Hi to all,
at the moment, i'm using four I2C sonar sensors connected on my Arduino Mega and they are working great.
(I'm using four SRF08 sonars from devantech)
The problem is that I need to use waterproof sonars but i'm not able to find any isolated sonar which use I2C.
For example, I've found SRF485WPR but it uses sr485 serial communication; i've found also some sensors from Maxbotix but they use rs232.
It is possible to find somne waterproof sonars which use I2C communication?
It would be better for me because I've already wrote all the Arduino code to manage I2C devices and i'd like to avoid to re-write everything in order to use rs232 or rs485.
Moreover, i do not know how to interface and connect multiple sensors in order to use them with rs232 or rs485.
Can you tell me if it is possible to find any I2C waterproof sonars?
Thank you to all.
Have you considered making your existing sensors water-proof? I think instructables.com have several stories about how to waterproof things.
What is waterproof for you? an occasional drop, rain, or under water?
To start with the last, the speed of sound will be quite different under water and the last time I looked the SRF08 Ultra sonic range finder was meant to be used in open air.
Also in a rainshower the speed of sound will change as the humidity of the air affects it.
I do not know how to make the sensors waterproof and i do not know if they would be reliable.
I have to use them on a rover which has to move on the beach where there is a lot of sand.
It does not have to move on the water, but i think the sand can be dangerous if there is wind.
So it does not go under water but as the sea is nearby and your rover can be catched by some wave it must be pretty watertight.
Problem is that when waterproofed the (ultra)sound might be blocked. Think I would go for a tight wrap in plastic foil, only one layer and test if the sensor still works, anyway I expect that you at least need some recalibration of the distance formula with the foil in between.
Please check - www.instructables.com - and search for waterproof there, many examples.
Hope this helps,
I searched on that site and there are some good example on how protect the sensor, thank you a lot for the input.
The problem is that the solutions suggested on the site does not seem to be reliable; it would be better to use a sonar which is already isolated.
The SRF485WPR which I tested is really good but it doesn't work on I2C bus.
I looked on the net but i found no other isolated sonar which use I2C bus: may be it is not possible to use I2C bus on waterproof technology? It seems very strange to me.
I2C technology comes from devices where IC's needed to communicate (Philips TV market /medical devices IIRC), typically distances shorter than 1 meter.
It is allways possible to let an Arduino act as I2C client and have it control the Sonar, but that would be quite overkill and a great increase in price... don't know if cheap I2C(slave)-UART bridges exist.