R/C sub regulator project - An university midterm project underway

[jsl]

[color=#000000]Our university midterm project is now underway. I intend to document our progress in here. We hope that people will find this thread interesting and worth to look at.

The project is now in its 5th week, and I intend to update this thread every week or so. I will try to add pictures as well.

Condensed hard facts]

[jsl]

Stage 1]

[color=#000000]Stage 1]

[jsl]

Stage 2]

[color=#000000]Stage 2]

[jsl]

Stage 3]wtc finished

Just a picture

Stage 3]wtc finished[/url]

Just a picture of an Engel piston tank]Engel piston tank[/url]

A piston tank sitting in the rack and a wtc plug with seal]Piston tank, rack and wtc plug[/url]


We have then tested and approved the following sub-systems]Accelerometer - Angle detector[/url]

- The H-bridge motor drivers]Propulsion motor, test shaft, prop and H-bridge[/url]

- The low battery detector and water detector has also been succesfully tested. No snapshots I'm afraid..

Finally a shot of the heart of the regulator. An Atmel microcontroller (and two spares)]Atmel microcontrollers[/url]

We only recieved the pressure sensor recently, and it is the only hardware subsystem left to be tested.

As previously mentioned, alle of the above subsystems will be an integrated part of the regulator.

[wingtip]

interesting...i could use something similiar

interesting...i could use something similiar if you plan on marketing these items

[koeze]

Hey,

Interesting project you got going

Hey,

Interesting project you got going there.
One little bit of advice.

A lot of people seem to think that a sub needs negative bouyancy to dive. In reality the only thing that that does is sink it. A neutrally bouyant sub can reach any depth by using its depth rudders. It does not need to take in extra water to dive deeper.

Once a sub is neutrally bouyant there is no need to have extra capacity in the tanks. You could however need a bit extra to use as a trimtank for levelling the boat but inho 1/3 of the total volume is way too much. You'd be much better off using all extra bouyancy for emergency surfacing.

I'm really interested in how things work out.

Best regards,

EJK



Edited By KOEZE on 1110986596

[jsl]

Hey KOEZE,

Thanks for the advice,

Hey KOEZE,

Thanks for the advice, and you're right. A sub can go on the planes and propulsion to any desired depth.

We decided on the one-third/two-thirds approach because we want the sub to be able to do fully static diving and surfacing without using the prop. The regulator we're working on is designed to be as versatile as possible. This regulator for example be installed in a ROV using either Engell Piston tanks, other heavy duty piston tanks, or even a third system capable of controlling ballast. For the regulator, it doesn't really matter what system is used for ballast control, as long as it can be precisely controlled with the connections at hand. The regulator will also do its best to reach the desired positions if we change the amount of dead ballast. If changes are to dramatic, it probably can't deliver an acceptable result, but it will try.

For a ROV it would save a lot of energy if the unit could sink all the way to the bottom and then adjust for neutral bouancy.

Actually.. Some of the "static divers" I have seen in here, are only static "ascenders". They are trimmed so that they have a slight positive bouancy, and can't dive without forward motion.

We have also opted for the 1/3 - 2/3 solution to be able to change the angle of the sub when static. For that we need some water left in the tanks to both change angle and maintain depth at the same time.

Hope this gives a bit more insight.

I plan on an update for the past two weeks on friday. We've made vast progress in the past two weeks. Most of the hardware is in the final stages now.

Jacob

[jsl]

Update]http://www.subcommittee.com/forum/icon_smile.gif ), and with that

Update]http://www.subcommittee.com/forum/icon_smile.gif[/img] ), and with that new capture card, we'll be able to grab video in good quality. We'll post footage in here as soon as we grab it. A camera as a periscope is a "must have".

Two 12 volt 3000 mAh batteries have been aquired. They will power the sub for extended periods of time. Again I must point out that using an old high torque, low speed, low current, silent tape recorder motor is a very good idea. It moves large quatities of water and only uses 500 mA. Theoretically 12 hours at full speed will hopefully be quite a distance.

A good deal of the tubing have been done with regard to the piston tanks. All tubes linked to open water will have their openings in one of the end plugs.

The plugs are thick enough to make sure that all connections to open water can be realised through the side of one end plug. Should we decide to add perhaps a propulsion compartment to the other side of the cap, it will still be completely water proof. This way we can avoid drilling even a single hole in the WTC. It will also be a piece of cake to dismantle the WTC and pull all of the internals, mounted on the rack, out.

Next week will be Easter holiday, and the project is resting. The week after that we hope to have the hardware tested and approved. Then the programming of the regulator itself begins.

Sorry about mis-types and missing pictures. Will include them in the next update.

