I have been asked to design an underwater robot having pi and arduino in it . But since the bot is underwater so we are facing a problem on which communication board is best suited , we are designing the bot work at max 2 m depth , please suggest some communication board that we should use or anything else if possible .

 

I have been asked to design an underwater robot having pi and arduino in it . But since the bot is underwater so we are facing a problem on which communication board is best suited , we are designing the bot work at max 2 m depth , please suggest some communication board that we should use or anything else if possible .

Over what distance? Ultrasonic? Is cost a big factor? Sound (DTMF)? Is other wildlife going to be a problem (sharks, dolphins, whales)?

 

I guess the Navy likes sound for underwater communication. Not sure you have much bandwidth to work with however. You might be able to do 300 bits/sec with AFSK and a hydrophone.

 

You are facing a world wide problem submerge 2mtr is not the problem it's the distance.
Using low power ultra sonic does few hundred meter (15-20Khz depending salt/ temperature).
However FSK modulating is a problem echo, Doppler and distortion plus a narrow band due to things mentioned above.
All possible but it will take a lot of signal processing and I don't think that a standard board is available as yet.

 

Over what distance? Ultrasonic? Is cost a big factor? Sound (DTMF)? Is other wildlife going to be a problem (sharks, dolphins, whales)?

max 3 m distance between transmitter receiver (assume both in water ).As cheap as possible. Wildlife , not a problem.

 

max 3 m distance between transmitter receiver (assume both in water ).As cheap as possible. Wildlife , not a problem.

Wires not allowed?

 

Wires not allowed?

ok , let say wires are allowed.Then which type of communication protocol is suitable , remember i am using raspberry pi , with bot control i even want to get video data from bot camera to my handheld controller , so what should i use.

 

Tether the robot with 3 metres of data cable to a floating WiFi data link unit in buoy.

----> http://www.gizmag.com/openrov-trident-rov/39431/

 

Hello,
Please take a look on this thread : https://forum.allaboutcircuits.com/...wireless-communication-for-data-voice.138578/