I quickly performed some ‘shake’ tests of the payload on the desk. I managed to get a test run which generated NO Air pressure and temperature measurements!. Then next time I turned it on, it froze up when trying to detect the air pressure sensor. Not good!
So I decided to pull the system apart and check out clearances between the air pressure sensor and surrounding electronics. The components are very close indeed. I proceeded to put some sticky-tape on both sides of the sensor to reduce chance of touching electronics on either side.
I have performed the shake test (quite violently) twice now without any issues, so I’d say that the close proximity and the vibrations in the rocket caused a momentary short. I was lucky that the Gyroscope measurements still worked
Fixes I’ll be looking at putting in are:-
- Minimum gap between components – 2mm
- Components supported opposite header pins for breakout boards.
- Programming of circuit to timeout if it has issues connecting/talking to a component.
In any case, we’ll be completely redesigning the PCBs. So these problems will be resolved then.