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Author Topic: My 12 foot Gato class submarine!  (Read 156407 times)

Subculture

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Re: 12 foot gato class submarine video
« Reply #175 on: November 18, 2011, 01:48:36 PM »

It did. I made a tail up out of some thin epoxy glass sheet, which flexes, and rigged it to a servo set in small foam float with a keel for stability.

The tail was submerged but the float remained on the surface, this was to test the propulsion efficiency.

Conclusion, it worked, but it was rather sluggish, and turning was a bit laboured. If the speed could be increased, then it would be much improved, but I don't think that is going to be very practical if using a normal servo. I may give it another go with some fancy servos I got which use magnetic inductors in place of carbon pots. These servos are also blindingly quick, so may try a Picaxe 08M to swing it at a higher speed, and see where that goes. Not sure what could be done about the wide turning circle. The multi-jointed fish are able to turn in their own length.

Davy1

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Re: 12 foot gato class submarine video
« Reply #176 on: November 18, 2011, 03:16:32 PM »

Thanks for the update after these many years and how is the "Yellow Submarine"?
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Subculture

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Re: 12 foot gato class submarine video
« Reply #177 on: November 18, 2011, 04:35:06 PM »

The Yellow submarine is progressing, currently working out the gimbal prop assembly for pitch control as there are no hydroplanes on this rascal. It's been used to excellent effect on the Disney Nautilus, so it should work well on the YS too.

sub john

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Re: 12 foot gato class submarine video
« Reply #178 on: November 18, 2011, 08:32:53 PM »

Reply#173
 HI Mike, What you need to connect to servo amp is called a H bridge drive circuit it will basically have 4 fets in it and needs to be logic level on gates of fets which will be 5volts, i can draw up circuit showing you how to do it if you won't. I might have some servo amps lying about some where i will have to have a look to see if i can find them
                            John
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MikeA

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Re: 12 foot gato class submarine video
« Reply #179 on: November 19, 2011, 12:58:11 AM »

I would very much appreciate that. if you could draw me up circuit diagram and if possible make a one up and a take some pictures.  :-))
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sub john

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Re: 12 foot gato class submarine video
« Reply #180 on: November 19, 2011, 05:46:37 PM »

Reply#179
HI Mike, At the moment i am up to my neck in electronics just give me a few days and will draw circuit up for servo speed controller and when i get time i will knock it up on my developing board and get it to rock and roll, what voltage do you won't it to work on i think you said 7.2 VOLTS can be made to work quite easy on 12VOLTS need to know how many AMPS you are going to use as this will govern how many fets you need on H bridge drive circuit
    John
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MikeA

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Re: 12 foot gato class submarine video
« Reply #181 on: November 20, 2011, 09:43:00 AM »

hiya. yeah of course when you got some time.  as far as voltage is concerned i have a handfull of batterys ranging from 7.2 to a 3s lipo which measures about 12.6v on my multimeter. I dont know if its possible but if the esc was manufactured to work at 12v would it also work on 7.2?  Also i think a good allrounder amp rating will do. I reckon 40 amps continuous will be plenty of head room for a range of motors.
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sub john

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Re: 12 foot gato class submarine video
« Reply #182 on: November 20, 2011, 07:10:33 PM »

Reply#181
HI Mike,  circuit for speed controller can be made to work on 12.6 VOLTS 3 cell lipo and all so be made to work on 40AMPS, have you thought about voltage cut out voltage for speed controller

Said a few days ago was going to go out and try radio link for under water again, instead of taking CB radio out  of sub reworked and modded another CB radio what seemed like a good idea instead of taking one out of sub any way went down canal today put transmitting Ariel for 27MHZ for controlling sub in the water and walked away from Ariel in the water, watching signal  on meter for  signal strength on CB radio walked about 100FT away then putting receiving Ariel in the water as well  and was still receiving signal full scale, in the end i was about 500 FT away down the canal, signal strength on meter had gone down quite a bit but when i put Ariel back in to the water again the signal went up quite a bit which said that the signal was having to travel 500FT through water from transmitting Ariel to receiving Ariel  i think i can now say that it works. As 500FT through water is a long way and it was receiving a very strong signal like i said before it all takes time to design but it does seem worth it now.


