Pressure distribution sensing - wireless communication

Projects General Guidance
1

Hello!

I'm planning a new project which schematic you can see on the attached picture.

The idea is quite simple:

  • ~10-12 pieces of pressure sensors wired to a NANO which collects the data

  1. In the starting version the NANO writes the data on an SD card and that's it.

  2. Second version, the NANO streams the collected data to a rapsberry Pi which is not so far (~6-7 meters) and the Rasperry visualizes it on a display (~) realtime.

I already have some questions but I would appriciate if you who have more experience in the subject can give me hints about the project.

Questions:

Any experience on these hardweres?

  • I'm planning BT connection but maybe WiFi would be better. Ideas?
  • the power consumption ot that critical, the NANO should work for max 5 hours, the Raspberry will have endless power

2

How do you plan to connect 10-12 sensors of the same type to the I2C bus?

3

Hello!

I still have to read in the I2C subject but for that purpose I've found this earlier:

https://www.aliexpress.com/item/1PCS-TCA9548A-I2C-Multiplexer-Breakout-board-for-chaining-Modules-NEW/32808950368.html?spm=2114.search0104.3.2.7oATNh&ws_ab_test=searchweb0_0,searchweb201602_5_10152_10065_5000015_10151_10344_10068_10345_10342_10343_51102_10340_10341_5130015_10609_10541_10084_10083_10304_10307_10302_5870020_5080015_10312_10059_10313_10314_10534_100031_10604_10103_10605_10594_5060015_10142_10107,searchweb201603_25,ppcSwitch_5&algo_expid=dbc2f22a-b07d-4713-8d75-9a9cafc46e25-0&algo_pvid=dbc2f22a-b07d-4713-8d75-9a9cafc46e25&rmStoreLevelAB=5

4

I believe you can connect an nRF24L01+ module to an RPi though I don't have any RPIs myself.

This Simple nRF24L01+ Tutorial may be of interest.

...R

5

Thanks Robin! Another extremely useful topic!

However I'm not sure that I need Wifi.

I'm just a newbie so maybe I'm wrong but in this case I won't need

  • high speed (I haven't calculated anything and I don't know it from guts but I feel that BT is perfectly enough for this amount of data)
  • high security (the system will be operated only by me and I won't leave it alone and nothing happens if somebody ruins a measurement session)
  • high range (maximum 10 meters is more than enough - might it be challenging with these simple BT modules like HC-05?)

So for the first version I would choose a simple BT communication (that will be challenging enogh :D:D ).

What do you think?

Yesterday I've found an ADS1115 16 bit ADC I2C compatible module what I've ordered a year ago accidentally so it came to my mind that 4 of this can handle 16 analog sensors and can communicate with the NANO on I2C. Maybe that's another doable way but as far I could find only I2C pressure sensors.

6

What is the application, that requires many closely spaced air pressure sensors and why would you expect pressure differences between them?

Perhaps there is another approach.

7

gyandras:
However I'm not sure that I need Wifi.

The nRF24 communication has nothing to do with WiFi except that it works on the same frequency band.

It has the advantage, compared to Bluetooth, that it can easily be used between a master and multiple slaves.

And even if nRF24 modules are overkill, they are very cheap.

...R