Bot Cousteau- My ROV project

[a_shorething]

I know it's a corny name. My son came up with it and I think it's awesome though!

Hey everyone. Been lurking here for a while and I love the site. I've been bitten by the ROV bug and I'm working through some initial tests and design options now.

I'm a C# programmer and a tinkerer.

My plan is to work out the control and communication issues first, then build the actual ROV around whatever seems to work best.

Step one was to work out a way to control it and I thought an XBOX controller would be a cool way to do it so I found the SDK for XNA and hacked it.

Then I wrote a C# interface that would show what was going on and gave a user some feedback and tested my serial comm to an Arduino UNO with a Motorshield from Adafruit.

Here's version 1.0 of the interface: What do you think? (I know it looks similar to some other stuff that's out there, but it's all my own code and there are only so many things you can do with the publicly available XNA base classes).


I built it so it can be used by anyone who wants to use it for a car, UAV or ROV or whatever. I called it XBOX pass-thru because it just hooks up and works. You set the baud rate and com port and it saves it for next time. You start it up and it starts communicating, no muss no fuss. I can pass along the Arduino sketch code that handles the serial codes on the outside. I can imagine some kinds of code that are used like toggles and volume controls (A button increases light 5% B button reduces it...), others like a 'trim' setting to add power to left rudder to offset a slight current or maintain depth...

Oh, and also, it's set up to handle up to 4 controller inputs so you can have a 'pilot' and 'co-pilot' or someone can work a camera or grabber separately.

Now that I've got the serial comm ironed out, I'm going to see if I can get an IP camera connected and working down there.

My plan is to use one CAT-5 cable to use two independent lines of full-duplex Ethernet comm. I found that I can use one cable if I put a splitter at one end and a joiner at the other with a switch or router, so that's my plan. I found a cheap switch for $14 shipped and I have some Cat-5 to test it with. The camera will be here Friday so that's phase 2.

I'll update as things move along in case anyone is interested.

Thanks in advance for any comments or advice.

[fireslayer26]

Looks great so far! I'll be keeping an eye on this thread.

[a_shorething]

Thanks for checking in!

One interesting thing to note: I spent several days trying to get my serial communications as thin as possible. I devised this really compact code system to send every command in 3 bytes or less, it was really very clever. In practice I couldn't get the damned thing to talk for more than a few minutes without it getting bunged up somewhere though.

My initial tests had been a breeze just sending ascii characters and parsing it out in the Arduino sketch so I went back to that and tried it again, great speed, no apparent data loss.

Next test will include transferring data back to the PC for more than just signal acknowledgements (controller vibration as a warning might be cool).

Once I get all of the code back into the sketch I'll be ready to test the IP camera functions on Friday. That should be really cool.

Also (random thought) I was originally thinking of including a browser window in the interface, but then I thought: Why do that and limit the size of the window when I can just open a regular browser window and size it however I want with my control panel running in the background or on the side?

[rossrov]

Welcome, a_shorething. Good to see some more working computer control stuff on the forum. My view: All "hobby" ROVs, excluding the very simplest already have layers of high-tech, like brushless speed controllers, microcontrollers and modified RC gear, so adding in a computer and IP camera does not add a real lot to the existing complexity and non-repairabilty of the above. Looks like you are pretty close to getting a full control and video/data acquisition system running. If you intend sharing it then this I think many hobbyists will use.
Just a suggestion about your thoughts on using a browser window alongside your control. Have you considered using an IP cam viewer or something like this http://www.videolan.org/vlc/index.html rather than a browser? I am using a browser at this point because it was relatively easy to do. It works OK but is overkill for just displaying video and sending/receiving a few bytes of data. Also, by getting rid of the browser you would get away from cross-browser compatibility issues.

[a_shorething]

Hey Ross,

Thanks for the reply.

Mostly I wanted to use a full browser for the camera functions and because I didn't want a small window. I got the IP camera today and it looks pretty cool. Unfortunately right now it ONLY works in IE and it loses some functionality in any other browser. Video is still there, but the camera has PTZ and some other features like snapping a picture, adjusting contrast and which resolution setting you want to use. None of that seems to work in any browser but IE, let alone in a straight viewer. I may have to write my own stuff for this too, not sure (found an SDK but it's a laughably bad translation from Chinese so it will take some doing).

The Laptop>Ethernet switch>camera works perfectly even though there is a little lag at the highest resolution setting. Tomorrow I'll get the splitter/combiners and wire up an Arduino with an Ethernet shield to see how that works. The interface shown here is a direct USB connection using Serial. I'm curious how it will work with an Ethernet switch in the middle. The bandwidth is higher, so I'm hoping there will be no ill effects from packetizing things.

I'm glad to hear you say you think others might be interested in this kind of interface. I was actually thinking of making the sketches available for free but maybe asking people to kick in a few bucks if they want a copy of the pass-thru part to help me fund my projects. I tested it with a wireless XBOX USB hub today and it works perfectly. It's coming out pretty nicely if I do say so myself.

If anyone out there wants to help me beta test the XBOX pass-thru I'd be willing to pass along a free copy or two in exchange for some feedback...

[a_shorething]

In case anyone is interested. I shot a short vid showing the 'XBOX pass thru' program I wrote and how it controls motors.

Here it is:

[a_shorething]

So I figured out the SDK for my camera: A Tenvis IPRobot 3 IP camera. The documentation was, well, let's just say it was a good guide, but left a bit to be desired.

Not all of the codes matched up and some did nothing, but once I understood the syntax I just fired random codes at it until I got the pan and tilt to work the way I wanted.

Then I mapped it to my XBOX 360 controller for complete camera control using the DPAD buttons (up/down/left/right on the left thumb). That leaves plenty of control functions for the rest of the buttons and it's pretty intuitive.

I think I'm going to see if I can get the 'camera description' field to update dynamically and if so, then I'll have a way to send (and record for later) the signals from the Arduino board like depth, compass heading and whatever else I want to add. By updating the camera description dynamically on a regular basis, it will appear to be scrolling through all of my data. Actually I might hook up a button on the controller to scroll through them in order so I can select what I want displayed at any time I want it.

I heard from Ole on here asking about the software. I'm excited to work with him on development of a complete system. He's coming at it from the hardware side first, and I'm starting with the com/software/firmware side. Hopefully we'll meet in the middle with a usable system. I'll post when I make more progress.

[a_shorething]

Hey everyone, took a break from the interface to do some cool hardware work.

I'm designing a mag coupling for a thruster system that will allow you to just plug in a bilge pump and use it to drive a sealed unit from inside a 3" PVC pipe.

I didn't realize it but my 3D printer had been just a bit out of calibration and it was bothering me. (was doing small prints OK but large ones always seemed to have some imperfection or 'shift' at one point). It was inconsistent and I could never catch it doing anything wrong until the other day. Since I fixed that issues it's been great (problem was with it feeding filament crooked when it got up too high off of the heated bed). So now I've been able to do several iterations of my design in the past week.

By tonight I should be able to do a proof of concept just to see if it will turn the thruster blade on the outside of the PVC. If it does that OK, then I'll post up some pics and if anyone wants to help me finish up the design for anyone to use, that would be great. I'll need to do a water test, thrust test and I guess a sea trial.

I plan to make the .stl files available for anyone to share/modify/whatever once it's done (if it works). So far the results are encouraging and it looks pretty cool too!

[Under_The_Surface]

hey
how is it possible for me to download that program from anywhere?

[a_shorething]

Hi,

Thanks for your interest.

Send me a PM with your e-mail address or e-mail me at m.r.frye at comcast.net and I'll send it to you. It's not available for download yet, as it's only in beta.
Mike