Sistema de aquisição de dados e condicionamento de sinais para medição de desempenho de veículo Baja SAE

Abstract

The Baja SAE (Society of Automotive Engineers) project, is a challenge to the students, which enables the future engineers to apply their knowledge on the project and manufacturing of an off-road vehicle. The finality of the electrical system embedded in the prototype, is to assure the security of the pilot while driving, through data acquisition and display, and also get data for project validation and improvement over time. As an important system for security and project evolution, and considering the harsh environment where the vehicle operates, the development of a reliable data acquisition and signal conditioning system is necessary. Based on the motivation presented, the pertinent variables to be measured were determined, both for presentation to the pilot and team monitoring. The selection of the appropriate sensors for each case was implemented by a specific method, taking into consideration points like cost and applicability to a Baja SAE project environment. It was developed the project of signal conditional circuits, to ensure the reliability of digital and analog signals acquired from the sensors, which were posteriorly tested individually by software simulation and bench test. Two PCBs (Printed Circuit Boards) were designed to integrate the whole system, composed by sensors, signal conditional circuits, power circuits, microcontrollers and, other integrated circuits. Calibrations of the analog signals were done to obtain equations that relate the read values from the microcontrollers with the physical phenomenon measured. In the validation process, several dynamics tests were performed with the proposed system embedded in the prototype, in which the final results about the system behavior were obtained by the analysis of acquired data for each variable. The final results obtained testify operation of the acquisition system, which is ready to be installed in a Baja SAE prototype.