In this thesis, we focus on flexible haptic feedback applications which rely on the sensation of touch to display a feedback to the user that establishes a system to user interaction. Piezocomposites made of piezoceramic and polymer phases can be used here due to their high flexibility and piezoelectric properties that enable them to deform under an electric field. A lead-free piezoceramic: KNLN-3 has been chosen as the ceramic phase due to lead-based ceramics having issues with toxicity and dielectric mismatch in composites. A flexible polymer: CFE was chosen as the polymer phase due to its high dielectric constant that decreases the dielectric mismatch to the maximum extent. The first objective of this thesis is to optimize the scale-up in production of KNLN-3 when employed as a random 0-3 composite. Thus, the production of KNLN-3 was analyzed with respect to the microstructure, purity, surface topology, poling, lithium content, precursors used and correlated with its performance in a composite. Based on this set of data, an optimized powder was obtained. The second objective of thesis was to perform mechanical tests on a composite made with this powder to obtain mechanical properties that quantify its effectiveness as a flexible haptic feedback device. From these tests, the optimized powder was seen to be the most ideal when it was employed as an R50 (0-3 composite with 50 % filler) composite with no glass fibres used during production.

Batteries are vital sources in many wireless embedded systems applications like the Tire Pressure Management System (TPMS) in the automobile industry. Also, the growth of electric cars will result in an increasing demand for batteries. Although batteries do not directly pollute the environment during their active life, the production phase and decomposition phase will contribute to pollution. The limited lifetime of batteries also emphasizes the need for a change to new technologies.
Replacing batteries becomes difficult in applications on desolated places. Energy harvesting can be an attractive alternative solution. Techniques like electrostatic, electromagnetic and piezoelectric energy harvesting can convert the energy in the ambiance to an useful electrical energy. Piezoelectric energy harvesting can be useful as they have been proven vital in converting vibration energy to the required form. This research focuses on powering wireless systems like a TPMS in a car by piezoelectric energy harvesting. It provides the requirements and decisions involved in designing a circuit capable of transferring input energy to output in an efficient manner. The circuit rectifies the output of a piezoelectric material and provides an output of 3.3 V. Result showed that the circuit was able to power an LED for 5.8 s. By adjusting the circuit according to the power requirements, the circuit can be the source to low power wireless embedded systems.