How can I measure the thickness of a sheet made up of any material and apply the same mechanism to measure the thickness of a hollow container
Is there something that would work for any material? but in real life would want to measure thickness of metal and non metal primarily plastic, copper, mud/clay sheets. These 3 primarily.
Is there a way to make it portable? Only software or mobile based?
Mechanical measurement, such as those digital calipers, is the only way that would work for any solid material.
Other solutions could include ultrasound, capacitive, conductive, or even other methods - those all depend on the material measured whether they work in the first place, and require calibration for each different material.