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The paper addresses the development of an electromagnetic brake control and data capture of torque and rotation, using a graphical interface implemented in LabVIEW for evaluating the performance of internal combustion engines. To control the electromagnetic brake is used like a SMPS Buck, and programming interface developed in LabView is responsible for generating the pulses of voltage that feeds the brake and the data capture system. This project started with the need for improved equipment control and data acquisition dynamometers, eddy-current, installed at the Automotive Laboratory, Instituto Federal de Santa Catarina (IFSC). In the system of control and data acquisition parameters can be added as temperatures, pressures etc., further improving the precision of torque and power these devices.

The paper addresses the development of an electromagnetic brake control and data acquisition system to capture speed and torque. LabVIEW™ was used to implement a graphical interface to evaluate the performance of internal combustion engines. This graphical interface allows processing and displaying the signs in their appropriate units, and also the refinement of data in the desired tracks, in ways to evaluate the power and torque curves. This project started with the need to improve research equipment control and data acquisition on eddy-current dynamometers that are installed in the ADeMCI research group of the Instituto Federal de Santa Catarina (IFSC). In the control system and data acquisition parameters other variables can be added, such as temperatures, pressures, etc., this will promote further improvement in the precision of torque and power reading with this device.

The purpose of this project is to develop and test a technological adaptation in an internal combustion engine to increase its efficiency and the reliability of its system of monitoring and measurement of power. Such engines are used as propellants in reciprocating compressors of natural gas (NG) in compression stations installed in the company TBG S/A (owner and operator of the Bolivia Brazil Pipeline). These compression stations receive NG at a pressure of up 58kgf/cm2 and compress natural gas at a pressure of up 75kgf/cm2. Currently the measurement of power expended by the compressors that compress the NG does not happen precisely; this measurement is an important parameter for the operation of the equipment. After studies, it was found that this lack of precision is one of the factors that sometimes cause the operation of compressors off the power range recommended by the engine manufacturer.

Integrated controls for commercial dynamometers do not have appropriate characteristics to perform research and teaching tasks. These are developed to perform quick tests and its logic is prepared to obtaining the information in accordance with the technical standards. This way, the use for research is hindered because it does not have an interface that allows a refinement to the desired data ranges, t data sampling and the type of load that is applied. Its use for teaching is limited because these "standard" controls does not allow to analyze or to determine engines characteristics that are not covered through tests specified by the standards, so the use of this tool as an important part in professional training formed by the institution.

In a test bench for automotive shock absorbers the angular velocity of the "scotch yoke" mechanism must be constant, but the load (resulting from shock forces) varies in function of the speed, resulting in fluctuations in the speed along the course of the test, in function of the frequency variator response time controlling the electric motor. Employing a closed loop control system for the automotive shock absorber tests will result in tests with better quality at higher speeds and loads, thus enabling a better representation of the shock absorber condition. The paper presents the state of the art and research in development that is linked to closed loop control mechanisms. It is developed a control system which allows maintaining a constant test speed, independent of the load reaction to a range of shock absorber tested, as a function of resultant load. The mathematical modeling of the problem is presented, quantifying the magnitudes involved.

The use of dynamometers, especially inertial ones, has been widespread in Brazil in recent years. This increase in the use of the tool has several reasons, among them the greater availability of equipment, price reduction and the appearance of programmable electronic injections. Programmable injections, for better engine performance, must be adjusted in the different conditions of use and in the different points of the injection and ignition maps. This adjustment could be made by driving the vehicle on streets or in a proving ground, however the torque and power gain cannot be measured with sufficient precision to decide the ideal ignition timing and injection time. The inertial dynamometers marketed in the country, and used in repairers or vehicle preparers always bring software that allows the acquisition and registration of the information obtained in the tests.