A presence sensor system includes at least one resilient extending member defining an enclosed sensing volume. The sensing volume includes a fluid therein. A pressure within the sensing volume changes upon application of force to the extending member. The presence sensor system further includes a pressure sensor in fluid connection with the sensing volume, a processor system in communicative connection with the pressure sensor and a communication system in communicative connection with the processor system. In a number of embodiments, the presence sensor system is adapted to determine a pressure threshold associated with onset of presence after being placed in use.