Candidate: Artur Tozzi de Cantuaria Gama 
Program: UFSC / POSMEC
Date: March, 2020
Advisor: Victor Juliano De Negri
Co-Advisor: Rafael Rivelino da Silva Bravo
Resumo: Aiming to reduce the consumption of fossil fuels, one focus in engineering is the study of al-ternative or hybrid solutions for motor vehicles. This study is based on a parallel hydraulic-pneumatic hybrid proposal for trucks and buses for energy recovery during periods of braking for later reuse in the generation of compressed air and acceleration. In most hybrid hydraulic solutions, a pump/motor is used to apply a decelerating torque and charge the hydraulic accu-mulators, that have high power density and are capable of absorbing part of the available ki-netic energy. This idea is expanded in the case under study through the inclusion of an air compressor coupled to a hydraulic motor present in the proposed circuit to charge the air res-ervoirs, so that the potential energy available when the vehicle travels on a slope for long peri-ods can also be recovered. The usage of this hydraulic circuit depends on the system capability to decide when and how to apply it to meet the driver’s acceleration and braking demands, therefore a mathematical model of the system available on MATLAB/Simulink® is used for the implementation of a heuristic supervisory control that shall identify the vehicle’s operating states and activate the appropriate operating modes. In order to develop a strategy to be used on different drive cycles, a method to evaluate the system will be presented based on state machines, more specifically on the statechart theory and implemented in the model with aid of the Stateflow® library, that, since it is a graphical tool, assists the process of detailing the con-troller and facilitates parameters modifications, operating modes implementation and system integration. Finally, the results obtained through simulations will be shown, as well as an anal-ysis of the vehicle behavior and the hydraulic-pneumatic system performance under different work cycles to confirm the applicability of the proposal.
Referência: GAMA, A. T. C. Desenvolvimento de um controlador supervisório com máquinas de estado aplicado a veículos comerciais com sistema de hibridização hidráulico-pneumático. 2020. 143 p. Dissertação de Mestrado em Engenharia Mecânica. Universidade Federal de Santa Catarina, Florianópolis.
