Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: karmax on October 13, 2008, 07:57:16 AM

Title: communication b/w underwater robot and lappy
Post by: karmax on October 13, 2008, 07:57:16 AM
hi guys... i made a autonomous underwater vehicle.i used a lappy inside it.but i am facing with a problem that when robot is inside the water then we want all the details that whts going on inside? like remote pc..... we are using team viewer software till nw. but it wants net connection. please reply any proper solution...
Title: Re: communication b/w robot and lappy
Post by: airman00 on October 13, 2008, 08:15:09 AM
hmmmm

you'd have to look for a frequency of radio that isnt absorbed by water - bluetooth for example will not work underwater
Title: Re: communication b/w robot and lappy
Post by: karmax on October 13, 2008, 09:58:04 AM
hmmmm

you'd have to look for a frequency of radio that isnt absorbed by water - bluetooth for example will not work underwater

ya u r right we thinked abt it but the prblm is we want instataneous data but through rf modules we can able to communicate serially but it cant give instatenous data
Title: Re: communication b/w robot and lappy
Post by: dunk on October 13, 2008, 10:07:48 AM
low frequency transmissions travel better through water than high.
that rules out all 2.4GHz transmissions (Wireless, Bluetooth, etc.)

you will need some sort of low frequency serial connection. unfortunately that also means low bandwidth.
try looking into RF modules that you can interface to your laptop serial port.
for 2 way comms search for a transceiver module.


dunk.
Title: Re: communication b/w robot and lappy
Post by: izua on October 13, 2008, 10:15:27 AM
Not really. Remember when they realised the maximum theoretical bandwidth of a telephone cable (for modem) is around 9600baud?
And then they started playing with phases and mixing frequencies, and got over the 57.6k.
Title: Re: communication b/w robot and lappy
Post by: karmax on October 13, 2008, 10:45:00 AM
low frequency transmissions travel better through water than high.
that rules out all 2.4GHz transmissions (Wireless, Bluetooth, etc.)

you will need some sort of low frequency serial connection. unfortunately that also means low bandwidth.
try looking into RF modules that you can interface to your laptop serial port.
for 2 way comms search for a transceiver module.


dunk.
first of all thanks for replying we also think the same and we have serial rf module also but prblm that we think that we can face is we want all instatneous data means we want to see whts going inside instatenous but if we transmit through serially then it will give some time difference and how we send all images and all....... its very hard wht u think
Title: Re: communication b/w robot and lappy
Post by: karmax on October 13, 2008, 11:26:32 AM
Hey admin! Finally what did u do to communicate wirelessly with ur fish??

Actually we need a high bit rate as we want to transmit images as well
We have been floating a wif routr ,connectd to our bot through lan, on the water surface and communicating with wifi on our side but its too much of a pain
we are looking for some simple plug and play system
ne help is appreciated
Title: Re: communication b/w underwater robot and lappy
Post by: izua on October 13, 2008, 02:26:05 PM
You can't do wifi under deep water. Water is dense, so most short-wavelength radiation is absorbed. That's why high speed wireless transmissions break while it's raining heavily.
Title: Re: communication b/w underwater robot and lappy
Post by: Admin on October 15, 2008, 09:39:39 PM
Any wireless frequency will work underwater, its just a question of range required and power of your signal. Of course, lower frequencies travel further . . .

If you place your PC side antenna in the water, that'll greatly improve reception (because signals bounce off the surface of the water).