My Meager Machine

[james sowell]

looks good to me .is that a pool light your cam. is in?

[Deakel]

The camera is a security camera I unplugged the IR LED's on the camera they only washed out the video and made it harder to see. And with them being disabled they don't draw energy from the batteries. The batteries (Energizer part #123 3V 4 run in series to = 12V) are external in a small waterproof box and just wired into the sealed camera housing. It runs on 12V and with a 100' tether there was to much voltage drop when running the motors and the camera would glitch out. Also this allows me to unplug the batteries to turn off the camera when not in use. So they are on board (The batteries for the camera and lights). Same setup as the lights.
The camera housing is a toilet floor drain and ring with a 6" or so piece of 3" PVC and a cap glued together and a piece of Lexan (Plexiglass) for the window. You can get that stuff at Home Depot for cheap. I cut a gasket out of gasket material got from Oriely's Auto parts and used gasket sealer on both sides of said gasket.

[Deakel]

How do the fans run right in the water? Have you tested them deep yet? I like your frame design. Its looks really good. I'm also interested in the pressure hull. Any good pictures or maybe a build sheet?

The Ducted fans are brushed motors and run great right in the water. I just run them for a min out of the water and spray a lil WD40 on em to keep them from rusting.
I'll put together some type of build design sheet and parts list as soon as i can. I haven't had the ROV out at all this year, and its hard to control without some type of variable speed control. It shoots one way or the other. I have a video in the water i'll Post in the other section under mission footage Meagar Machine. The video I'll have to edit cause its to long to post. I did see a carp that was curious about it. "Kinda Kool" I haven't tested it any deeper than about 30' down. I have a gripper arm or 3 i need to design into it also. so Arduino Mega control most likely.

[KR2_Diving]

I've got another question for you about the fans...
What is the balance like between forward and reverse thrust?

Maybe it is all the EggNog... But i LIKE these fans! I might just have to investigate these a bit further!

[Deakel]

These little fans are awsome and move the ROV really good but. They are brushed motors not brushless and they need to be turned on at the same time and at the same amount to drive it straight. One reason for analogue speed control with the ps2 controller. Brushed esc's are expensive $80 to $100 a piece and i needed 3 so the motor driver http://www.pololu.com/catalog/product/706 and http://www.pololu.com/catalog/product/707 work really well.
I looked into replacing the motors themselves with brushless motors but again the costs got pretty high for the right motor to fit (and hard to find). My first run i used relays and switches on a joystick it was impossible to turn on both switches at the same time and so the ROV was squirly and hard to get at a target position. Not sure what you mean by the balance between forward and reverse. Balance is a key issue i noticed on my ROV the weight had to be distrubed so that it sat level in the water (4 frame designs).

[KR2_Diving]

Not sure what you mean by the balance between forward and reverse.

Yea... I blame it on the eggnog! sorry!
What I meant was... does your ROV achieve the same speed if the motors are running forward, or if they are running in reverse.

In my configuration, I need to balance my thrust so that running forward or reverse, the motor creates the same power in the power in the water.

I know Steve has done lots of research on the model boat props... I was just wondering if you have ever tested this.
http://www.homebuiltrovs.com/mayfair750test.html

Thanks,
Ryan
"KR2.Diving"

[Deakel]

viewtopic.php?f=31&t=432
Here is the driveability of those ducted fans with the relay set up. I get the same speed forward or reverse. I haven't looked into the props for a couple of reasons one cause i don't wanna buy a bunch to find the right ones to use and our local hobby shop shut down so I cant go handle a few. And I haven't really been able to figure out a good way to calculate what size and pitch to use. The ducted fans seem to be just right but i have scaled the frame to fit their thrust capability. My first frame was to big and it didn't move well. Its a constant adjustment for one thing or another. The frame is going to change again, I want to be able to fit it down a ice hole for ice fishin.
By the way have you figured out how to get 100' or better outa 2 arduinos serial communication? I think i may have found the answer.
http://pskillenrules.blogspot.com/2009/ ... rs485.html

[KR2_Diving]

Pesonally i was planning on rs485. sparkfun has some nice breakout boards (link to follow). i am hoping to test just after christmas. i will keep you posted. i like the article you have posted! good break down of the process!

[Deakel]

Been a while since I've posted anything still working on the new design. Its coming together but slowly. I currently have bits and pieces of arduino code working and I'm putting the code together.
I ordered 4 new rs485 surface mount chips for converting Arduino signal to rs485 and back to rs232. The 2 arduinos are communicating through 100' of cat 5 cable full duplex. I have completed the code for the thermistor and dinsmore compass they are bottom side, transmitted top side and displayed on an lcd screen (temp and heading). Camera pan and tilt work with ps2 controller transmitting to bottom side and driving 2 servos.
I will post pics and video soon, wanna get farther along first.
Laters all
Deakel

[scubersteve]

Brushed esc's are expensive $80 to $100 a piece and i needed 3...

brushed ESCs don't have to be expensive...

http://www.ebay.com/itm/280915472461?ss ... 1439.l2649

but I don't think they will handle 12v.

I'll let you know how they work. I'm getting some for "the Guppy" project.