GPS and Analogue-In hats/boards/help!?

Discussion Raspberry Pi
1

Hi all.

I’ve previously built various GHI Gadgeteer and Pi3 based projects and also built my own mini ElectricImp PCB.

But for a one-off project I have the following requirements (it’s for monitoring the charging of 2 lead acid batteries in a camper van from a solar array)

Programmable in a sensible high level language - C#, Python
Cheap-ish - less than £75 for all parts
Two analogue inputs (range can be anything as I’ll pre-condition)
Two digital outputs (again I can add my own relay drivers)
GPS location aware
WiFi interface (I’m going to use a mobile phone WiFi access point when it’s out and about)
Able to either call into a restful web service using JSON or similar
Low-ish power, preferably has low-power mode like 50mA and then 1A or so when running

Duties:
Every few minutes check GPS position and battery voltage, log to web service
When battery voltage goes above 13.5V, set digital out to 1
When battery falls below 13V, set digital out to 0

As there is a HUGE array of GPS units and stuff, and I am kinda fed up with GHI as expensive, can anyone recommend a platform and expansion boards that will satisfy the requirements?

Again, I’m happy to wire up my own level converters, relay drivers, etc.

Thanks loads in advance! :)

2

This board came up on my radar not long ago: http://sixfab.com/product/gsmgprs-shield/

Coupled with an Automation HAT and zero W, it might fit the bill?

3

Ah yes might work quite well! Is it available yet?

4

I don’t think so, no, but not 100% sure. I think it was a Kickstarter venture so there might be more info available there in term of ETA.

5

I didn’t dig deep looking at the board, but it might be worth double checking comparability with UK ( or other) networks. It really shouldn’t be a problem nowadays, but just in case…

Gordon

6

I have gone with a Pi Zero W and the pHAT expansion board - using an old mobile phone with a £5 data SIM (GifGaf), I’ll add GPS later or put a GPS tracker app on the phone. Thx! :)