Had to make ATU unit to work under water as Ariel does change from being made to work in the bath to being in the canal but it has got interesting but have spent a long time on this
   John
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MikeA

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Re: 12 foot gato class submarine video
« Reply #183 on: November 20, 2011, 09:01:25 PM »

Reply#181
HI Mike,  circuit for speed controller can be made to work on 12.6 VOLTS 3 cell lipo and all so be made to work on 40AMPS, have you thought about voltage cut out voltage for speed controller

Said a few days ago was going to go out and try radio link for under water again, instead of taking CB radio out  of sub reworked and modded another CB radio what seemed like a good idea instead of taking one out of sub any way went down canal today put transmitting Ariel for 27MHZ for controlling sub in the water and walked away from Ariel in the water, watching signal  on meter for  signal strength on CB radio walked about 100FT away then putting receiving Ariel in the water as well  and was still receiving signal full scale, in the end i was about 500 FT away down the canal, signal strength on meter had gone down quite a bit but when i put Ariel back in to the water again the signal went up quite a bit which said that the signal was having to travel 500FT through water from transmitting Ariel to receiving Ariel  i think i can now say that it works. As 500FT through water is a long way and it was receiving a very strong signal like i said before it all takes time to design but it does seem worth it now.


Had to make ATU unit to work under water as Ariel does change from being made to work in the bath to being in the canal but it has got interesting but have spent a long time on this
   John

What id like it to be able to do is have the abillity to use a range of voltages if its possible. between 7.2 and 12v.  i dont want to add a lipo LVC just yet i can learn that later.

the batteries i have that i primarily use are 7.2 and 8.4 nimh. I have a 3s lipo too but i only have one and use that for one boat and i suppose ill get more at a later date.


ok now your sub.  It seems like this is a huge achiement and i have to admit its beyong my comprehesion.  can you help me get to grips:

 i presume that this is for the video link as you have allready got sub controll right?

did you have the video link working when you made the model 20 years ago?

what was the problem with it to make you develop it further?

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sub john

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Re: 12 foot gato class submarine video
« Reply #184 on: November 21, 2011, 06:18:30 PM »

Reply#183
 HI Mike,  1,   Speed controller can be made to work on all voltage packs you use plus lipo 3 cell pack

2,  Yes it is a huge step in being able to put Ariel in the water

3,  If you stood at the bank side with transmitter in your hands and you had sub 30FT out from the bank side and had it 10FT down under water you would loss radio contact with the sub but with the TX  Ariel designed to be in the water, and with it being able to transmit 500FT under water and still got a very strong signal i think it is a vast improvement  i am quite pleased with the end result

Need to get same result with video link
                       
                           John
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MikeA

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Re: 12 foot gato class submarine video
« Reply #185 on: November 21, 2011, 11:02:35 PM »


3,  If you stood at the bank side with transmitter in your hands and you had sub 30FT out from the bank side and had it 10FT down under water you would loss radio contact with the sub but with the TX  Ariel designed to be in the water, and with it being able to transmit 500FT under water and still got a very strong signal i think it is a vast improvement  i am quite pleased with the end result

Need to get same result with video link
                       
                           John

RIGHT I get where this is going now lol. It was kind of hard to understand your solutions when i didnt understand the problem but now i can see how this is something of a huge leap forwward. Well done m8. I thought id look up just how much pressure water is at 500 ft and its 216 psi!! I realise you wont be going this deep though lol. So what happened with low rf you were experimenting with? 27mhz is just normal band?? whats the difference between your radio and a standard 27mhz shop bought one?


I got some used but working servos on the way in the post. I appreciate your help
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Davy1

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Re: 12 foot gato class submarine video
« Reply #186 on: November 22, 2011, 01:51:53 PM »

Congratulations John. That is one heck of a breakthrough!
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sub john

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Re: 12 foot gato class submarine video
« Reply #187 on: November 22, 2011, 08:08:35 PM »

HI Mike
 You asked what the differences is between my 27MHZ TX for sub and a shop brought one, mine has got about 90 functions a shop brought one would not controll this sub of mine as it has not got enough channels it was all scratch built a long time ago, Plus my antenna out put is nothing like a standard TX unit plus i can switch to other bands with it. The range that i got down the canal on 27MHZ with Ariel in the water if you was to use LF being low frequency the radio would travel a lot further under water plus at LF you get a thing called ground wave

On your last post you said that you have got some servo amps coming what make of servos are they

NO problem with trying to help you if you won't to learn any time mate
 All the best John
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sub john

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Re: 12 foot gato class submarine video
« Reply #188 on: November 22, 2011, 08:14:10 PM »

