- Fill out requirements 3.1 Angelina Costa
- Fill out requirements 3.2 Asael Acosta
- Fill out requirements 3.3 Eddy Chen
- Finish filling out RS-422 Decision Angelina Costa
Scheduling Notes:
Our payload's communicating with the BUS on the oligo satellite → dominant concerns are reliability, determinism (data arrives in predictable time frames), and respecting internal BUS operations
Housekeeping/Scientific is what we communicate to the OBC and Command is what gets communicated to us
| Housekeeping | Scientific | Command/Critical |
|---|---|---|
| Highest Priority | Secondary Priority | Not as frequently sent, preempts others |
| High priority transfer at quickest intervals | Communicated less frequently, maximized while respecting OBC memory | Infrequent, not up to us |
| 0.2 - 1 Hz | Might vary between the pressure (10-100 Hz) and temperature sensors (1 Hz) |
There's no hard and fast protocol for packet scheduling. Those are decided on a case-by-case basis:
- How often we fly over a listening ground-station (Need to ask Oligo)
- No point broadcasting if no one's listening
- On-board memory (Is this on our payload or the OBC?)
- determines how much we can store/queue up between passes
- Sample rates
- Low in our case, order of 10 Hz
- could be higher for the pressure sensor, in case we want to be as sensitive as possible for sudden pressure changes in the tank
- Temperature and Pressure change slowly, so the slower sample rate is permitted
- Back of napkin calculation (assuming 24 bytes stores one data entry for each sensor):
- 24 bytes * 10 Hz * 3600 s/hr = 5.184 MB (decimal)
- Low in our case, order of 10 Hz