DAF/CK < DAFCAT: CK CONCATENATION > BIG-IEEE FTPSTR: : : : :::ENDFTP \beginlabel PDS_VERSION_ID = PDS3 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 1024 ^SPICE_KERNEL = "ds1_sa_2000.bc" MISSION_NAME = "DEEP SPACE 1" SPACECRAFT_NAME = "DEEP SPACE 1" DATA_SET_ID = "DS1-A/C-SPICE-6-V1.0" KERNEL_TYPE_ID = CK PRODUCT_ID = "ds1_sa_2000.bc" PRODUCT_CREATION_TIME = 2003-10-06T10:32:32 PRODUCER_ID = "NAIF/JPL" MISSION_PHASE_NAME = "CRUISE 2" PRODUCT_VERSION_TYPE = ACTUAL PLATFORM_OR_MOUNTING_NAME = "DS1 SPACECRAFT BUS" START_TIME = 2000-12-05T00:00:01.366 STOP_TIME = 2000-12-14T23:59:35.291 SPACECRAFT_CLOCK_START_COUNT = "3/0066754654.195" SPACECRAFT_CLOCK_STOP_COUNT = "3/0067618627.195" TARGET_NAME = "N/A" INSTRUMENT_NAME = "SOLAR ARRAYS" NAIF_INSTRUMENT_ID = { -30202, -30201 } SOURCE_PRODUCT_ID = "N/A" NOTE = "See comments in the file for details" OBJECT = SPICE_KERNEL INTERCHANGE_FORMAT = BINARY KERNEL_TYPE = POINTING DESCRIPTION = "DS1 solar arrays reconstructed orientation SPICE C-Kernel file created by NAIF, JPL, covering year 2000. " END_OBJECT = SPICE_KERNEL \endlabel DS1 Solar Array Orientation CK File for 2000 =========================================================================== Created by Boris Semenov, NAIF/JPL, Wed Oct 1 09:09:51 PDT 2003 Orientation Data in the File -------------------------------------------------------- This file contains orientation and angular rate data for the Deep Space 1 (DS1) Solar Array 1 (SA) and Solar Array 2 (SA2) frames. The orientation of the 'DS1_SA1' is given with respect to the 'DS1_SC_BUS' frame ; orientation of the 'DS1_SA2' is also given with respect to the 'DS1_SC_BUS' frame. The NAIF IDs for the 'DS1_SA1' and 'DS1_SA2' frames are -30201 and -30202. Status -------------------------------------------------------- This file was created by NAIF for archiving with the Planetary Data System (PDS) from daily CK files produced by NAIF, JPL. Pedigree -------------------------------------------------------- The original CK files used to create this file were officially delivered to the DS1 project by the NAIF Team. These files contained the solar array frames orientation with respect to the spacecraft frame. The orientation was computed on the ground from the solar array gimbal angles extracted from the channelized telemetry sent down by the spacecraft. The individual daily CK files were merged together at the time of archiving. A table containing the complete list of original CK files from which data were inclu ded in this file is provided at the end of these comments. Approximate Time Coverage -------------------------------------------------------- This file covers the following interval: Coverage Begin UTC Coverage End UTC ------------------------ ------------------------ 2000-DEC-05 00:02:32.366 2000-DEC-14 23:59:35.290 This file is a type 3 CK file which provides linear interpolation between orientation data points extracted from telemetry. Such interpolation is not applied to the whole coverage of the file but only inside intervals where enough orientation telemetry data was available and orientation data points were close to each other in time for such interpolation to make sense. The nominal gimbal angle time spacing in the telemetry stream varied from one to many seconds between adjacent data points. Considering that the array gimbals cannot rotate very fast and that the highest accu racy of the SA orientation knowledge is unlikely to be needed in any application, the duration of the longest interval over which the data may be interpolated was set to 300 seconds. For all requests for data falling between two adjacent data points separated by more than 300 seconds the SPICELIB CK readers will return a logical flag stating "POINTING NOT FOUND". A table containing the complete list of valid interpolation intervals in the file segments is provided at the end of these comments. Angular Rate Data Note -------------------------------------------------------- Since DS1 s/c engineering telemetry did not contain angular rate data for the gimbals, the angular rates stored in this file were computed from the orientation information. The angular rate for each orientation point was computed as average of two rates -- constant angular rate that would rotate from previous point to that point and constant angular rate that would rotate from that point to the next point. Because angular rates stored in two adjacent points in most cases are not the same, and CK readers linearly interpolate between them, the output angular rates in general will never be constant between any two adjacent data points stored in the file. Usage Note -------------------------------------------------------- In order to use this file an DS1 SCLK file containing coefficients mapping DS1 on-board time to ET must be loaded into a user's program. Loading an DS1 Frames Kernel (FK) containing information that SPICE software need to combine gimbal orientations together will allow a user to get the combined orientation through the high level SPICE Toolkit interfaces. Related Kernels -------------------------------------------------------- This file was created using the following LSK and SCLK files: naif0007.tls ds1_sclkscet_00071.tsc Contacts -------------------------------------------------------- If you have any question regarding this data contact NAIF at JPL: Charles H. Acton, Jr (818)-354-3869 chuck.acton@jpl.nasa.gov Boris V. Semenov (818)-354-8136 boris.semenov@jpl.nasa.gov Appendix 1: List of the original CK files -------------------------------------------------------- ds1_sa_ck_2000-12-05.bc ds1_sa_ck_2000-12-06.bc ds1_sa_ck_2000-12-07.bc ds1_sa_ck_2000-12-08.bc ds1_sa_ck_2000-12-09.bc ds1_sa_ck_2000-12-10.bc ds1_sa_ck_2000-12-11.bc ds1_sa_ck_2000-12-12.bc ds1_sa_ck_2000-12-13.bc ds1_sa_ck_2000-12-14.bc Appendix 2: Interpolation Intervals in the File -------------------------------------------------------- The information in this section has been generated by running CKBRIEF utility program using -dump -utc command line options. CKBRIEF Version: 2.0.0, 2001-05-16. SPICE Toolkit Version: N0056. Summary for: ds1_sa_2000.bc Segment No.: 1 Object: -30201 Interval Begin UTC Interval End UTC AV ------------------------ ------------------------ --- 2000-DEC-05 00:02:32.366 2000-DEC-14 23:59:35.290 Y Segment No.: 2 Object: -30202 Interval Begin UTC Interval End UTC AV ------------------------ ------------------------ --- 2000-DEC-05 00:00:01.365 2000-DEC-14 23:59:35.290 Y @ Bǫ B B B DS1 SA1 Gimbal CHTLM - Made-up AVs DS1 SA2 Gimbal CHTLM - Made-up AVs ?쉚[: u dWi ?0j |Lc dWi ?0j |Lc dN1 ?{h bI >d` ?싋8 ف >6 ?싋8 ف ?싋8 ف >dN8X ?@k # 6