need a people counting circuit...urgent. - Electronic Circuits Projects Diagrams Free

nistelrooy · 8th December 2003, 03:58 AM

i desperately need a simple/ relatively low cost people counting system to implement in my project.

Basically my PIC has to count the number of people in the room/and the temperature and adjust the speed of the fan.

There are plenty of temperature sensors i think...but i'm at a lost for a system to calculate the number of people..

it is an enclosed room with two exits.

Someone Electro · 8th December 2003, 05:43 AM

You want to caculate on temperature how meany peapole are in the room?(its imposible)

Whats not hard to do!You make weals thru peapole go wean the weal rotates it hits a switch and the pic counts(a nother weal for out).
So it can know how much peapole are in.

And you conect a temperature sensitive resistor to his alnalog input.
To the ouputs a gegulator and its finished!

Or you nead a program?

PS:
Cocodile technology can write programs(graficly)!
You can use a PIC in your simulation and run program and thean upload it to a real PIC!

**kinjalgp** · 8th December 2003, 06:29 AM

For counting number of people in the room, you need two IR-detectors and IR LED pairs attached to each door. So when the IR beam is interrupted in one sequence say Beam1 first and Beam2 second, it means that a person has entered the room. Increment the counter when this event occurs. And if its Beam2 first and Beam1 second, that means the person has left the room. This time decrement the counter.

Someone Electro · 8th December 2003, 06:51 AM

What abaot in case two are walking togeter? its just comlicated and unificent!Its usefol in outomatic garage door openers so it detects if somthing is in the door frame wean closing/opening!

**kinjalgp** · 8th December 2003, 06:58 AM

Then there is no other simple way of doing it.

nistelrooy · 8th December 2003, 02:31 PM

thanks all..

the circuit has to detect the temperature, and calculate the number of people in the room.

Say for example the temperature is X and the number of people is Y..if the said figures are deemed uncomfortable, then the fan speed will be increased.

Thats the general idea. It should weigh the number of people and the temperature against each other and adjust the speed.

someone electro..do u have a circuit of that system you mentioned, i dont really understand what you said. complete with the program? or any useful links?

Someone Electro · 8th December 2003, 04:16 PM

I didnt done anything whith PIC!

That program thing i made a "!" insted of "?".I fiksd that.

There is a simpler way to count is someone goes pas !Those rotating doors that let you go only one way(not motorised)

As for the regulator for the fan a have no idea!

Exo · 8th December 2003, 10:46 PM

Lots of ways to detect temperature with a pic
Since you want to use a 'F84, simplest way to do this (in my opinion) would be to get a I²C temperature sensor (other makes are available too). It uses a 2 wire serial bus connection to your pic.

I have to agree with the rest about counting the ppl in the room. The 2 sensor-beam idea is the simplest.

On the other hand, does it really matter how many ppl are in the room when you know the temperature? I mean, when you detect 35 degrees, you know its too hot, now mather how many ppl there are ...

nistelrooy · 9th December 2003, 02:03 AM

good point exo..

i think i've adjusted the system so that the detector will automatically shut down the fan if it detects no one in the room.

Anybody know how to interface the IR sensor or photoelectric beam with a PIC?

**kinjalgp** · 9th December 2003, 04:31 AM

You can also use DS1820 which has 1-wire interface and has accuracy of +-0.5 degree centigrade. Also it is available in extended TO-92 package which is easier to solder than SMD SOT-23 Package of TC74.
http://pdfserv.maxim-ic.com/en/ds/DS1820-DS1820S.pdf

DS1821 is same as DS1820 but has in-built digital thermostat which you can use to change your fan spped or turn it on/off when threshold temperature is reached.
http://www.maxim-ic.com/getds.cfm?ln=en&pk=2794

pebe · 9th December 2003, 06:42 AM

The build-up of CO2 in the room is just as important as temperature. This can cause the atmosphere to get very 'stuffy' and people get drowsy.

Exo · 9th December 2003, 06:59 PM

Quote:

Originally Posted by kinjalgp

Also it is available in extended TO-92 package which is easier to solder than SMD SOT-23 Package of TC74.

TC74 is available in TO220 package too.

**kinjalgp** · 10th December 2003, 03:35 AM

Quote:

Originally Posted by Exo

Quote:

Originally Posted by kinjalgp

Also it is available in extended TO-92 package which is easier to solder than SMD SOT-23 Package of TC74.

TC74 is available in TO220 package too.

Oops sorry. I didn't notice that.

nistelrooy · 16th December 2003, 04:13 AM

okay my supervisor as agreed on the IR detector method as mentioned by kingjalp.

