Its happened to almost all of us who fly electronic deployment. Something unexpected happens and the altimeter suffers a hiccup in power that causes it to reset.
My question is, why don't the altimeters have an in-flight recovery feature? I'm not aware of any commercial altimeter that has this feature, but it seems like it wouldn't be too hard to code up.
You could store a simple variable in EEPROM that tells the flight computer what the last event was. Read this variable at startup and if it wasn't "touchdown," then it could attempt to recover by quickly running an emergency recovery routine. This routine could sample the sensors, and then based on what was found, determine where the rocket is in flight. If the sensors determine the rocket is on the pad, then go back to the beginning and start with a normal powerup sequence.
One could also get more sophisticated with some inflight fault detection. If a bad e-match or short in the pyro wiring is causing a brownout, then it could choose to do other things. For example, if the apogee pyro is shorted and can't fire the ematch, on the second emergency recovery cycle the altimeter could fire the mains. I'd rather blow the main near apogee than come in ballistic.
I'm coding this up right now on my own flight computers. Considering how many times I've seen this happen to other flyers, and the potential increase to overall safety, I'm curious why this hasn't been pursued. Let me know if you have thoughts.
My question is, why don't the altimeters have an in-flight recovery feature? I'm not aware of any commercial altimeter that has this feature, but it seems like it wouldn't be too hard to code up.
You could store a simple variable in EEPROM that tells the flight computer what the last event was. Read this variable at startup and if it wasn't "touchdown," then it could attempt to recover by quickly running an emergency recovery routine. This routine could sample the sensors, and then based on what was found, determine where the rocket is in flight. If the sensors determine the rocket is on the pad, then go back to the beginning and start with a normal powerup sequence.
One could also get more sophisticated with some inflight fault detection. If a bad e-match or short in the pyro wiring is causing a brownout, then it could choose to do other things. For example, if the apogee pyro is shorted and can't fire the ematch, on the second emergency recovery cycle the altimeter could fire the mains. I'd rather blow the main near apogee than come in ballistic.
I'm coding this up right now on my own flight computers. Considering how many times I've seen this happen to other flyers, and the potential increase to overall safety, I'm curious why this hasn't been pursued. Let me know if you have thoughts.