KPL/IK \beginlabel PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM RECORD_BYTES = "N/A" ^SPICE_KERNEL = "MGS_MOC_V13.TI" MISSION_NAME = "MARS GLOBAL SURVEYOR" SPACECRAFT_NAME = "MARS GLOBAL SURVEYOR" DATA_SET_ID = "MGS-M-SPICE-6-V1.0" KERNEL_TYPE_ID = IK PRODUCT_ID = "MGS_MOC_V13.TI" PRODUCT_CREATION_TIME = 2000-12-19T13:45:53 PRODUCER_ID = "NAIF/JPL" MISSION_PHASE_NAME = "N/A" PRODUCT_VERSION_TYPE = ACTUAL PLATFORM_OR_MOUNTING_NAME = "MGS NADIR DECK" START_TIME = "N/A" STOP_TIME = "N/A" SPACECRAFT_CLOCK_START_COUNT = "N/A" SPACECRAFT_CLOCK_STOP_COUNT = "N/A" TARGET_NAME = MARS INSTRUMENT_NAME = "MARS ORBITER CAMERA" NAIF_INSTRUMENT_ID = -94030 SOURCE_PRODUCT_ID = "N/A" NOTE = "See comments in the file for details" OBJECT = SPICE_KERNEL INTERCHANGE_FORMAT = ASCII KERNEL_TYPE = INSTRUMENT DESCRIPTION = "MGS Mars Orbiter Camera instrument parameters SPICE I-Kernel File. This file also contains MOC Frame definitions. " END_OBJECT = SPICE_KERNEL \endlabel -------------------------------------------------------------------------------- MOC Instrument Kernel =========================================================================== This Mars Orbiter Camera (MOC) instrument kernel (I-kernel) contains the instrument mounting offset, and both the narrow and wide angle fields of view and focal lengths. Version and Date -------------------------------------------------------- Version 1.3 -- September 18, 1998 A few typos were corrected. Version 1.2 -- August 11, 1997 Frame definition was corrected to represent the correct transformation sense. Version 1.1 -- June 19, 1997 The MOC frame definition section was added to support utilization of the SPICE system FRAMES capabilities. Version 1.0 -- November 26, 1996 Initial Release. References -------------------------------------------------------- 1. ``MGS Alignment Transformation'', by Richard A. Hund, November 26, 1996. 2. ``MGS Payload Data Sheet'' by C.Kloss, October 31, 1995, 3. ``C-kernel Required Reading'' 4. ``Kernel Pool Required Reading'' 5. ``Frames Required Reading'' 6. ``Mars Global Surveyor Project Mission Plan'', Final Version, Rev. A (MGS 542-405), July 1996 Implementation Notes -------------------------------------------------------- This file is used by the SPICE system as follows: programs that make use of this I-kernel must `load' the kernel, normally during program initialization. Loading the kernel associates data items with their names in a data structure called the `kernel pool'. The SPICELIB routine LDPOOL loads a kernel file into the pool as shown below. CALL LDPOOL ( I_kernel_name ) In order for a program or subroutine to extract data from the pool, the SPICELIB routines GDPOOL and GIPOOL are used. See [4] for more details. This file was created and may be updated with a text editor or word processor. Naming Conventions -------------------------------------------------------- All names referencing values in this I-kernel start with the characters `INS' followed by the NAIF Mars Global Surveyor spacecraft ID number (-94) followed by the NAIF three digit MOC instrument reference number (030). The remainder of the name is an underscore character followed by the unique name of the data item. For example, the focal length of the MOC narrow angle telescope is specified by INS-94030_NA_FOCAL_LENGTH The upper bound on the length of the name of any data item is 32 characters. If the same item is included in more then one file, or if the same item appears more than once within a single file, the latest value supersedes any earlier values. MOC mounting offset -------------------------------------------------------- This