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[Brian60]

Or even very adept at puzzle solving boat builders?

I've got a problem I can't get my head around and would like some advice please, but I'd rather do it by pm and not open forum until I have it working properly.

This is not my video but posted here for demo purposes....

https://www.youtube.com/watch?v=v3cw7ttDjh4

I have already got this part solved, 360degree rotation controlled by a stepper motor and an arduino board for control, its the next step from this I am stuck on and want to discuss.

So if anyone fancies a few pm's please get in touch.

[roycv]

Hi Brian60, the technical stuff is the most interesting.  Why the secrecy of PM's?  Don't be shy we won't tell a soul.
look forward to more.
regards Roy

[malcolmfrary]

Hi Brian60, the technical stuff is the most interesting.  Why the secrecy of PM's?  Don't be shy we won't tell a soul.
look forward to more.
regards Roy

Just so.  Its the bits that don't work that we learn most from.

[Brian60]

Only because I would prefer to document something that works rather than something that does not - something that can be replicated if anyone else wanted to use it, rather than something that ends up as a pile of expensive junk.
 

However failing any interested takers, I'll have to consider putting the problem 'out there'

[Martin (Admin)]

couldn't the parrot help?   

[Netleyned]

Is this the rise and fall of the azimuthing drive ?


Ned.

[Brian60]

Is this the rise and fall of the azimuthing drive ?


Ned.

[cos918]

There is a group of modellers that meet every 2 years in Europe. All they model is off shore models . What you are on about has been done . Best bet is to  contact the group


John

[Umi_Ryuzuki]

You should probably just contact Brett, Cadmunkey on RCgroups.
He's in the Canadian Coast Guard, but might have time to share a bit of info.

 

Looking at power motors, with steering servo beneath connected to control board.
 

[Brian60]

There is a group of modellers that meet every 2 years in Europe. All they model is off shore models . What you are on about has been done . Best bet is to  contact the group


John

You are talking about the IOS group John, they have a meeting coming up in Germany. I don't ever recall seeing what I am attempting on any of their ships, 360 degree rotation yes - that is the easy part, I already have that sorted. Its getting the unit to retract into the hull and have it remain watertight which has me baffled.

You should probably just contact Brett, Cadmunkey on RCgroups.
He's in the Canadian Coast Guard, but might have time to share a bit of info.

 

Looking at power motors, with steering servo beneath connected to control board.
 

Thanks Umi, that is a neat looking installation, I'll send him a pm next time I'm on the forum.

[essex2visuvesi]

Shouldn't be too difficult. Think about the retractable bits on model subs for inspiration

[richald]

Brian, anybody,

Are there any images of a full size unit retracted into the hull ?
so I can get an idea of what you are trying to achieve.

Richard

[roycv]

Excuse me for asking the obvious question but if these are propulsion units why do they need to retract into the hull?
regards Roy

[derekwarner]

Evening Roy....hope you are back home safe ....

These retractable pods may not the primary propulsion units, but designed to act as GPS controlled 'constant' positioning thrusters and only lowered when the vessel is on station

Here on MBM about 18 months ago we saw a thread of a very large Chinese built support type vessel...it had two X X symbols by the bow but only one tunnel thruster tube visible

Some days later, a 1/2 sectional view of the vessel appeared which confirmed that the second X was actually a retractable thruster pod ...................

Well that's my guess for this current quest............. Derek

http://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&sqi=2&ved=0ahUKEwjWrMmf-sfMAhVj3KYKHbRWBXkQFggbMAA&url=http%3A%2F%2Fwww.rolls-royce.com%2F~%2Fmedia%2FFiles%2FR%2FRolls-Royce%2Fdocuments%2Fcustomers%2Fmarine%2Fpropulsors.pdf&usg=AFQjCNFsmdgw4AO_eInM1NMiPyInwmlejQ&sig2=grtUuoTmRFKWvX-vZcp6WQ&bvm=bv.121421273,d.dGY

[Ian K]

This looks a bit similar to my retractable, steering bow rudder arrangement.

The drive to the rudders are made through telescopic square sections, allowing the retract and drive. The full unit is supported on 2x slide beams and 2x sets of guide bushes.
The unit is lowered and raised via a rack and pinion system, through bevel gears, driven off a high torque servo.

I dont see any reason why my telescopic square section rudder drive method, couldn't be used as a continuous rotation drive line.

Hope this helps a bit!

Ian

[Brian60]

Excuse me for asking the obvious question but if these are propulsion units why do they need to retract into the hull?
regards Roy

Derek was spot on with his answer Roy. They are only lowered from the hull when station keeping for such things as ROV or dive operations are taking place or indeed for holding the ship next to a rig while the rigs jib operator cranes loads off the ship.

The entire system, the azimuth pod, bow/stern thrusters and main drives are all controlled by a very sophisticated GPS system, that will hold the ship on station to within 1 metre.

[Umi_Ryuzuki]

The Germans are doing it like this,...

https://www.youtube.com/watch?v=OHN9-RssyOc&index=4&list=FLKMwv7sXw6Ny9DnLFj0semg

Using the IMTH module which provides combines throttle and steering across the two axis joystick.
http://imth.de/index.php/en/categories/product/view/1/58

IMTH Video at transmitter, joystick, and "Co Pilot" add on.
http://imth.de/index.php/en/videos-2?showall=&start=6

I have often pondered and "mind" engineered the retractable thruster, but it is a tough one to
wrap your brain around. The retractable bow rudder is a really nice bit of engineering.

 

[Brian60]

Umi the Germans make it easy due to using 1:50 as a scale. I do believe they actually build a brushless motor into the azipod, at least the Dutch take this method as being the easiest to accomplish. Apparently ( I saw the demo) brushless motors can run immersed in water with no problem! I can't go this route as building at 1:72 the azipod is only 12mm in diameter, way too small to fit a motor in to.

I won't actually have any control over this thruster (if everything electronic works out!) Once activated by TX I'm hoping that a gps system will take over and act as a dynamic positioning system, allowing other functions to take place. This is going to be a long build, but at the moment its collecting all the info to make things go smoothly.

[Umi_Ryuzuki]

Most of the German schottels are geared, as are the ones in the IMTH videos.
Bauer retails many of them. http://www.bauer-modelle.de/modules/wsShop/index.php?cat_id=83511&location_id=151

I know of one person, PeterS., building brushless motors into his Azipods for an Icebreaker




And this a Japanese thruster, is the smallest I know of, it is a small brushed motor in the water.
 
https://www.youtube.com/watch?v=-hy11m_HFC4


Not much help with retractability though... 

[roycv]

Hi Derek thank you for your interest.  I had a good trip back but it takes me 4 days to get over the jetlag, I am OK going though.  Had a good time as well.
Thanks for the info on station keeping, most interesting.
kind regards Roy