Abstract: Disclosed herein are related to a touch sensitive device. The touch sensitive device includes a panel with a surface including a tactile interface, where the tactile interface has surface variations forming a tactile pattern. In one aspect, tactile interaction with the tactile pattern produces an energy signature representative of the surface variations. In one aspect, the touch sensitive device further includes an electro-mechanical transducer configured to generate an electrical output signal in response to detecting the energy signature. In one aspect, an output of the electro-mechanical transducer is connectable to a processor configured to produce a control signal based on the electrical output signal of the electro-mechanical transducer.