Designing a safety circuit to ignite a pyrotechnic device

[ih96]

Hi, I have been given a project to design a circuit which will ignite a pyrotechnic flare after a certain sequence of events has been detected. The events which must be detected are:

-A specific signal transitions from a short circuit to an open circuit.
-A short pulse signal from a separate detector is received.
-A 5V logic signal transitions from logic 0 to logic 1.

Additionally, the sequence in which these events occur is unknown.

I have a massive interest in electronics but only a limited knowledge which I have gained from my university course (Physics), so I am struggling to know where to begin with this project. I need advice on which components the circuit should contain in order to detect these events and if wiring them in a particular way may work better than others. I'm kind of viewing this as a learning experience, any suggestions or explanations offered will be thoroughly appreciated. I will do my best to try to understand!

[pebe]

More information is needed in order to provide a circuit. For instance:

"-A specific signal transitions from a short circuit to an open circuit".
What will be the open circuit voltage and polarity of the open contacts?

"-A short pulse signal from a separate detector is received".
How long is the pulse and what is its amplitude and polarity? Is ignition to take place during the pulse?

"-A 5V logic signal transitions from logic 0 to logic 1".
How do the (absolute) voltage levels of this 5V logical signal compare to those of the previous two requirements?

[ih96]

More information is needed in order to provide a circuit. For instance:

"-A specific signal transitions from a short circuit to an open circuit".
What will be the open circuit voltage and polarity of the open contacts?

"-A short pulse signal from a separate detector is received".
How long is the pulse and what is its amplitude and polarity? Is ignition to take place during the pulse?

"-A 5V logic signal transitions from logic 0 to logic 1".
How do the (absolute) voltage levels of this 5V logical signal compare to those of the previous two requirements?

Hi, thanks for responding. I don't know what else to add because I posted all the information I was given. The only thing I think I can answer is that the ignition would take place after the pulse, as the circuit is meant to be designed so that ignition occurs only when all three events have taken place. I can only imagine that it is acceptable to make assumptions as to the other specifications. Sorry I can't give more information!

[pebe]

Then I think you should tell your information provider that there is insufficient information to give an answer.