Hi Perez,
Thank you for your question. There are two methods of monitoring pressure and weight using RFMicron sensors. Method #1 uses one of our moisture sensors and has a piece of metal move closer to the sensor as the pressure increases. The highly accurate pressure sensors use this approach. The downside of this approach is that the cost of the metal apparatus goes up with improving accuracy. Method #2 also uses a moisture sensor and has a piece of closed-cell foam with a small piece of metal foil over the moisture sensor area. As the pressure or weight increases, the foil is pressed closer to the sensor. The sensor detects the change and reports the value. This type of weight sensor provides a reasonable estimate of the object’s weight.
The newest RFMicron IC supports external sensing elements, like load cells, strain gauges, etc. This might be your best option for weight and pressure measurements. We will have full sensors later in 2017 that allow you to add your own sensing circuitry.
thanks