Hi all,
First post on the forums here, I was introduced to arduino back in college when using max/msp. never really got much hands on with it, but it always interested me tons.
Ive got a project that i think would cater perfectly for this, but due to me being out of the game, i'd like some more input on how to pull this off. After seeing some of you guy's projects, this should be a cakewalk!....
Here's the basis of my design:
on the Transmitter end of the wireless system i'd like to have a simple momentary switch, from there goes into a arduino system, controlled by a small battery. On the receiving end which is about 4ft away I need another arduino to activate a solenoid with these specs:
Coil Resistance at 20?C - 4.8 ?
Supply Voltage - 9-16 Vdc
so basically its just a switch controlling a soleniod ON/OFF but in a wireless package.
here are my design criteria:
-smallest footprint as possible
-as light as possible
-low battery consumption
what i DONT need:
-lots of data bandwidth (just sending a signal once every 30min)
-range ( 4ft max, no direct line of sight, but think of it like transmitter is in cabin of vehicle and receiver in under hood)
-speed (as long as it activates the solenoid within 500ms i'm fine with it, react time is not critical at all)
so after a bit of research i've looked into Bluetooth and Nordic as my best choices. I'm technically savvy but at the same time dont want to spend tons of time writing custom stuff, updating firmware, ect to get this working. Some of the Nordic stuff seems a bit un-documented, hit or miss as far as i can tell.
Another plus i've read about on the BT is that on the RN-41 Module you can put the BT into sleep/deep sleep, which will greatly decrease the power usage. This is a HUGE plus for me, as the transmitter side will be tucked away and i'd like to pull it out to recharge a battery as little as physically possible. Also briefly saw that you can ping the BT out of sleep, send its signal, then put it back to sleep, so only drawing the +-30ma during transmission, else its basically no draw. this would be AWESOME if i could do this!
So after that i'm looking towards Bluetooth, here are the parts i've come up with so far on the transmitter end, let me know if i'm missing something:
switch:
(this has an LED in it btw)
transmitter arduino:
BT board:
BT module:
battery:
I'd like this to be waterproof, so i was thinking after i load my code into the transmitter i dont need to get back into the pc->arduino port on the arduino pcb for anything since the switch is the only input i'll be using. i could put pigtails for the battery and switch coming off the arduino pcb, then epoxy pot the whole thing.
on the receiver end i can use a larger battery, or it is possible to pull a 9v source from a psu. so powering isnt as big of a concern on the receiver end. but i would still like to keep the pcb small. maybe another pro mini?
Any ideas/comments/concerns?
Thanks alot for any help guys! Looking forward to learning a lot, this is already fun!
Taylor
