ROV with SSS

[gigahertz]

Hi, I'm new to your forum, I've already learned quite a bit since I found this site and i hope to learn much more.

Back story: I'm an engineer, about a year ago I decide it would be a fun project to build an ROV (I live in S FL, lots of water). The ROV is almost complete and will get wet for the first time this weekend. It's kind of a unique (I think) design. The ROV has an on-board Dell laptop and two microcontrollers, I communicate with the ROV via another computer and a 2.4Ghz WLAN. The antenna floats and is tethered to the ROV with CAT6 cable. The ROV is also capable of surface travel like a boat.

It just recently occurred to me, what am I going to do with this thing when it's finished and the novelty of playing with it wears off? I'd like it to have some useful purpose. I came up with the idea of using it to search canals for submerged cars. The idea is to scan the canal using SSS from the surface and then submerge to visually inspect the target with the camera.

Would SSS work for this? The average canal is ~20ft deep and ~200ft wide with very still but murky water. Could I have the ROV at the surface near one side of the canal and shoot the beam at an angle into the canal? Since the water is shallow can i use a high frequency, high res set-up?

Really, I'll appreciate any advice at all, is this even feasible? I'd be willing to pay $1500 or so for equipment.

Thanks!

gigahertz

[Unregistered]

Underwater ROV

To answer your questions it would be nice to have more details like measurements, data about power supply, pics a.s.o.

Greetings from Lake-Constance

[gigahertz]

Measurements of what?

As far as power supply goes, it doesn't matter, I'll build whatever is required. I'll also take care of any wireless transmittion of data that needs to be done. I'm not concerned about the electronics part of anything, I just don't know anything about sonar. Like how well does it work in murky water? How well does it work in shallow water? How well would it work in a semi enclosed area like a canal?

I really don't want to spend $1000+ to find out it wont work.
I'll post some pics next weekend.

[gigahertz]

Thanks anyway.
I guess my request for some basic information was just too unreasonable...

[ChrisPreece]

Sidescan for the ROV

Perhaps I'm not the person to be answering this but.......firstly, I'm not sure you're going to get much for $1500. That would be the first point. There are sidescan systems available that would do a job for you.....but they pose you configuration problems.

I only have any experience with the Humminbird 900 series sidescan fishfinders....no, that should be fishing systems (that's the company line anyway), so you might like to cross check my advice with somebody else. I have a 981c, which is the bottom of the range.....I've extended the cable to 26metres and mounted it on a towfish.....it works on two different frequencies and works quite well. Certainly for the money I paid for it I'm very happy as a handful of years ago a pukka (real) sidescan was financially, way out of reach.

If you want to see what they can do....especially in calm lake or protected waterways just look at Humminbird's web site.....I was very impresssed. Over the short distances that you envisage operating your ROV the definition (especially at higher frequencies) would be very good....almost picture quality. I operate mine off the back of a boat out in the real sea and whereas a positive id is not always possible, you get a very good idea what you have found.

Higher frequencies (for a give size of transducer array) equal higher definition....but shorter range. Humminbird have a new (997) unit coming that has an option to transmit at 600kHz (mine has 262 and 455kHz) but really for the 20ft deep and 200ft wide canal you are talking about any of the older units (981 and 987 (GPS)) would be fine. The 981 might be within your budget and should cope with everything unless there is a lot of suspended debris in the water. I haven't operated mine in these conditions and do not know how it would perform....but Florida can't have murky, debris laden waterways everyday....can it?

The configuration problem comes when you want to extract data from this unit because....as far as I know....nobody has done it and there is....again, as far as I know, no provision for it. So,....you get stuck with a connective cable, which you've so far skillfully avoided!!

Any further questions then please ask!!

Chris