Page 1 of 2

Arduino Controls

Posted: Aug 1st, 2011, 2:24 pm
by Sea-ker
Has anyone worked with the Arduina micro processor to control your ROV? I ordered one of these with the though "how hard can it be, I will figure it out" ...yeah, this is way over my head.

Has anyone had sucess with this product and is there software that is already written for it, or do I have to write my own?

Re: Arduino Controls

Posted: Aug 1st, 2011, 3:12 pm
by thegadgetguy
I'm actually working with one right now. It isn't that hard, once you get the hang of it. Were you planning to control it from the computer, or using a joystick?

Re: Arduino Controls

Posted: Aug 1st, 2011, 4:01 pm
by derelicte
Hello,

I'm also working on an arduino controlled rov right now. arduino programming is pretty easy to pick up, and there is a huge support community for it.

For my rov, the arduino will only control the speed of the three thrusters (left, right and vertical). the arduino will be on the surface and I'll run three pairs of 18/2 speaker wire down to each thruster. the rov will be controlled by a wii classic controller pro:

Image

the arduino has a library that makes reading the data from the wii controller trivial.

the speed for each thruster will be controller by three pololu motor controllers:

Image
http://www.pololu.com/catalog/product/705

I don't plan on sending video back up to the surface or using a computer to control it. the arduino gives me more precise motor control (variable speed instead of off/on) and can interface with a hand held controller without the need for a computer.

please ask if you have any more questions about using an arduino.

Re: Arduino Controls

Posted: Aug 1st, 2011, 6:15 pm
by Sea-ker
I had previoulsy thought that if you use the Arduino then you must use a computer to control it but I would rather use a controler or joystick. I think that my bigest problem is getting started, I have downloaded the software off of thier website but I am not really sure where to go from there.

I would really only need 3 speed controls to control my ROV since I am using a duel rear thruster and turning will be done using positive or negitive forward thrust. I am hoping to combat some boyancy issues by using 2 thrusters together for up and down so that even if I get close to nuetral boyancy, I can still control depth using thrust.

I will be sending video up from the ROV but that will all work outside of the Arduino.

Re: Arduino Controls

Posted: Aug 1st, 2011, 7:09 pm
by thegadgetguy
Varying motor speed is quite easy when the input is from an analog joystick. If you had two joysticks, one for each thumb, you could drive your ROV like a tank, with one joystick for each forward thruster. Will you be using motor controllers, MOSFETS, or some other form of motor control? Also, will the arduino be on the shore, or on the ROV.

Re: Arduino Controls

Posted: Aug 2nd, 2011, 7:04 am
by Sea-ker
I currently have my ROV working using 3 switches that are just on/off (right and left thrust and vertical thrust). What I would like is to be able to control the speed of the vertical thrust, right and left speed control would be nice but not necessary. I thought that this would be easier using the Arduino, and I plan to use this eventually once i learn how to program it but for now if I could use a analog controller of some type to control motor speed, that would get me by until I have the Arduino all worked out.

My problem it going to be that i used a 14 GA extension cord to send power to my ROV, I used the diagram provided on this site to build 3 small circuit boards with DPDT relays that power the motors and use a RJ45 network cable to run the controls to the relays. Therefore, I assume I will need to put the speed control units down by the relays in the ROV. What kind of speed control/topside control would be recommended?

When I use the Arduino, I will probably put it on the ROV so I just have to send 1 power/grnd and a control wire.

Re: Arduino Controls

Posted: Aug 2nd, 2011, 10:46 am
by derelicte
if you don't want to change your tether, then the obvious location for the arduino would be in the rov.

I plan on using the left analog stick for forward/backwards/left/right and the right stick for the vertical thruster, I am also planning on using the thrusters to "trim" the buoyancy of the rov.

the wii controller is a little funny as the left stick has twice the resolution as the right. we'll see how it works out to drive with these stick assignments.

Re: Arduino Controls

Posted: Aug 2nd, 2011, 5:31 pm
by thegadgetguy
What type of controller are you going to be using? Do you want to stick with your switch arrangment, but have, say, a potentiometer controlling the up/down thruster?

For actual speed control, you could use a motor controller to control the speed. There are other options, too, if you don't want to do that.

Re: Arduino Controls

Posted: Aug 6th, 2011, 9:43 am
by Sea-ker
Actually, I would like to use a motor controller for now. I went to my local hobby shop and they have ESCs, but they only have ones that work over RC, nothing that is direct wired. If I get a motor controller like an ESC, what do I need to use topside to control the speed of the motor?

Re: Arduino Controls

Posted: Aug 6th, 2011, 2:21 pm
by derelicte
an arduino can control a rc esc very easily. there are libraries that handle all the work. all you would need is a joystick or two.

http://arduino.cc/en/Reference/Servo