Seat detection

Hello,

I would like to detect if someone is on a seat (seated, standing). The seat can be in every kind of materials The goal is also to not consume so much (3 years of autonomy).

I have already do some test with piezo vibration sensor but I can only detect standing not the seating part I guess it’s because the body absorb the vibration.

My question is do you have any idea of good sensor for this project ?

Thank you for your help.

Caius.

Give us a full description of the project. We may be able to make suggestions with all the information.

What do you want to do with the sensor data?

Weedpharma

Thank you for your answer. The project is very simple :

I want to detect if someone seat on a chair or stand from it. So the sensor data must give me the information if someone has seat or stand (could be analogic or digital data, I don't care).

After receiving this information I will transmit it by zig bee to another system.

The other point is : the system must work on battery at least 3 years.

Thank you for you help.

Caius

Caius49:
but I can only detect standing not the seating part

It seems you are mixing states and transitions between states.

If you were able to detect standing-up (transition from seated to not-seated),
you would have no problem to detect seating (transition from not-seated to seated).

So I get the impression you have a sensor that claims not-seated, whether it is really taken or not.

Please clarify on what you are able to detect.

Caius49:
could be analogic or digital data, I don’t care

So you don’t care about power consumption?
I had a different impression.

A battery that will be able to monitor the seat for 3 years is not going to be small.

Weedpharma

If you were able to detect standing-up (transition from seated to not-seated)

Here I have no problem with any kind of seat

you would have no problem to detect seating (transition from not-seated to seated)

Here is the problem. It work with some seat. But with a wood bench for instance it doesn't work. I guess is due to the absorption of the vibration by the body and the bench curvature.

Please clarify on what you are able to detect.

I want to detect if someone take a seat and then leave it. I want to detect this two transition not only if the seat is taken or not.

So you don't care about power consumption?
I had a different impression.

Yes I care but for instance I have use a piezo sensor which produce energy and it could give different value proportional to the frequency of the vibration. It can also be a sensor that give me 0 or 1 if his consumption is low.

A battery that will be able to monitor the seat for 3 years is not going to be small

A smartphone battery will be enough I guess for this application for 3 years (using sleep mode and very low consumption communication module).

Thank you for your help.

Caius.

Johnny010:
https://www.pololu.com/file/download/fsr_datasheet.pdf?file_id=0J383

Thank you for your answer. I have already buy one and I wait the delivery to test it. The problem with this one is that the detection area is very small.

Thank you anyway ! :slight_smile:

Caius

Caius49:
Thank you for your answer. I have already buy one and I wait the delivery to test it. The problem with this one is that the detection area is very small.

Thank you anyway ! :slight_smile:

Caius

Sorry I deleted my post as I hadnt noticed you wanted to use zigbee! 433Mhz may be more power friendly?

Anyway, you can put the pad between the chair leg and ground :|?

Anyway, you can put the pad between the chair leg and ground :|?

Yes but not on desk chair with weel and on a bench i'm not sure that it work I will test it anyway.

I use zig bee because I have already a module but yes maybe I will swap to a solution with less consumption if needed.

Thank you.

Caius