Riassunto analitico
This project focuses on developing the automatic test control and alarm management system software using Labview custom tool and Veristand software in accordance with National Instruments data acquisition system (NI cDAQ 9188) and various data capturing cards.
Three main controls were added in existing automatic test control software which are Alarm’s deactivation and management in the automatic test, recording file management during long unattended reliability test and Introduction of a restore point for the automatic test. Addition to this alarm management system based on look up table was implemented in the manual testing software.
The first feature which was implemented in the original software was to change the way of recording and storing the data during automatic test. Now, the data is recorded only when the engine is running and save them as per the velocity profile for each loop in a separate file with the name of the loop unlike in original software where all the data were saved in a single file starting from opening of automatic test interface till it was closed. This feature made it lot easier for the user to analyze the data and maintain the reference with the test conducted.
Second feature which was added is allowing user to activate and deactivate the alarm during specific steps of velocity profile in order to allow the execution of the transient steps that are not dangerous for the engine. In fact, the alarms thresholds that for safety reason allow very tight tolerances, are suitable for the long steady state operation but often, during the short transient in the cycle, are likely to be overcome.
Next feature was to allow the user to start the automatic test exactly from the point where the last test was stopped instead of forcing the user to start the test from the beginning in case the test was stopped due to alarm or any other reason and the test was incomplete in addition this feature also provides many information related to the progress of test which made it lot easier for the user to get the idea of previous test conducted and decide for the new test.
Finally, LUT (Look up table) based Alarm system was implemented. The existing control software in Ducati test bench allows user to setup alarm using fixed threshold value with respect to each input channel in this way the user could only define the maximum and minimum allowed values for each channel. The thresholds must be large enough to include all the possible values acquired by the sensor along the whole range of operating points. Having such large maximum and minimum value for this type of channels is not suitable for detecting quickly a malfunctioning. This is where this feature focuses to eradicate this problem and develop a reliable and quick responsive alarm system by adapting the thresholds to the actual operating point of the engine so that the alarm limits are not merely represented by the maximum and minimum values that can be acquired by the channel. Instead of comparing the absolute reading of the quantity needed to be monitored with the upper and lower fixed limits, the idea is to create a look up table whose axes report the breakpoints of two variables that together define the working condition of the engine, and whose cells contain the nominal values expected for the channel monitored. The alarm is going to be triggered as soon as the channel value deviates from the nominal value of the amount specified by the user.
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Abstract
This project focuses on developing the automatic test control and alarm management system software using Labview custom tool and Veristand software in accordance with National Instruments data acquisition system (NI cDAQ 9188) and various data capturing cards.
Three main controls were added in existing automatic test control software which are Alarm’s deactivation and management in the automatic test, recording file management during long unattended reliability test and Introduction of a restore point for the automatic test. Addition to this alarm management system based on look up table was implemented in the manual testing software.
The first feature which was implemented in the original software was to change the way of recording and storing the data during automatic test. Now, the data is recorded only when the engine is running and save them as per the velocity profile for each loop in a separate file with the name of the loop unlike in original software where all the data were saved in a single file starting from opening of automatic test interface till it was closed. This feature made it lot easier for the user to analyze the data and maintain the reference with the test conducted.
Second feature which was added is allowing user to activate and deactivate the alarm during specific steps of velocity profile in order to allow the execution of the transient steps that are not dangerous for the engine. In fact, the alarms thresholds that for safety reason allow very tight tolerances, are suitable for the long steady state operation but often, during the short transient in the cycle, are likely to be overcome.
Next feature was to allow the user to start the automatic test exactly from the point where the last test was stopped instead of forcing the user to start the test from the beginning in case the test was stopped due to alarm or any other reason and the test was incomplete in addition this feature also provides many information related to the progress of test which made it lot easier for the user to get the idea of previous test conducted and decide for the new test.
Finally, LUT (Look up table) based Alarm system was implemented. The existing control software in Ducati test bench allows user to setup alarm using fixed threshold value with respect to each input channel in this way the user could only define the maximum and minimum allowed values for each channel. The thresholds must be large enough to include all the possible values acquired by the sensor along the whole range of operating points. Having such large maximum and minimum value for this type of channels is not suitable for detecting quickly a malfunctioning. This is where this feature focuses to eradicate this problem and develop a reliable and quick responsive alarm system by adapting the thresholds to the actual operating point of the engine so that the alarm limits are not merely represented by the maximum and minimum values that can be acquired by the channel. Instead of comparing the absolute reading of the quantity needed to be monitored with the upper and lower fixed limits, the idea is to create a look up table whose axes report the breakpoints of two variables that together define the working condition of the engine, and whose cells contain the nominal values expected for the channel monitored. The alarm is going to be triggered as soon as the channel value deviates from the nominal value of the amount specified by the user.
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