Cost to Build This?

Hey Guys,

I'd like to first thank whoever decides to read this. I sincerely appreciate it. I really do. If our shoes were swapped I would do the same for you. Anyways, I just want to make clear that the respect is there and the thanks is there for any advice given.

I'm wondering if anyone could give me a basic estimate of the cheapest that this could me made for. I'll give you all the details as it really comes down to this, but if i'm missing anything please let me know.

  1. Microcontroller of some sort, that simply monitors a digital sensor connected to it. No fancy analog signals just a simple on or off.
  2. When the microcontroller detects a rising edge or 1 from the sensor, it passes this data to the web... (Welp. I assume this will be where it becomes impossible to do it inexpensively.)
  3. This needs to be powered by solar since the device is outside at all times....

As far as the sensor cost, it is a very basic sensor so just take that completely out of the equation. Could this be built(microcontroller included) with $50 or is that unrealistic?

Guys. Again, thank you to anyone who takes the time to read this and reply.

  • QuestionAsker

Microcontroller: Arduino Uno from Amazon for about 6-9 dollars or Arduino Nano for about 7$

Web connection: Ethernet Shield on Amazon for roughly 8$

Solar: Small solar panel on Amazon for about 8$ or so.

(This is roughly the cheapest you could get these)

Total Cost: Around $23-25

You could use an ESP8266 (ESP-01) as processor and WiFi as connection (if possible) for 1.50€.

QuestionAsker:
2. When the microcontroller detects a rising edge or 1 from the sensor, it passes this data to the web... (Welp. I assume this will be where it becomes impossible to do it inexpensively.)
3. This needs to be powered by solar since the device is outside at all times....

$50 or is that unrealistic?

I don't think $50 is too unrealistic, but a lot of the cost depends on whether what you are doing is serious or frivolous.

If you are running on solar you might find a few nasty surprises if you just hook a Uno to a cheapo solar panel, indeed it is very likely. You need to look into low power operations, and choose your components carefully. I don't know about the Nano but it is almost certainly a better bet. You also need to look at battery backup, and charging of same. You may find that you are better off not using an Arduino at all, but getting an ESP8266 module instead, as it is specifically designed to do the sort of job you have in mind. It costs about $5 and I believe it has very low power consumption.

One important piece of the puzzle nobody has mentioned is distance - it sounds like (with the solar) it is some sort of stand alone gadget monitoring something and it needs to connect to the "web" - what kind of distance are we talking about here? Is this something up on a mountain or something somewhere that needs to communicate across several miles or is it something 50 feet away from the nearest wifi access ?

@SMM2, @Whandall, @Nick_Pyner and @GPSMikey.

Just wanted to thank each of you for taking the time to read this and reply. You guys are awesome.

I have some stuff going on right now, but i'll reply back to each of you within an hour or two with some more information with respect to your posts.

Again, you guys rock. I sincerely appreciate you sharing your knowledge with me. I'll get back to you guys in roughly 2 hours with some more information.

Cheers all.

SMM2:
Microcontroller: Arduino Uno from Amazon for about 6-9 dollars or Arduino Nano for about 7$

Web connection: Ethernet Shield on Amazon for roughly 8$

Solar: Small solar panel on Amazon for about 8$ or so.

(This is roughly the cheapest you could get these)

Total Cost: Around $23-25

Whandall:
You could use an ESP8266 (ESP-01) as processor and WiFi as connection (if possible) for 1.50€.

Nick_Pyner:
I don't think $50 is too unrealistic, but a lot of the cost depends on whether what you are doing is serious or frivolous.

If you are running on solar you might find a few nasty surprises if you just hook a Uno to a cheapo solar panel, indeed it is very likely. You need to look into low power operations, and choose your components carefully. I don't know about the Nano but it is almost certainly a better bet. You also need to look at battery backup, and charging of same. You may find that you are better off not using an Arduino at all, but getting an ESP8266 module instead, as it is specifically designed to do the sort of job you have in mind. It costs about $5 and I believe it has very low power consumption.

gpsmikey:
One important piece of the puzzle nobody has mentioned is distance - it sounds like (with the solar) it is some sort of stand alone gadget monitoring something and it needs to connect to the "web" - what kind of distance are we talking about here? Is this something up on a mountain or something somewhere that needs to communicate across several miles or is it something 50 feet away from the nearest wifi access ?

Thanks a lot guys for the reply. The ESP8266 would be ideal, and this is the first time i've heard of it, completely surprised at the cost, but the problem is im looking to somehow do this without a Wifi connection... and I'm unsure how this would work and assume this is where it gets very expensive. (i.e over the $50 or $100 range)

@GPSMikey. You have it right, stand alone gadget monitoring something and needs to be connected to the web. It won't be up on a mountain but in a city. The closest wifi access would be miles away.... so I don't think that's a possibility unfortunately. Is it possible to move the data via SMS?

