The AFES is an electro-hydraulic inertial exciter system capable of creating controlled sinusoidal forces up to 400 lbs (1780 N) over a frequency range of 3 Hz to 15 Hz. Force is generated by the acceleration of a 250 lb (114 kg) mass by a hydraulic exciter with a 4 inch (100 mm) maximum stroke and a 600 lb (2670 N) force capability. The actuator is controlled by a dual loop controller which maintains the mass oscillating about a center position by monitoring an LVDT. while peak force is compressor controlled by monitoring the exciter’s strain gage load cell. The actuator is powered by a 3000 PSI (206 E5 Pascal), 5 GPM (20 lpm) hydraulic power supply.
The complete AFES is powered by an aircraft’s 400 Hz 125 v 3 phase power system and 50/60 Hz 120/240 v power system. System inputs consist of 28 V relay hydraulic start / stop and 1.0 V sinusoidal output from an external signal source. The system supports dwells and sine sweep testing with rates from 0.1 to 3.0 octaves per minute.
The complete system has been qualified by Wyle Laboratories, Huntsville, AL, to meet MIL-STD-810F for Rapid Decompression, Temperature, Pressure, Random vibration, and Minimum Structural Integrity Test. Calculations verified compliance with Ultimate Load Factors of 6 g (up), 12 g (down) 3.5 g (lateral) and 2 g (fore and aft) and Survivable Crash Loads of 16 g (forward).
Wyle Laboratories has certified the AEFS to MIL-STD-461E for control of Electromagnetic Interface Characteristics of Subsystems & Equipment in compliance with: