Sensor network with Moteinos!

[jgilbert]

Hello fellow Moteino hackers.

I just wanted to share a blog post and source code at http://www.springamp.com/20131027/wireless-sensor-motetino. It describes my ongoing project to create a swarm of remote sensors using the Moteino platform.

Enjoy!

[jbeale]

Neat stuff!  I've done something like one part of that, in my case I used one light sensor looking out a window but connected to an Arduino (JeeNode) with ethernet board, uploading every minute to the thingspeak.com website. Much less powerful than a R-Pi, but very stable and reliable- worked for over a year with no maintenance whatsoever.  I also have a number of R-Pi boards now and have not had filesystem stability trouble with them (only real issue is sometimes wifi links drop out & need reboot).

I notice you powered your window watcher from a 9V battery. Probably just a quick test, but if you want longer runtime, three NiMH AA cells in series gives you about 3.6 V, enough for the Moteino, and will work about 4x longer, and you can recharge them too.  Alkaline 9V battery: 550 mAh. NiMH AA battery: 2000 mAh

[jgilbert]

Thanks Jbeale for the suggestions. I've switched the window node to a 4 pack of NiMH batteries and the runtime is indeed a lot better. Do you think I'm loosing a lot through the power regulator? Would it be better to use 3 and then skip the regulator altogether?

Much thanks,

Jeremy

[Felix]

Nice project, thanks for the writeup on your site!
Hey, remember the mailbox notifier project? I ran that since February this year it still works fine now in November, the voltage is about 5.6V. I also updated it to RFM69. So 9V is enough if you take proper low power measures.

For a window watcher I doubt you need to keep it running all the time. So you could power your LDR sensors from digital pins and only turn them on when you need a reading: wakeup Moteino, sensor ON, read sensor, sensor OFF, wake radio, transmit, sleep radio, sleep Moteino. And do that cycle like every 8 seconds or so. See my mailbox notifier project, code of how I've done that here: https://github.com/LowPowerLab/MailboxNotifier/blob/master/MailboxNotifier2_sender.ino

Don't skip the regulator, it makes sure the radio gets the right voltage, no more than 3.3V.

[KanyonKris]

Thanks Jbeale for the suggestions. I've switched the window node to a 4 pack of NiMH batteries and the runtime is indeed a lot better. Do you think I'm loosing a lot through the power regulator? Would it be better to use 3 and then skip the regulator altogether?

Standard NiMH batteries have more capacity than alkalines but suffer from a high self discharge rate (often 30% per month) so they'll be dead in less than 3 months. However, there are low self discharge NiMH batteries like Sanyo/Panasonic Eneloop that retain 75-90% of charge after one year. You may be using low self discharge NiMH batteries already, but just wanted to make everyone aware of this.

[jbeale]

a good point. I've standardized on AA Eneloops in my house starting a few years ago, and they've been working well in many different applications.

[cootcraig]

Hello fellow Moteino hackers.

I just wanted to share a blog post and source code at http://www.springamp.com/20131027/wireless-sensor-motetino. It describes my ongoing project to create a swarm of remote sensors using the Moteino platform.

Enjoy!

Thanks for sharing that, very inspiring.