Consider this, there will be many of these devices scattered throughout an area, miles away from the other if that helps in anyway. Is it possible to relay data from one device to another, in sort of a chain fashion by radio... like XBee.... until it reaches one final point that has wifi access and can upload this data? This is me just talking out of my ass here, I assume what I just said is completely impossible.

But yes, the additional information I need to add is that there is really no wifi access nearby, however there would be multiple of these devices scattered throughout the city if that can somehow be leveraged through radio relaying of some sort.

Cheers guys. I appreciate it.

Whandall:
You could use an ESP8266 (ESP-01) as processor and WiFi as connection (if possible) for 1.50€.

the $1.50 for the ESP8266 sound a but on the cheap side. I was thinking $2.00
an enclosure

figure $10 for the solar panel, a 8,000 mah battery pack in a 5v package for cell phone charging.

I think if you figure $20,00 for the project, you could get it done.

now, how often do you need to send the signal,
does the sensor need power ?
how far away is your wifi ?

if you say it is on the far side of the ranch, 4 miles down the road… well, this will not work.

But yes, the additional information I need to add is that there is really no wifi access nearby, however there would be multiple of these devices scattered throughout the city if that can somehow be leveraged through radio relaying of some sort.

if you are in a city, you have wifi.

distance is key.
do they have to be wireless ?
if you have one withing range of another, there is no reason you cannot have them talk and exchange data.
just having one near a Starbucks and you have free wifi.

dave-in-nj:
the $1.50 for the ESP8266 sound a but on the cheap side. I was thinking $2.00
an enclosure

figure $10 for the solar panel, a 8,000 mah battery pack in a 5v package for cell phone charging.

I think if you figure $20,00 for the project, you could get it done.

now, how often do you need to send the signal,
does the sensor need power ?
how far away is your wifi ?

if you say it is on the far side of the ranch, 4 miles down the road.... well, this will not work.

dave-in-nj:
if you are in a city, you have wifi.

distance is key.
do they have to be wireless ?
if you have one withing range of another, there is no reason you cannot have them talk and exchange data.
just having one near a Starbucks and you have free wifi.

Hey dave-in-nj.

Thanks for the reply back. The signal wouldn't be sent often. It wouldn't be sent at all during night and morning. Very rarely to be honest. And the sensor would need power however I don't think it would need much at all

I am in a city, however, sadly.... where these devices will be I will not have access to any wifi. So that is definitely out of the question.

When you say there is no reason not to have them talk to eachother and exchange data if they are within range. Could this be done with something like a XBee? I would have a access to wifi somewhere, and could have a device there to receive data from a chain of sorts of transmissions if this is doable?

Thanks again Dave.

It sounds like you need a GPRS shield. At least, by being in the city, you have a mobile phone network. These shields are not famous for low power consumption. This is not a problem with short occasional bursts but what it means is that a battery will be doing the real work, and the solar panel is just there to charge it in the downtime. Once you have GPRS, I don't see the point of using WiFi, or any other wireless, for anything.

Nick_Pyner:
It sounds like you need a GPRS shield. At least, by being in the city, you have a mobile phone network. These shields are not famous for low power consumption. This is not a problem with short occasional bursts but what it means is that a battery will be doing the real work, and the solar panel is just there to charge it in the downtime. Once you have GPRS, I don't see the point of using WiFi, or any other wireless, for anything.

I agree. GPRS would do the job but I'm trying to keep the costs down and I assume a GPRS shield would at least cost me $50.

If there are multiple devices scattered around a city doing the same job, reading a sensor every now and then, is it possible to somehow relay information to eachother in a chain of sorts by radio, and then finally to a sort of hub device that has a GPRS shield or wifi access?

Thanks Nick

May I throw a bit of cold water on this enthusiasm for low cost?

What happens if you go the low cost route and YOU can't make it work?

The people giving advice are experienced and they know how to debug things if they don't work as first expected. And they have a huge amount of background knowledge to help them get it working in the first place.

Microcontroller projects are never quite as straightforward as building a Lego model.

Solar / battery systems can also be tricky. It is difficult to forecast their performance.

If you lack experience, or if you are not patient and don't have lots of time to spare, or if you are not enthusiastic about learning Arduinos, I suggest you focus on finding a solution that YOU (not me) can implement and make cost a secondary consideration.

