atulkatti
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Connecting spread out sensors wirelessly

Sat Oct 20, 2018 4:09 am

Hi all
I am planning a couple of projects in agriculture and shop floor where the sensors (Accelerometer, humidity , temperature) are spread out over a distance. I have one rasperry pi. How can i connect the sensors to Rpi wirelessly. I am thinking of Zigbee and Bluetooth. Can someone provide detailed info on this. Using wires to connect may be a messier approach.

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OutoftheBOTS
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Re: Connecting spread out sensors wirelessly

Sat Oct 20, 2018 9:29 pm

Most people use ESP8266 as nodes on each sensor then send the data back to the RPi via MQTT as a client and run a MQTT broker on the RPi

Here's a bit of a tutorial from Adafruit https://learn.adafruit.com/diy-esp8266- ... spberry-pi

baetis
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Re: Connecting spread out sensors wirelessly

Sat Oct 20, 2018 9:50 pm

I agree - the modules can be bought on ebay for $3-5, use very little power (9v battery could last months) and are small pretty easily hooked up to i2c, spi, rs232.....
I'ld rather weather proof an esp8266 compared to a RPi.

PhatFil
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Joined: Thu Apr 13, 2017 3:55 pm

Re: Connecting spread out sensors wirelessly

Sat Oct 20, 2018 9:55 pm

for esp825/6 and esp32 devices both off the shelf and diy check out tasmota firmware https://github.com/arendst/Sonoff-Tasmota/wiki

you should be able to source bluetooth ble sensors that broadcast/advertise information your pi can 'crack'
https://zsiti.eu/xiaomi-mijia-hygrother ... pberry-pi/
https://github.com/ThomDietrich/miflora-mqtt-daemon
for example..

atulkatti
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Joined: Sat Oct 20, 2018 3:18 am

Re: Connecting spread out sensors wirelessly

Sun Oct 21, 2018 6:35 am

Thank You experts...Im assuming we dont need wifi to transmit data from ESP8266 to Rpi. Getting a wifi in the field will be a problem.

B.Goode
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Re: Connecting spread out sensors wirelessly

Sun Oct 21, 2018 6:44 am

atulkatti wrote:
Sun Oct 21, 2018 6:35 am
Thank You experts...Im assuming we dont need wifi to transmit data from ESP8266 to Rpi. Getting a wifi in the field will be a problem.


I thought the main point of an esp8266 was that it enabled WiFi communication. If you don't want to use that facility maybe an esp8266 is not an optimum choice? What alternative form of communication do you plan to use?


If you have an RPi (either with built--in WiFi, or an external dongle) then you can have WiFi access 'in the field.' https://www.raspberrypi.org/documentati ... s-point.md

atulkatti
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Joined: Sat Oct 20, 2018 3:18 am

Re: Connecting spread out sensors wirelessly

Sun Oct 21, 2018 6:52 am

I have Rpi 3B+ which is wifi enabled like the ESP....But finding a WLAN network in the field could be difficult. If there is bluetooth module per sensor i can stream this data to Rpi and then get the data out via a long Network cable to the modem located several meters away

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DougieLawson
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Re: Connecting spread out sensors wirelessly

Sun Oct 21, 2018 10:28 am

atulkatti wrote:
Sun Oct 21, 2018 6:52 am
I have Rpi 3B+ which is wifi enabled like the ESP....But finding a WLAN network in the field could be difficult. If there is bluetooth module per sensor i can stream this data to Rpi and then get the data out via a long Network cable to the modem located several meters away
Make your RPi run as the access point. Your ESP8266 (aka Wemos) based sensors can then connect to it wirelessly.
https://www.raspberrypi.org/documentati ... s-point.md
Microprocessor, Raspberry Pi & Arduino Hacker
Mainframe database troubleshooter
MQTT Evangelist
Twitter: @DougieLawson

2012-18: 1B*5, 2B*2, B+, A+, Z, ZW, 3Bs*3, 3B+

Any DMs sent on Twitter will be answered next month.

atulkatti
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Joined: Sat Oct 20, 2018 3:18 am

Re: Connecting spread out sensors wirelessly

Sun Oct 21, 2018 2:30 pm

DougieLawson wrote:
Sun Oct 21, 2018 10:28 am
atulkatti wrote:
Sun Oct 21, 2018 6:52 am
I have Rpi 3B+ which is wifi enabled like the ESP....But finding a WLAN network in the field could be difficult. If there is bluetooth module per sensor i can stream this data to Rpi and then get the data out via a long Network cable to the modem located several meters away
Make your RPi run as the access point. Your ESP8266 (aka Wemos) based sensors can then connect to it wirelessly.
https://www.raspberrypi.org/documentati ... s-point.md
Thanks

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