Wireless Data transmission from 100's of Arduino's to one PC

Hi -

I, need to integrate 100's of Arduino's on Wireless - ie., will have each Arduino with HC05 - and loop 100's of these

ex: Tx of Arduino 1 is connected to Rx of Arduino 2 and Tx of Arduino 2 to Rx of Arduino 3.......n.

Data rate is just one in few seconds

Is the above configuration feasible and what could be the maximum units that could be connected?

AFAIK HC05 modules just work 1 to 1 so I don't think what you are proposing is possible.

For an application like that I suspect WiFi would make more sense using ESP8266 modules that each communicate directly with the PC.

Really you need to tell us about your project - why are there hundreds of Arduinos? Why not just a few Arduinos?

...R

100s of Arduinos - I may assume spread out over an area - what are you using them for?
What distance does the communication have to bridge?
How much data (actual numbers) per transmission, and how many transmissions overall (actual numbers)? I assume here that "Data rate is just one in few seconds" means a package of sensor data, rather than a single bit.
Data rate at one every few seconds, that's getting to 100 per second with that many devices. So it has to be fast enough to deal with the data and protocol overhead (knowing which Arduino is talking; making sure there are no collisions).

Also if you would be linking them together that means every Arduino has to process the data of all the Arduinos upstream, and send it all downstream. That can become quite a burden down the line. Serial functions are notoriously slow.

What you propose is absurd. You may get some joy by using WiFi or some other network like NRF24. Either way, it would probably be easier to have your multitude of Arduinos report to a central Arduino which sends a single data stream to PC, thereby at least confining the substantial expertise you require to one place. This last connection, to the PC, could actually be via bluetooth.

Nick_Pyner:
it would probably be easier to have your multitude of Arduinos report to a central Arduino

I have in mind that a PC (having more memory and processing power) might be a better hub for receiving WiFi from a large number of Arduinos.

I guess it would be possible to set up one Arduino as a master with an nRF24L01+ transceiver that routinely polls all the other slave Arduinos each with an nRF24 module. I am using a system like that for controlling model trains - but not with hundreds of slaves. Whether it would work with a large number of slaves depends on how much data needs to be moved.

...R
Simple nRF24L01+ Tutorial

Robin2:
I have in mind that a PC (having more memory and processing power) might be a better hub for receiving WiFi from a large number of Arduinos.

Quite likely, but also possibly a dog-chasing-car situation, while single stream of data simply gets fed into Excel - just like the more realistic datalogging projects.

I guess it would be possible to set up one Arduino as a master with an nRF24L01+ transceiver that routinely polls all the other slave Arduinos each with an nRF24 module.

Indeed. And as good a goal as any.

Hundreds of Arduinos is a hobbyist project?

I, have done many projects where in I've relayed the signal like I, specified in my requirement, but they were just limited to 4 Arduino HC05 - chain and the data logged onto serial terminal and then to CSV or on to spread sheet.

My data is 4 bytes, application is for apparel industry where 100's of sewing machines are there in a shop floor, in the event of machine breakdown - message has to be relayed to maintenance guy.

Single Wifi - can't cover an area of 100 sqmeters, we need to use many routers and link up the routers on Ethernet cable - quite complicated architecture.

It's not a hobby project but a real Industrial project.

rockwellramesha:
Single Wifi - can't cover an area of 100 sqmeters, we need to use many routers and link up the routers on Ethernet cable - quite complicated architecture.

I think your meters are way bigger than they are here... or you miss a zero or two... 100 m2 is a very small factory and easily covered by a single AP. Even large factory floors can be covered by just one or two APs as you have line of sight (mount it in the middle against the ceiling or so).

Anyway, if breakdown send message - then you don't have to send data that often. Maybe once every hour to show a site is still alive, and then whenever there's an anomaly detected.

What is it that you are actually measuring? Is it a breakdown alarm button the worker presses? Those things are important to design the overall project.

rockwellramesha:
I, have done many projects where in I've relayed the signal like I, specified in my requirement, but they were just limited to 4 Arduino HC05 - chain and the data logged onto serial terminal and then to CSV or on to spread sheet.

I'm a bit confused now.

If you know how to do that I don't understand what question you need help with?

Can you post the program from one of the Arduinos in the middle of that chain?

...R

I can see it all now! Hundreds of Arduinos watching sewing machines and hundreds more Arduinos watching the Arduinos that are watching the sewing machines, etc, etc.

Paul

Robin2:
I'm a bit confused now.

Quite possibly because it isn't true, the word "many" being indicative, and one WiFi device should cover 100 sq.m. quite nicely

Paul is partially right - 100’s of Arduino’s watching individual machines and also communicating the machine stoppage - as there is a limitation in master slave(nos) - to the communication is chained from one to the next arduino till the end of the chain - finally the data reaches to a master.

Area is 1000Sq.m - but the distance from machine is 8feets, and wireless serial communication is via HC-05, data size is 4bytes and frequency of possible data occurrence is event based, ie., when a machine stops/fails and I, assume there is no constraint on the configuration either due to data size or event occurrences.

MY question - each Arduino will have a address - so when we have 100’s of them - is there any limitation on the number of addresses we have(my thinking is there is no limitation as we are not on a network and master doesn’t poll the data in a program routine, there could be possibility that if an event occur parallelly in several machine at a same time like power failure/momentary interruptions -data loss could be there but it is not an issue here).

barcode_bihar_supiled_relay.ino (4.17 KB)

You could consider a Wireless CAN bus (for up to 120 nodes) :slight_smile:

This needs to be two way surely.

Operator presses button - red light goes on indicating message sent

Remote receiver sends reply acknowledging message

Operator sees green light go on, message has been received.

The propsal for a daisy chain of maybe 500 units all needing to be fuly working in order for one message to get through, thats just plain silly, and how would you find the failed unit.

Image from Reply #12 so we don’t have to download it. See this Image Guide

communication_config.png

…R

Why have you posted the program that is attached to Reply #12? - it seems to have nothing to do with this topic.

In Reply #9 I asked you to post a program that demonstrates the daisy-chain Bluetooth system that you said was working in Reply #7

...R

You'll need to double up your system with Arduinos that can sense when the first Arduinos fail to sense when the sewing machine fails. Then Arduinos for those Arduinos.
Don't know how any of this malarkey makes any more sense than just having the already underpaid worker, who would be unable to continue on account of a machine malf, go make a notification to maintenance.

How would an Arduino detect a jammed sewing machine anyway?

INTP:
Don't know how any of this malarkey makes any more sense than just having the already underpaid worker, who would be unable to continue on account of a machine malf, go make a notification to maintenance.

How would an Arduino detect a jammed sewing machine anyway?

I wonder if the purpose of the Arduinos is to get the underpaid workers to work harder for their pittance?

Maybe this is not a project we should assist with?

...R

Robin2:
Maybe this is not a project we should assist with?

LoL. I was wondering exactly that. The concept is absurd, I suspect the prior examples bogus, and whole thing a dastardly plot, to make the sweatshop sweatier whereby the underpaid workers don't even get any respite by putting up their hands and attracting the maintenance man's attention when the machine breaks.

Edit: No, I withdraw the "LoL"......