Durometer Hardness Sensor

I want to measure the hardness of a tissue or an object.
But I did not find a sensor, which can do.
I'm looking for something like a durometer.
thanks in advance

What physical principle do you want to use to measure hardness? The obvious one is not always the best: hardness is a very difficult quantity to measure.

For a tissue (like a Kleenex?) then you are looking at very low levels of hardness. Mostly softness, I guess. Measuring the depth of penetration under a constant force might work but making the force constant will be difficult. I'd actually look at using a small solenoid and measuring the force required for a constant distance penetration. Have it increase the drive signal to the solenoid until a specific distance has been measured with an optical or hall-effect sensor.

Could you use an accelerometer to detect the deceleration rate of a pin dropped form a know height? It would probably have to be a high frequency sensor, not one or the cheap IC's used in robots and drones.

Thanks for your answers.
I would like to measure the hardness and moisture of the skin.
For the moisture it's not a problem,but for the hardness I don't know how I can measure it.

(Morgan) I do not see any other solution, to measure the hardness, except to measure the depth penetration.
You know a sensor which can do it ?

(sdturner) it's a possibility, I can also use the deformation of piezo electric, but it's no reproducible.

Thanks (I'am sorry for my english)

What does Google say? I am sure there are sensors available at $1000 each. Work out how they work and try to duplicate the method.