Pyro is the important component of the systems which is used to ignite Missile. The proposed setup will be useful to approve the acceptance of the Pyro Production LOT after going through the scheduled tests for acceptance of the same
Pyro Test Setup shall be extensively used for acceptance of the Production Pyro LOT after due tests conducted on the same. Since it is an critical component accuracy and stability of the system should be very precise.
This test setup will inject current pulses to the pyro under testing and shall monitor the status by measuring pressure, temperature, current and flash detector. The temperature being optional for the same user can initiate test through their application.
Pyro Test setup shall be provided with three major modules. They are configurable constant current source, Data Acquisition Unit and Application.
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Using the constant current source module, required current amplitude and duration can be configurable by the user.
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Using the data acquisition unit user will be able to monitor and record the sensor data at very high data rates. This data will be stored with date and time stamp.
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The data can be retrieved in the form of a table providing absolute numbers as well as in a graph too. The same can be printed as when required by the user.
Each setup will have provision for two channels to test two pyros simultaneously.
Design Description of Modules:
Constant Current Source Module:
The constant current source is a hardware module which can be configurable. It shall be realised with the state of art devices. The constant current source will be designed using FETs. By controlling the FET bias the current will be changed. The bias voltage will be configured using digital potentiometer chip. These chips can be digitally configurable with microcontrollers. Hence the configuration will be accurate and reliable. FET and digital potentiometers are selected to accommodate the accuracy calibrations also.
Data Acquisition Unit:
Data Acquisition unit design will be based on 32 bit, ARM CORTEX microcontroller. The analog voltage/current measurement will be done using 24 bit ADC chips. The same controller will also configure the current source digitally as per user settings. This unit will have USB interface that can be interfaced to PC. The PC application can communicate with the microcontroller through this USB port.
The measured values shall be stored in an on board FLASH with date, time and unit number. This stored data will be uploaded to the PC application after the test.
The microcontroller will do calibration of the input ADC channels on every power ON. At the time of manufacturing the input channels will be calibrated and stored as factory defaults. The power on calibration will use these values as reference and if required fine tune them and use for that session of testing. If the power on calibration values differ from the factory calibration values beyond the predefined values, it will through error and ask for maintains calibration. In maintains calibration the factory defaults will be over written with new calibration values.
PC application software:
PC application will be used to configure the current source and collect the measured data after the test is completed. The data received shall be saved in CSV format. User can view the data as graph or as the raw numbers (in XLS format). Printing option also will be provided for printing the test results as per the need.
User can initiate self-calibration from the application and this self-calibration will be same as power on calibration.