Go Down

Topic: Pressure Sensor (Read 606 times) previous topic - next topic


I am looking at creating a pressure sensor seat that is connected to a blue-tooth device/logic board which sends information to an application of whether or not there is pressure.

I came up with an idea to help in a special needs classroom that I work in. I am taking this project one step at a time. I would love to get some advice on what type of board to buy that will work with this sensor that is in the link.

Any information or tips would be great!!!



We would need the electrical characteristics of the device to determine how to help you.


Sep 14, 2018, 03:00 am Last Edit: Sep 14, 2018, 03:05 am by jremington
Please be more specific when describing
a pressure sensor seat
Is it supposed to detect when someone is sitting on it? If so, how a big a person, etc.?

The item pictured is just a switch. There are plenty of tutorials on how to use Arduino to read one.
OP's pic:


By the number of pins (2) and the stated function I would think pressure on any / some / most of those round pads will make contact and provide information to the vehicle.

I think a good place to start would be to connect an ohmmeter to one and press on different areas.  This will tell you if there are any intermediate values (with pressure only on areas of the sensor).   Or if it goes to low resistance with any pressure enough to make contact.

Please do not PM me with thread based messages.  If your thoughts are worth responding,  the group should benefit from your insight.


Sep 14, 2018, 07:36 am Last Edit: Sep 14, 2018, 07:41 am by ChrisTenone
That looks like a car seat occupancy sensor for airbag/seatbelt-light activation. It is a simple switch. If one or more of the circles has enough weight on it to close the contact, the switch is closed - that is, the two wires on the connector are shorted together. Otherwise, the switch is normally open.

To use it, connect one of the wires to ground (it doesn't matter which one), and the other wire to an Arduino pin. Assuming you have an Uno, write the following code to read it:

Code: [Select]

const byte switchPin = 2;  // connect the switch to pin 2, the other side to ground
const byte ledPin = 13;  // use the built-in LED as an indicator

void setup() {
  pinMode(switchPin, INPUT_PULLUP);
  pinMode(ledPin, OUTPUT);

void loop() {
  digitalWrite(ledPin, !digitalRead(switchPin));

You can find these switches (they come in a variety of shapes, and are about 6-10 inches across) affixed to the underside of the passenger seat in cars made in the last 5 years. It takes more than 50 pounds on the seat to close the contacts when installed.
What, I need to say something else too?


I am just curious about those little stubs at each end of the arms.  I wonder whether they might just implement a high value resistor as a sort of "tamper" or self-check test?

Go Up