This thesis presents the design, implementation, and validation of a piezoelectric energy harvester (PEH) emulator to enable repeatable evaluation of energy extraction circuits for vibration-based systems. PEHs convert mechanical vibrations into electricity using materials that generate charge under stress, offering compact, maintenance-free power for low-power electronics.
Efficient energy extraction from PEHs requires specialized circuits whose performance depends heavily on the PEH’s electrical characteristics. However, real PEHs often exhibit nonlinear and chaotic behavior, complicating consistent testing and comparison. The proposed emulator overcomes this by replicating PEH electrical behavior in a controlled, configurable, and repeatable way.
The emulator employs a voltage-controlled voltage source with analog impedance modeling, supporting output ranges up to ±25 V and 3 A. It includes modular impedance matching and real-time responsiveness without digital latency. A complete prototype was built and tested. Simulations showed stable operation under various conditions, and experimental results demonstrated 80–100% accuracy in reproducing PEH power output.
To the author's knowledge, this is the first emulator designed specifically for PEHs, addressing a gap in existing literature. While emulators are common in photovoltaic and thermoelectric domains, none existed for piezoelectric harvesters. This work establishes a flexible benchmarking platform and outlines paths for improving emulator accuracy via improved impedance modeling and alternative architectures.

Technology is playing an increasingly important role in education, partially thanks to emerging teaching methods such as hybrid education. Smart classrooms equipped with technology can make the lives of the educators and students easier, and aid in the switch to hybrid education. In this work we propose an IoT based smart classroom framework to create a base for smart classroom applications. Using this framework, multiple applications are manifested in the form of prototypes. One prototype introduces wireless sensor readout capabilities. The other prototype focuses on assisting the lecturer in a hybrid teaching setup. Using the prototype, the teacher is able to control whether online students are able to hear the students who are physically present and vice versa. The prototype also includes a way of indicating a question from an online student.