Sensor to detect object by weight or pressure.

Using Arduino Sensors
1

Hi,

I want to detect when something has been placed on a table. So my idea is to put a sensor in the table and it has to detect that there is an object there using its weight or pressure.
I have seen things like Load Cell and HX711. Is there anything else we I can use? I'm looking for something very simple just that detect it, I don't need weight or anything else.
The object that has to detect weights more than 2kg and less than 15kg

Thanks
Alex

2

One of these under 2 of the table legs? How much does the table weigh?https://www.amazon.com/Qisuw-Pressure-Sensor-FSR402-Sensitive-Resistor/dp/B07F1Q2Y6K/ref=sr_1_7?ie=UTF8&qid=1541179629&sr=8-7&keywords=force+sensitive+resistor+small

3

Yeah, table is not too heavy so I guess it should work. It is also easier than HX711.
I'll take a look and investigate about connections and how to implement the code.
Thank you.

Ps: any other sensor in mind?

4

FSR will do well for the job. They're simple analog sensors, so you need an analog input and pull-up resistor for each of them. Not very accurate and even less linear but that doesn't matter for your application.

5

Is the object iron/steel ? Hall effect sensor ? Breaking light beam ? Micro switch , pressure pad ??

6

Thanks @wvmarle I will investigate them. I'm quite new on that so I might need more help in a few days :slight_smile:

@hammy is not metallic so I understand that no hall effect there. Regarding Breaking light you mean IR, I don't think I can use IR. Gonna check the micro switch solution as well https://www.instructables.com/id/Arduino-and-Micro-Switch/ something like that?
I also will investigate pressure pad.
Cheers

7

Light sensor in the table top - gets dark when the object is placed on it.

8

I don't think a light sensor works for my project. Thanks anyway for the idea, I will take into account for other projects.
I've just bought a FSR sensor but have to wait 2 weeks :frowning:

9

They're simple analog sensors, so you need an analog input and pull-up resistor for each of them. Not very accurate and even less linear but that doesn't matter for your application.

10

wvmarle:
FSR will do well for the job. They're simple analog sensors, so you need an analog input and pull-up resistor for each of them. Not very accurate and even less linear but that doesn't matter for your application.

Datumelectronics:
They're simple analog sensors, so you need an analog input and pull-up resistor for each of them. Not very accurate and even less linear but that doesn't matter for your application.

You could just have quoted my reply instead of copy/pasting it.