Modelling of complex haptic effects using piezoelectric actuators

The following work consisted in an in deep study of haptic effects for contact-based feedback, reproduced by the use of piezoelectric actuators based on Aluminum Nitride and Lead Zirconate Titanate; through their modelling supported by the use of the software COMSOL. Two main effects are then described theoretically, which are known as “Squeeze Film” and “Time Reversal”, followed by the creation of models in the software that are able to represent the relevant properties of those phenomena separately. Then, a model which is able to reproduce both effects simultaneously is given, and the same is optimized for power consumption. As a last step, a layout is created that allows the integration of the power-optimized design into a substrate. It is found through this work that in fact it is possible to recreate both effects independently and simultaneously, with an arrangement of piezoelectric actuators that increases in complexity and number of elements depending on parameters like the frequency of operation and the substrate thickness. The design created for multiple effect recreation allows to reproduce both with a power consumption of about 250 mW, which means it could be integrable in actual portable devides, like smartphones or tablets. Finally, it results necessary then to invest in the study of production of transparent piezoelectric actuators, which would allow for the designs presented in this work to be become available for integration into the market.