NOT the mis-types, if I can help it

Happy holiday,

Jacob

[jsl]

Update]http://www.subcommittee.com/forum/icon_smile.gif

Next week will be programming

Update]http://www.subcommittee.com/forum/icon_smile.gif[/img]

Next week will be programming and finishing up the H-bridge driver PCB. This programming of the microcontroller will link it to the peripheral systems. It needs to be able to sense the signals from all of the sensors first, to later act on them according to its programming.

The regulator itself, which will regulate depth and angle, can only be programmed once all of the underlying software is in place. We decided in this project to program a regulator for a small sub. Actually, it will probably only be the last few weeks well work on that.

We have had a lot of minor bugs in the entire design process. A wire not where it was supposed to be, LEDs on the wrong side of the curcuit board, plugs wired backwards, and so on. Each little bug or problem has been solved all along, so that the final version will hopefully be flawless. We have learned why designers end up doing serveral versions before they're satisfied.

I can't wait to have this sub finished. It's going to be awesome! I'm sure a nice outer hull will also come along at some point.

Can't wait to put a cam on the sub when it will face it's ultimate test. The 25 meter descent into "The Abyss".

Jacob

[jsl]

Forgot the snapshots!

Top layer of

Forgot the snapshots!

Top layer of regulator

Bottom layer of regulator

Upper layer of H-bridge driver PCB

Jacob

[jsl]

Its friday and once again

Its friday and once again time for another update on our project.

Update]Assembled regulator hardware[/url]

The serial communication also works now. This is the interface either a laptop or another microcontroller will communicate with the regulator. We will also use the serial interface to download the data that the regulator logs in the testing phase. All parameters can be updated or adjusted through the serial interface.

A little progress on the WTC has been made. The regulator has been mounted in the rack inside the WTC. Lots of room to spare. The regulator should be able to fit inside a 3" wtc, maybe even a 2.75" WTC.

Regulator fits with lots of room to spare

Conclusion]http://www.subcommittee.com/forum/icon_cool.gif[/img]

[Guest]

Are you intending to market

Are you intending to market this board when development is completed?

It sounds like you are producing something quite unique. Sure others have produced devices that control depth and angle, but this the first time I've seen it all put onto one board.

I think the more experimentally minded model submariners would be very interested in obtaining a board.

Either that or perhaps you would consider releasing the details of the design for those handy with a soldering iron.

Good stuff!


Andy

[jsl]

Andy,

We planned our midterm project

Andy,

We planned our midterm project to reflect a real life engineering challange, only that we ourselves defined the engineering problem to which we had to design and manfacture a solution.

We have designed the Regulator to be a truely flexible system, able to regulate anything from a R/C submarine to a semi-proffessional ROV or submersible. An operational depth of 25 meters emphasizes this.

The conclusion of this midterm project will yield a Regulator ready to go into production, along with a complete datasheet. With so many different applications in mind, the project includes the writing of an extensive detailed datasheet, describing all features and possible upgrades.

so.... In about 9 weeks the regulator should be ready to go into full scale production. Of course, it never will, but we will have done a project as realistic as they get in real life.

But it would be a shame and a waste to let all that effort sit in a dusty university shelf... We'll manufacture regulators on demand, but never in larger scale.

Once the Regulator itself is complete, it is easy to supply software upgrades to suit demand. We designed the Regulator to make it easy for anyone to get to the microprocessor and gently pull it out. A software upgrade would just be a new processor with upgraded software delivered by mail. As easy as it gets...

Oh.. by the way... I don't think anyone want to try and build this thing themselves, trust me! You have no ide af how much curcuitry has been cramped into those two small boards.

Honestly, I think that unless someone is a pro, it is very unlikely that they'll ever complete a Regulator from scratch. Even if someone does manage to complete it, they have no way of testing it. It's so easy to make a tiny mistake somwhere and you need the know-how to ever have a chance of finding the bug.

I have no idea of a possible price. It'll depend on how many man-hours go into manufacturing and testing each unit. It'll have to be decided later.

Another scary thought... A quick head-estimate tells me that at this point we have thrown about 900 man-hours into the development of the Regulator. :O

There I did it again... Another mile-long post...

Jacob

[jsl]

The SHORT-SHORT list of what

[color=#000000]The SHORT-SHORT list of what features the Regulator contains, and what it will (probably) be able to do.

The Regulator contains the following build-in features]

[Guest]

The added ability of making

The added ability of making the board function with other ballast systems would be superb!

This will enable the use of hybrid ballast systems, controlled from a single source- very elegant.

This is especially useful for modellers who are building boats with a high freeboard.

More often than not, in these cases, it is desirable to combine a piston tank(s) used for trimming the boat in neutral or negative bouyancy, with either a vented tank/waterpump main ballast system or a compressed air main ballast system.

I'll certainly be interested if you build a batch of them.

Andy