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FSW Requirement 5.3.11.3.2 (prev, next)

Req. 5.3.11.3.2: "Receive Attitude Data"

The SIU FSW shall receive spacecraft attitude data packets from the SC, delivered at the 5 Hz SC attitude control loop rate, via the CTDB. The data content of these packets is specified in [7].

Basis (help)

[1] (3.1.2.5.1.2), [2] (3.2.6.4)

    1: "Mission System Spec." (NASA 433-SPEC-0001)

      3.1.2.5.1.2: "Ancillary Data"

      LAT and GBM shall transmit data packets containing all data necessary for stand alone processing on the ground. (Calibration and alignment data will be constructed separately from science data sets.)

    2: "LAT Instrument - Spacecraft Interface Requirements Doc." (NASA 433-IRD-0001)

      3.2.6.4: "Ancillary Data"

      The SC shall provide an ancillary data packet to the LAT at a rate no more frequent than the SC GNC attitude control loop rate.

      3.2.6.4.1: "Ancillary Data Packet"

      The ancillary data packet shall contain data as specified in the LAT-SC ICD.

    7: "GLAST 1553 Bus Protocol Interface Control Doc." (1196 EI-S46310-000)

Context (help)

Test(s)

    010a: LAT Pointing Calculations

    This test shall verify that the SIU FSW can promptly transform pointing vectors reconstructed from event data between the LAT-relative coordinate system and the celestial coordinate system. The transformation shall be based on GPS, attitude, and orbit information provided by the S/C and the event time tag read in with each event. Using simulated events and simulated SC time/attitude data, the test will demonstrate the accurate reconstruction of the Monte Carlo-provided primary particle vector, in celestial coordinates.