Building web server based I2C sensor network

Projects General Guidance
1

Hi,

In my next project I am going to use infrared-array sensor (or how Panasonic likes to call it: GridEye).
This little thermal cameras going to detect hand presence on a certain desk.

My needs are the following:
-I want to have logged data about the sensors states
(for which desk when did a hand come and when did it go away)
-I also need online realtime information for the desks
(so far what is the utlilitzation of desks, in what ratio are they used or unused)

There are eight desks. I have two basic option to choose from, but also open to other solution:

1, Buy the bare sensor (https://www.distrelec.hu/Web/WebShopImages/landscape_large/1-/01/Adafruit_3538_30129231-01.jpg) and somehow get the i2c to reach to a computer, which can process the data and do the calculations. Like using an NI USB-8451 USB DAQ device. My main problem is the length here, the biggest distance is about 20 meters.

2, Buy the evaluation kit (https://eu.industrial.panasonic.com/sites/default/pidseu/files/grideye_board.jpg)
Which has an Atmel controller embedded and can be used as an Arduino. This way the microcontroller would to the signal processing, it would decide that is is a real object or just noise. Then, an ethernet shield would be connected to the dedicated Arduino pins and via ethernet cable and a switch, the information would end up on a net server (every sensors check in and check out timestamp), so the client could provide real time charts due to usage.

I am open to any comments and I would appreciate your answers.
Thank you,
Zalan

2

I've just had a very brief look at these AMG8833 Grid Eye Sensors:

These are quite expensive ( ~$40 ) and probably overkill for simple desk occupancy monitoring, unless you are really also looking at intensity of physical activity etc., and normally a PIR sensor would do.

Anyway, the devices are interesting.

As far as connecting these together, these are I2C compatible but you can have a maximum of only 2 on a single bus because of the addressing constraint of only 2 selectable addresses (at least on the break out boards above)

I guess these are easy enough to program because you are effectively looking at an 8 * 8 matrix through I2C, but I have not looked into that in detail.

I'd suggest the following that you pair each AMG8833 device with one WLAN capable Arduino (maybe an ESP8266) and these register the detected activity to a central web server (maybe also Arduino based). ESP8266 devices can create their own WLAN so you don't need a WLAN locally unless you also need an internet connection to send the data to a remote server somewhere.