Vibration Testing of Absolute Pressure Sensor for a Flush Air Data System (FADS).

Flush Air Data Sensing System (FADS) is an important subsystem required for a winged re-entry vehicle. It essentially makes use of surface pressure measurements located at a suitable position in the vehicle for deriving the air data parameters of the vehicle such as angle of attack, angle of sideslip, Mach number, etc. These air data parameters are used by the control and guidance system for carrying out gain scheduling, trim scheduling of control surfaces and overall flight management. The accuracy of the pressure sensors used in FADS is critical in achieving the targeted accuracy of the air data parameters. In the FADS system considered in this paper, piezoresistive MEMS-based pressure sensors are used. The FADS system is located in the nosecone of the vehicle which is a region prone to vibration during transportation as well as during flight. It is essential that the pressure sensors perform with the desired accuracies in spite of the vibration environment. Sine and random vibration testing are carried out as part of qualification testing of the vibration sensors of FADS. Analysis of the test results shows that the accuracies demanded by the system are provided by the pressure sensors under the vibration environment. [ABSTRACT FROM AUTHOR]