Greenfield, Terry | Search NASA

NASA NTRS2009

Pyrotechnic Simulator/Stray-Voltage Detector

The concept for a dual test item has been developed for use in simulating live initiators/detonators during ground testing to verify the proper operation of the safing and firing circuitry for ground and flight systems ordnance as well as continuous monitoring for any stray voltages. Previous ordnance simulators have consisted of fuses, flash bulbs, inert devices with bridge wires, and actual live ordnance items mounted in test chambers. Stray voltage detectors have included devices connected to the firing circuits for continuous monitoring and a final no-voltage test just prior to ordnance connection. The purpose of this combined ordnance simulation and stray-voltage detection is to provide an improved and comprehensive method to ensure the ordnance circuitry is verified safe and operational.

Greenfield, Terry↗

NASA NTRS2008

Programmable Low-Voltage Circuit Breaker and Tester

An instrumentation system that would comprise a remotely controllable and programmable low-voltage circuit breaker plus several electric-circuit-testing subsystems has been conceived, originally for use aboard a spacecraft during all phases of operation from pre-launch testing through launch, ascent, orbit, descent, and landing. The system could also be adapted to similar use aboard aircraft. In comparison with remotely controllable circuit breakers heretofore commercially available, this system would be smaller, less massive, and capable of performing more functions, as needed for aerospace applications.

Greenfield, Terry↗