...R

It much depends how often you collect data and how quickly you need to upload them. If you can afford to store data in a buffer and send them all at once every hour (or even day) GPRS would be good choice. You can have it off most of the time and turn it on only for data transmission. If you need upload the data ASAP and the trigger comes every few seconds it may be problem - I don't have idea how much a GPRS can eat but you will need good energy source.
You need to think about the sun. How long and how often need the device to work without it? How short is a day in winter? How often is cloudy and raining? What about snow/dust on the panel? And last but not least: what will thieves think about your nice shiny solar panel? All of this will greatly affect your cost from a few bucks to a few hundreds or even make it near-impossible.
If you somehow manage to get it really low power look here for interesting project - you may start with something similar.
Also look here for some low-power hints.
Basicly you may assume MCU cost will be neligible, I think a form of GPRS with own SIM card for each device will be needed (I have no idea how much this may cost) and power source cost depends on your needs.

QuestionAsker:
I agree. GPRS would do the job but I'm trying to keep the costs down and I assume a GPRS shield would at least cost me $50.

$AU27.99

If there are multiple devices scattered around a city doing the same job, reading a sensor every now and then, is it possible to somehow relay information to eachother in a chain of sorts by radio, and then finally to a sort of hub device that has a GPRS shield or wifi access?

Probably not, unless the city is in Lilliput and you are prepared to spend up a lot more than you seem to be.

GPRS GSM SMS GPRS € 2.86 free shipping.

I thought about your project. What do you want to manage? It looks like you want to make many of those devices. For $50 each? It doesn't look like hobby project. But still it looks very interesting.
If you used GPRS you would need a SIM card for each one. It may be quite expensive for upkeep. Maybe you should think about WiFi anyway. Are you free to place them anywhere you want? You could place them somewhere close to a free hotspot. Or you can ask someone to share their WiFi for "greater good" - you won't stream much data.
You could also use some RF connection to make a web of your devices. But how close to each other will they be? You will need great redundancy - what will happen if one device got damaged or stuck due to a bug? Which connection to use? WiFi has short range, many frequencies are not legal to use without some license. Has Arduino memory large enough to solve all of this?

Robin2:
May I throw a bit of cold water on this enthusiasm for low cost?

What happens if you go the low cost route and YOU can't make it work?

The people giving advice are experienced and they know how to debug things if they don't work as first expected. And they have a huge amount of background knowledge to help them get it working in the first place.

Microcontroller projects are never quite as straightforward as building a Lego model.

Solar / battery systems can also be tricky. It is difficult to forecast their performance.

If you lack experience, or if you are not patient and don't have lots of time to spare, or if you are not enthusiastic about learning Arduinos, I suggest you focus on finding a solution that YOU (not me) can implement and make cost a secondary consideration.

...R

I hear you Robin. I am patient and I have the time to spare so it's not a problem for me.

Whandall:
GPRS GSM SMS GPRS € 2.86 free shipping.

That's surprising. Is that price too good to be true? This comes with someone from no experience of course. Should I just assume that's some sort of scam or is that a common price? Amazing if that is the case.

Thanks for the link Whandall.

Smajdalf:
I thought about your project. What do you want to manage? It looks like you want to make many of those devices. For $50 each? It doesn't look like hobby project. But still it looks very interesting.
If you used GPRS you would need a SIM card for each one. It may be quite expensive for upkeep. Maybe you should think about WiFi anyway. Are you free to place them anywhere you want? You could place them somewhere close to a free hotspot. Or you can ask someone to share their WiFi for "greater good" - you won't stream much data.
You could also use some RF connection to make a web of your devices. But how close to each other will they be? You will need great redundancy - what will happen if one device got damaged or stuck due to a bug? Which connection to use? WiFi has short range, many frequencies are not legal to use without some license. Has Arduino memory large enough to solve all of this?

Cheers Smajdalf. That's for giving it some thought. There would probably be at minimum 50 of these scattered probably 20 miles from eachother, so i'm trying to keep the price is low as possible otherwise it isn't feasible. What is the typical price per SIM card from your experience?

Unfortunately they need to be placed in specific places. However, you did give me the idea of looking into free hotspot zones and if there are any in that area. But highly unlikely.

They would be probably 20 miles away from eachother on average. Please, tell me more about using a RF connection to make a web of my devices? This sounds interesting. Possibly using LoRa?

Yes I agree, redundancy will definitely be an issue but at the moment I'm just curious of how low cost this can be assembled for while ignoring redundancy for now.

Thanks a lot Smajdalf.

Bump. Cheers all.

Guys, again, thank you so much for the replies up to this point. I've learned so much from you already. Feels good.

(Bump)