Electromagnetic effect testing
A device comprises a circuit board, a Rogowski coil on the circuit board, persistent data storage on the circuit board, and a control circuit on the circuit board for collecting values representing current sensed by the coil, and storing the values in the persistent memory.
1. A method, comprising:
subjecting an aircraft structure to an electromagnetic effect (EME) event comprising an artificial source of EME current;
detecting the EME event on the aircraft structure using EME current sensing devices provided on circuit boards fastened to the aircraft structure;
storing EME current values for a first period immediately preceding the EME event;
storing EME current values for a second period after the EME event has been detected; and
constructing a full current waveform for the EME current values stored during the first and second periods, wherein the full current waveform includes a rise time of current induced by the EME event.
2. The method of claim 1 , in which the EME current sensing devices comprise Rogowski coils configured to generate transient pulses in response to EME current, and in which the EME current values stored during the first and second periods are based on the transient pulses.
3. The method of claim 2 , further comprising reducing noise in the transient pulses by positioning an integration and amplification circuit on each circuit board and proximate the Rogowski coil.
4. The method of claim 1 , in which the structure includes fasteners, and the EME current sensing devices are fastened to the fasteners, wherein detecting the EME event on the structure comprises detecting EME current flowing through the fasteners.
5. The method of claim 1 , further comprising:
storing the full current waveforms in a persistent data storage; and
after the EME event has ended, transmitting the full current waveforms from the persistent data storage to a base computer.
6. The method of claim 1 , further comprising retrieving the stored EME current values for the first period and for the second period after the EME event has ended.
7. The method of claim 1 , in which the EME current sensing devices comprise Rogowski coils provided on circuit boards fastened to the structure, each circuit board including a Rogowski coil surrounding one of the fasteners.