# Project feasibility

Idea:

Hello, i have been planning to work on a project that could detect human presence, plus it could also record the number of humans present in a particular area. For example the number students present in a classroom

Possible Procedure:

1- Use heat and motion detection sensors at a door, to detect if a person enters that room

2- Workable Algorithm to increment the number of humans entering the room

Limitation/Problem:

How can i decrement the number when people leave the room to maintain count?

First, you have to detect when someone leaves the target area. Then use some sort of subtraction operator.

I suggest you concentrate on the former - the latter is trivial.

You need to describe the room and door. How many entrances? Will people only be entering/exiting single file?

Put load cells under the floor and calculate the number of people based on changes in the weight.

Use a camera and image recognition software on a PC (not an Arduino).

…R

AWOL: First, you have to detect when someone leaves the target area. Then use some sort of subtraction operator.

I suggest you concentrate on the former - the latter is trivial.

I have been thinking what if i use the distance as a variable. For example if someone has entered the room its distance from the sensor at the door will increase and vice versa.

Hi, You need to detect a body. You need to detect the direction of the body. You need to only allow one body through the entrance at a time to measure the above two needs.

If you have two bodies enter the detection area, how will you know that there is more than one? How will you know their directions of travel?

You need a race, as in cattle counting.

Tom... :) PS. Sports stadiums have turnstiles.

If a mother/father is carrying two children, how do you count them?

Paul

You can measure various things like temperature, IR intensity, even sound absrobtion. And then calibrate those variables by the number of persons.

The real point is the accuracy, in my view. You can perhaps detect easily 20 person +- 5 persons. But It may be more difficult to detect 20 persons +- 1 person.

The simple way to do it is to use beacons - each student wearing one distinct beacon. But this is not fraud-proof because one student can pick 2 beacons :-))).

Alternatively, just use a trivial electronic counter based on a integrated circuit (I don't remember its code right now, but is easy to find and costs some 1 USD). Mount it at the entrance, triggered by the door itself. Not accurate, however, because one may joke and close the door repetedly...

Can the motion detector tell you whether an object is approaching or departing? How many motion detectors are you allowed?

Like robin2 has suggested, you can use Image-recognition software. What you can do is, you can capture the image and send it to processing, such as VISION API by google. It is very powerful image recognition software right now. I assume there will be some delay, since you are sending the data for processing and it takes time to process. There always trade-offs. Speed vs Accuracy.

How you will capture is something that needs thinking. There lot of hurdles in capturing image, write down all the hurdles on notepad and work you way out.

meme: you can capture the image and send it to processing, such as VISION API by google.

I presume (hope) there is a program that can do it on the OP's own PC so he is not obliged to share his data with the world :)

...R

Try make something. Not thinking, but making. In whatever way in whatever components. See how it works.

Robin2: I presume (hope) there is a program that can do it on the OP's own PC so he is not obliged to share his data with the world :)

...R

There should be. I Think he can even try a smartphone camera. Now a days smartphone cameras are smart enough to detect faces, I am not sure what is the probability of detecting.

Outside of Arduino, running OpenCV on a Raspberry Pi could be the ticket. Especially if you make everyone wear birthday hats.