Patent ID: 7905177

Claim:
A safe and arm system comprising: an operator control subsystem including: a first arm switch including a safe state and at least one armed state, a second arm switch including a safe state and an armed state, and a fire switch including a safe state and a firing state; and a fire control subsystem responsive to the operator control subsystem and including: at least a pair of terminals for connection to a munition, the terminals initially shorted together and without a ground, a power supply control circuit including a first microcontroller configured to supply power to the terminals, a ground supply circuit including a second microcontroller configured to ground one said terminal, and a terminal shorting circuit including a third microcontroller configured to remove the short across the pair of terminals, the power supply control circuit, ground supply circuit, and terminal shorting circuit configured to ground one terminal, remove the short across the pair of terminals, and to supply power to the terminals only if the first and second arm switches and the fire switch are all activated from the corresponding safe state in a predetermined sequence, each microcontroller configured to monitor at least one other microcontroller to ensure the microcontrollers agree said predetermined sequence has occurred within a predetermined time before said one terminal is grounded, the short across the pair of terminals is removed, and power is supplied to the terminals.