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Ahoy there, I'm planning to control an arduino mega through usb connected to a pc, the problem is that it needs to be approximately 150m long, I can't use wireless because it's under sea and I don't want to mess with radio signals, there are multiple motors that need to controlled with pwm and multiple sensors that communicate through I2c and a cam (but those are on the arduino side of course)
Would a usb power hub work, if yes, would any work or should I look for a specific one?
>needs to be approximately 150m long
too long. look into rs232 conversion.
>>923579
theres a few usb over ip solutions out there, theres a linux driver for it, but you would most likely have to write the packet decoder onto the arduino, as well as a usb parser.
i know a lot of people do fiber for underwater veichles. perhapse look into that
>>923579
You could use one of these 2$ 433 MHz rf transmitter and receiver pair.
I bought a couple of these and they work great. With a proper antenna you can easily get 100m+
>>923584
Why wouldn't the usb extender work?
Would an ethernet connection work?
>rs232 conversion
Sorry but what is that?
>>923586
Care to expand on that?
>>923595
Would this work with cloudy sea for 150m? What kind of antenna are we talking about, what kind of input/input does this chip produce, will I need to manage the transmission/decode it?
>>923609
not much will penitrate 100m of water rf wise, so i wouldnt look much into that.
what do you want me to expand on? usb over ip?
also, you need to do a bit more research on this. you need to oil shield any electronics, and have good seals on everything. water can wick though wires and connectors, so having a break in your cable, like a usb extender, would eventually fail.
>>923609
>Would this work with cloudy sea for 150m?
I dont know for sure, but i suppose it wont. But dont take my word for it, because ive only used it inside my house
>What kind of antenna are we talking about
a 170 mm long piece of wire, nothing much
>what kind of input/input does this chip produce
The left chip is the receiver and the right one is the transmitter. I am uploading the datasheet/documentation about the chips
>will I need to manage the transmission/decode it?
yes you will have to use a decoder and an encoder IC to transmit digital data
These chips work on ASK, you can read about it here
>https://en.wikipedia.org/wiki/Amplitude-shift_keying
>>923621
water penitration with RF is normally bad, if anything if OP did this, he would want a yagi, not a simple wire.
also, if you are just using a wire, look into bazoka dipole antennas, super easy to build and you will get a bit more range yourself with a propper ground plane
>>923616
Yes usb over ip, if you will.
>also, you need to do a bit more research on this.
I am, the planned size is not an rc size, it's going to be quite big 1x1x1 maybe, and there's a big budget with a workshop and craftmen involved, possibly a mech Engineer, no half measures.
>>923609
>Why wouldn't the usb extender work?
Because USB 3.0 has a maximum cable length of 3 meters.
>would an ethernet connection work?
Use fiber optics if you're insistent on undersea communications.
>>923644
https://www.usbgear.com/computer_cable_details.cfm?sku=USBG-2XEXT150&cats=137&catid=137%2C140%2C120%2C199
What am I missing?
>>923645
These are shit and rarely work.
They work by boosting the data on pins 2 and 3 of the usb line. Not reliable at all.
>>923668
>These are shit and rarely work.
yeah, but you can get a proper USB-over-ethernet extender pair that has its own power supply, and chips to do the encoding/decoding of ethernet.
>>923683
What should I be looking for?
Have you considered communicating with the arduino directly over ethernet? The boards for that cost about $5 get you out to about 100 meters.
Maybe you should get an EE involved and let them bake up their own custom cable that will meet your needs?
more expensive but you could try CAN bus
FFS, this has been answered about five times already, you want to go 150m with usb? - go fiber, its the only thing gonna work.
http://www.icron.com/products/icron-brand/usb-extenders/fiber/usb-2-0-ranger-2224/
(Random example, 1st google hit, try ebay - you'd def. get a shitload of 10/100 Cat5>fiber converters cheap, but then you'd additionally need to chain USB->Cat5>fiber.)
JFI, >>923645 - 150 feet (max) ≠ 150m (its about 50m) and >>923668 is indeed correct, they are indeed shit anyway. What does work up to about 40m is chaining a few good quality 10m 'active' usb extensions or similar, they work like mini-hubs. But not for 150m, no Sir.
But otherwise, fuck around all you like, fiber the only thing actually gonna work,either reliably or even at all - run it in hosepipe or something for protection if needed, but, waterproof etc. anway. Doubt 150m fiber is especially cheap either mind, but its def. long-term cheaper than fucking around with 30 other methods that WILL NOT WORK, thank you.
