Back to the boat steering as previously mentioned it is all in the steering system programming being written subtlely enough to seamlessly change the steering ratio as the speed rises & falls.We will also engineer in the maximum amount of steering lock the boat can take at any given speed which will be arrived at by water testing so that in the event of being thrown around in rough water you accidentally apply more lock than the boat can take at that given speed the steering system will only apply the safe amount that bit of the testing should be fun as i will test it very close to the limits.

Peter

[motorvator]

I think you need to go the whole hog and install one of these too.