Reply #186
 HI Davy 1 Yes it did seem to work antenna really well under water i am sure that i could have done 1000FT as signal was so strong at 500FT away it will be interesting to try it on LF  band and see what range i get i am quite sure i will be able to get from one end to the other on Charnwood waters
  John
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MikeA

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Re: 12 foot gato class submarine video
« Reply #189 on: November 22, 2011, 08:27:17 PM »

hi john so what did u change then to make it work better? in a simple explanation lol

also i got the servos today they are JR standard servos. They have been modded by removing the axle between the output shaft and the position pot. i got them for a pound each plus 1.80 pnp. I tried them today and out them on my throttle channel, works fine.
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sub john

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Re: 12 foot gato class submarine video
« Reply #190 on: November 23, 2011, 06:59:33 PM »

Reply#189
 HI Mike,  If you look on page 3 Reply#131  This unit is software controlled and will automatically tune antenna from 1MHZ all the way up to 30 MHZ in 5 KHZ  steps if needs be. All software and electronics is in the brass screened box inside the unit

Good news on getting JR servos they should do the trick
     John
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MikeA

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Re: 12 foot gato class submarine video
« Reply #191 on: November 23, 2011, 07:27:38 PM »

oh i remember that. trying to understand it makes my brain hurt  {:-{ %%

i dont know what else i need though john just got servos for now.
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sub john

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Re: 12 foot gato class submarine video
« Reply #192 on: November 25, 2011, 06:37:30 PM »

Reply#191
 Hi Mike,   Shouldn't worry about any other bits for servo speed controller until I have worked it out, one of the other jobs that I'm having to do at the moment is help my son build a custom built computer case, all i got was help me i can not do it myself so i end up having to sort it out
   ALL THE BEST JOHN
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MikeA

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Re: 12 foot gato class submarine video
« Reply #193 on: November 25, 2011, 11:40:21 PM »

ok fair enough. Sounds like fun, is your electrical talent hereditary?
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sub john

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Re: 12 foot gato class submarine video
« Reply #194 on: November 26, 2011, 06:11:48 PM »

REPLY #193
HI Mike yes i think so Mike,    Hope to go down the canal and try low frequency radio link under water, this should be interesting to see what happens
      All the best John
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MikeA

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Re: 12 foot gato class submarine video
« Reply #195 on: November 26, 2011, 06:40:10 PM »

I inherited my mechanical understand from my dad and now my two year old son seems to be getting the hang of it. best of luck with that endeavour at the lake. 

I thought you had allready tried low frequency?? and the result was to use 27mhz??

how abou the video link hows that coming?
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sub john

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Re: 12 foot gato class submarine video
« Reply #196 on: November 27, 2011, 08:13:20 PM »

HI David f
    Antennas for under water i do seem to be getting some where now,  It seems like people are struggling to see the benefits of a lot more range under water with TX Ariel being in the water i can see how it must be hard to grasp but if you think it was traveling through 500FT of water and was a very strong signal being received you guys must admit it has got to say some thing and it would have gone a lot further under water and plus i was not knocking out a lot of RF, but could have turned the power right up.
                All the best John
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MikeA

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Re: 12 foot gato class submarine video
« Reply #197 on: November 28, 2011, 03:55:16 PM »

I hope i wasnt included in that statement about people not understanding the necessity of long range underwater  :((
When the feedback works and you got the under water camer going the footage will be amazing.
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sub john

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Re: 12 foot gato class submarine video
« Reply #198 on: November 28, 2011, 06:35:34 PM »

Reply#197
HI MIKE, No Mike didn't include you in the last statement, didn't have time to go down the canal at weekend weather was to bad it's not really the time of year to have your hands in water out side. I do need to test low frequency radio under water have tested as a radio link through the air and system works fine. When you go to low frequency's you have a skywood wave but also have a ground wave but as the frequency goes low the ground wood wave becomes stronger this ground wood wave should work in my favor once the Ariel is in the water its quite possible that it could have a massive range. Came across a article on the internet about radio waves under ground it was quite interesting  this what I'm doing with low frequency i would think that quite a few radio hams would be interested in it


Haven't forgot about your circuit for speed controller as soon as i get time i will do it for you.
      All the best John
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MikeA

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Re: 12 foot gato class submarine video
« Reply #199 on: November 28, 2011, 06:55:16 PM »

i went down to the lake yesterday it was freezing lol. Wouldnt have been so bad if my boat actually worked aswell as i had hoped it would. I didnt think you had forgetten bout esc, new u was busy anyway.  :-))
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