>>923595
Impossible. No radio underwater. Signal is transferred underwater with ultrasound and it is unreloable because of stratification and the signal cant transfer shit.
Properly sealing anything for an excess of 15 bar is going to be hard. Machine everything well and o-rings for sealing. Some cables will react to pressure and deform, therefore fucking up the sealing at 15bar, water will seep in and its hard to debuc because it happens at the high pressure!
>>923579
Ethernet maybe will do, 150m, USB definitely not !
RS232 or other CAN bus you can try, but consider this ! If it is under water as you described you can use ultrasound it will be wireless if you didn't want to transmit video signal or gigabits of data for simply low speed communication will do.
Sound travels in water in great distances, and much faster than in air.
move PWM control to uP send just data about freq and phase. you can try to use 1 wire transmitter to cut clock signal.
>>923616Typical WiFi works at 2.4 Ghz and this freq is exactly freq of water resonation, standard microwave oven use magnetron at this freq to speedup atoms of water to raise its temp.
It simply mean the wireless will not penetrate a 1m of water, in order to be able to communicate wireless under water f.g. submarine has ULTRA LONG Distance transceivers base freq is about 3 Hz !!! receiving some text taking long time.. not suitable for remote control !
And after all they not to healthy to use !!!
https://en.wikipedia.org/wiki/Extremely_low_frequency
http://www.greatdreams.com/blog-2012/dee-blog160.html
>>923853
uh lol nvm for an arduino project it wouldn't be very good
I think matched CAN cable is $4/ft.
So you'd need nearly two grand for the cable alone
This thread... Oh boy
>>923609
>what is RS232
Learn the basics before asking stupid questions
>>923627
>water penEtration is bad
>so use a yagi
Sure, that will compensate for the 100% RF attenuation @ 433/915MHz....
>>923645
>Keeps pushing shitty half measure solution that has been shot down 3 times
>>923636
>no half measures
Okay son whatever you say
>>924040
>suggests 2.4G
Do you want to communicate or do you want to make tea?
>Hates on something that actually works
>still doesn't know a clue about it
>links some BS blog written by some crack smoking hippy thats been out in the sun for too long
>buzzwords: HAARP, mindcontrol, illuminati
>there are even old BBS bulletins on there
Thanks for the laugh guys this thread was a trainwreck
Hi OP.
I bought a set of those usb-to-ethernet dealies on aliexpress last month for $2.50 shipped.
I have them hooked up to my v-drums on the other side of the room via a 25foot ethernet cable. It works absolutely flawlessly.
However, ethernet has a maximum length of 100m, so its very unlikely that you'll get reception at that length.
>>925025
The fucking manufacturer spec on those things are 150 feet (ca. 50m) max. As has been repeatedly stated, both what runs your v-drums at 25 feet flawlessly and various other methods of cheap-shit cobbling cables together will fail at 40-50m max. As you state yourself, ether-fucking-net itself will fall over at 100m max.
OP spec was for 150m - gee, i wonder what would transmit 150m flawlessly?
>OTHER THAN FUCKING FIBER ALREADY, IN THE NAME OF FUCK.
>>925078
if you use 10mb/s speed, then ethernet on cat5 can probably do 250m. if you use coaxial cable ethernet, then you're good for about 200m with 10base2, or 500m with 10base5.
and if 56Kb/s is enough, you could use two stand-alone telephone modems, and a long telephone extension.
or if you have a budget, these guys can sell you stuff that can go a few kilometers, or even hundreds of km: https://www.perle.com/products/ethernet-extenders.shtml?gclid=COK6v4LKkcoCFQovaQodEywBNw
>>923627
>OP has muzzie name
>"big budget"
>still fuxs with arduino and USB amplifiers
>1m^3 in size and >150m in the water
Ahab, you are a terrorist plotting to attack US naval vessels or subs
>>924989
this tbq famalam
>>923890
150m of water isn't necessarily 150m straight down, for all we know he could be 20m down and 140m from the start point.
>>925334
>plots attack on submarine @ -150m
goodluckwiththat.jpeg
>>925433
That is very true. Still 20m is too much. I don't remember how much it was, a few friends of mine tried taking a phone underwater in a pocket under their drysuits. Didn't work too well...
>>925527
for GPS? - that dont work uw either..
