DRAFT, NOT FINISHED
Simon C. O. Grocott. Dept. director, missions. Tor Arne, Mariusz, Roger
Simon has a question about absorption through the atmosphere vs. irradiance from the atmosphere. Ref. Mariusz slide 20.
Signal from the surface will be absorbed through the atmosphere. In addition the atmosphere will "reflect"/irradiate at the same time... --> Both effects come into play?
Question on what kind of partnership we want. --> We want an active partner, more than a pure supplier.
UTIAS:
Self-funded, not-for-profit. All funding from contracts. 35 engineers, 15 grad students.
Have 18 sats operational. 15 awaiting launch.
Can vere open for utveksling/research stays. Some things rely on the university itself. Maybe not a lot of opertunities?
Smallsats are a design approach, not a size.
Not doing a lot of CubeSats, but are open for it, esp. if its a longer series of satellites.
Integration of spacecraft on-site (NTNU) can be feasable.
Launch: Have supported a wide range. (Must get a up-comming manifest).
Typical orbits are 500-650, 09:30 - 10:30 acending/decending node.
Does not see any immediate pit-falls.
Sleep-power: Will be higher than "expected", need to keep a reasonable amount of minimum operations in order to ensure good operation and wake-up. 3 - 4 W.
Attitude: Must look into this exp. on 3U. On bigger buses this is less of an problem. Pointing knowlegde with star-tracker is very good. Pointing accuracy its more challenging, but should be better than 0.5 deg if good calibration. During slew, should be at 0.2-0.1 during manuvers. The type of reaction wheels must be looked into for 3 U. A bit more of a challenge.
Limb-to-limb pointing might be a issue. Where can the star-tracker point. Must avoid sun into the sensor too. Higher latitudes should be fine, but further south might be more of an issue. Can be a bit of a time-variance wrt. position of sun/moon/earth-interactions.
Have GPS, better than 10 meters.
S-band down, UHF up. Active pointing of the antenna. 2 Mbps (with pointing). Standard, nominal, mode is more like 128 kbps --> works for all attitudes.
Uplink is typically 4 kbps. Have always supported re-programming.
Spend a day to upload the file, then do verification and load.
Operations software are available. Encourage testing using operational software during test on ground. FFI and Statsat have this.
Training: Can happen at UITAS, or NTNU.
Have a flat-sat, made up by spares. Could then be used as spares for the flight model if needed. Does not really make an EM of flight heritage components. Go right to proto-flight if its only small changes. Does not expect any new equipment, but will probably have some suggestions on how to build the payload.
On-board interfaces: Limited to 1 Mbps or 500 kbps. CAN or serial of some sort. Should have around 1 GB storage on the onboard-processing. Also used as buffer before transmit. Have a NSP (nanosat communication protocol).
OS: Cano. In-house system. Not really open for us. ADCS is probably not really acessable; perhaps with permission. Could provide some interface of to software that we could run.
Interaction between payload and OBC: SHould be limited to data exchange. Commanding should go through mission planning software (GS). Upload target, time, when. Time-tagged commands. Not any feedback on what going on. Onboard autonomy means different things.... Using a hand-full of high-level commands. Like "point here", take image. The detailed maneuver will be solved in the space craft.
Could be able to operate on input from the payload, but perhaps go through the GS first.
Does not currently have SDR.
Formally: Need an export agreement, should not be a problem. Need to look into which students can be in the project and so on.
Next steps:
UTIAS: Inform Rob, internal discussion. Size of spacecraft, sharing agreements and so o.
Need some more requirements in order to get a ROM.