I was adviced to purchase off the shelf products as much as i can...so where can i get my hands on 4 IR detectors which are reasonably affordable and how do i interface it with the PIC? (PIC16F84A)

vish_beatle · 16th December 2003, 03:41 PM

IR Transmitter- Detector pairs are available...you can even buy them online. Do try and get them with datasheets, or you could land up in a fix with the ckt design!

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8th December 2003, 03:58 AM	(permalink)
nistelrooy	need a people counting circuit...urgent. i desperately need a simple/ relatively low cost people counting system to implement in my project. Basically my PIC has to count the number of people in the room/and the temperature and adjust the speed of the fan. There are plenty of temperature sensors i think...but i'm at a lost for a system to calculate the number of people.. it is an enclosed room with two exits.

8th December 2003, 05:43 AM	(permalink)
Someone Electro	You want to caculate on temperature how meany peapole are in the room?(its imposible) Whats not hard to do!You make weals thru peapole go wean the weal rotates it hits a switch and the pic counts(a nother weal for out). So it can know how much peapole are in. And you conect a temperature sensitive resistor to his alnalog input. To the ouputs a gegulator and its finished! Or you nead a program? PS: Cocodile technology can write programs(graficly)! You can use a PIC in your simulation and run program and thean upload it to a real PIC!

8th December 2003, 06:29 AM	(permalink)
kinjalgp	For counting number of people in the room, you need two IR-detectors and IR LED pairs attached to each door. So when the IR beam is interrupted in one sequence say Beam1 first and Beam2 second, it means that a person has entered the room. Increment the counter when this event occurs. And if its Beam2 first and Beam1 second, that means the person has left the room. This time decrement the counter. __________________ "There is no way to peace, peace is the way!"

8th December 2003, 06:51 AM	(permalink)
Someone Electro	What abaot in case two are walking togeter? its just comlicated and unificent!Its usefol in outomatic garage door openers so it detects if somthing is in the door frame wean closing/opening!

8th December 2003, 06:58 AM	(permalink)
kinjalgp	Then there is no other simple way of doing it. __________________ "There is no way to peace, peace is the way!"

8th December 2003, 02:31 PM	(permalink)
nistelrooy	thanks all.. the circuit has to detect the temperature, and calculate the number of people in the room. Say for example the temperature is X and the number of people is Y..if the said figures are deemed uncomfortable, then the fan speed will be increased. Thats the general idea. It should weigh the number of people and the temperature against each other and adjust the speed. someone electro..do u have a circuit of that system you mentioned, i dont really understand what you said. complete with the program? or any useful links?

8th December 2003, 04:16 PM	(permalink)
Someone Electro	I didnt done anything whith PIC! That program thing i made a "!" insted of "?".I fiksd that. There is a simpler way to count is someone goes pas !Those rotating doors that let you go only one way(not motorised) As for the regulator for the fan a have no idea!

8th December 2003, 10:46 PM	(permalink)
Exo	Lots of ways to detect temperature with a pic Since you want to use a 'F84, simplest way to do this (in my opinion) would be to get a I²C temperature sensor (other makes are available too). It uses a 2 wire serial bus connection to your pic. I have to agree with the rest about counting the ppl in the room. The 2 sensor-beam idea is the simplest. On the other hand, does it really matter how many ppl are in the room when you know the temperature? I mean, when you detect 35 degrees, you know its too hot, now mather how many ppl there are ...

9th December 2003, 02:03 AM	(permalink)
nistelrooy	good point exo.. i think i've adjusted the system so that the detector will automatically shut down the fan if it detects no one in the room. Anybody know how to interface the IR sensor or photoelectric beam with a PIC?

9th December 2003, 04:31 AM	(permalink)
kinjalgp	You can also use DS1820 which has 1-wire interface and has accuracy of +-0.5 degree centigrade. Also it is available in extended TO-92 package which is easier to solder than SMD SOT-23 Package of TC74. http://pdfserv.maxim-ic.com/en/ds/DS1820-DS1820S.pdf DS1821 is same as DS1820 but has in-built digital thermostat which you can use to change your fan spped or turn it on/off when threshold temperature is reached. http://www.maxim-ic.com/getds.cfm?ln=en&pk=2794 __________________ "There is no way to peace, peace is the way!"

9th December 2003, 06:42 AM	(permalink)
pebe	The build-up of CO2 in the room is just as important as temperature. This can cause the atmosphere to get very 'stuffy' and people get drowsy.

16th December 2003, 04:13 AM	(permalink)
nistelrooy	okay my supervisor as agreed on the IR detector method as mentioned by kingjalp. I was adviced to purchase off the shelf products as much as i can...so where can i get my hands on 4 IR detectors which are reasonably affordable and how do i interface it with the PIC? (PIC16F84A)

16th December 2003, 03:41 PM	(permalink)
vish_beatle	IR Transmitter- Detector pairs are available...you can even buy them online. Do try and get them with datasheets, or you could land up in a fix with the ckt design!