section describes the offset of the MOC instrument fixed frame (the frame fixed to the alignment cube on the MOC) relative to the Mars Global Surveyor spacecraft frame. From the offset, given as three rotation angles -- ROLL, PITCH and YAW, a rotation matrix can be constructed that will transform the components of a vector expressed in the spacecraft frame to components expressed in the MOC instrument fixed frame. For example, if x y and z are the components of a vector expressed in the spacecraft frame, X Y and Z will be the components of the same vector expressed in the MOC instrument fixed frame: [ X ] [ ] [ x ] | Y | = | ROT | | y | [ Z ] [ ] [ z ] where ROT is the rotation matrix constructed from the rotation angles as follows: [ ] [ ] [ ] [ ] [ ROT ] = [ YAW ] [ PITCH ] [ ROLL ] [ ] [ ] [ ] [ ] Z Y X where each of three matrixes on the right side represent a coordinate frame rotation by the given angle around the indicated axis. See the SPICELIB routine EUL2M for more information about constructing a rotation matrix from a set of rotation angles. The following measured values of ROLL, PITCH and YAW are provided in [1]: ROLL = 359.933 (degrees) PITCH = 0.012 (degrees) YAW = 0.180 (degrees) The keyword INS-94030_EULER_ANGLES contains these values, in radians, in the following order: INS-94030_EULER_ANGLES = ( ``ROLL'' ``PITCH'' ``YAW'' ) The keyword INS-94030_EULER_AXES contains integer codes of the corresponding axes of rotations (1 -- X, 2 -- Y, 3 -- Z). \begindata INS-94030_EULER_ANGLES = ( 6.282015936581 0.000209439510 0.003141592654 ) INS-94030_EULER_AXES = ( 1 2 3 ) \begintext Narrow Angle Telescope -------------------------------------------------------- Focal length The narrow angle focal length, from [5], is given below in meters. \begindata INS-94030_NA_FOCAL_LENGTH = ( 3.500 ) \begintext Field of view The narrow angle field of view (FOV), from [2], is a cone of 0.44 degrees. Units are in radians \begindata INS-94030_NA_FOV = ( 0.007679448709 ) \begintext Wide Angle Telescope -------------------------------------------------------- Focal length The Wide angle focal length, from [5], is given below in millimeters. \begindata INS-94030_WA_FOCAL_LENGTH = ( 9.7 ) \begintext Field of view The wide angle field of view, from [2], is 140.2 degrees in the cross-track direction and 3 degrees in the down-track direction. The cross-track direction of the is along the y axis of the instrument, the down-track direction is along the x axis of the instrument, the boresight direction is along Z axis of the instrument. Units are in radians. \begindata INS-94030_WA_CROSS_TRACK_FOV = ( 2.446951611296 ) INS-94030_WA_DOWN_TRACK_FOV = ( 0.052359877560 ) \begintext Platform ID -------------------------------------------------------- This number is the NAIF instrument ID of the platform on which the instrument is mounted. \begindata INS-94030_PLATFORM_ID = ( -94000 ) \begintext Instrument Frame Definition -------------------------------------------------------- The instrument frame definition for MOC. This definiton will be utilized by the SPICE FRAMES subsystem to provide automatic state transformations to/from MOC instrument frame. Note that angles in the frame definitions are specified as "from instrument to base frame" transformation. \begindata FRAME_MGS_MOC = -94030 FRAME_-94030_NAME = 'MGS_MOC' FRAME_-94030_CLASS = 4 FRAME_-94030_CLASS_ID = -94030 FRAME_-94030_CENTER = -94 TKFRAME_-94030_SPEC = 'ANGLES' TKFRAME_-94030_RELATIVE = 'MGS_SPACECRAFT' TKFRAME_-94030_ANGLES = ( -6.282015936581, -0.000209439510, -0.003141592654 ) TKFRAME_-94030_AXES = ( 1, 2, 3 ) TKFRAME_-94030_UNITS = 'RADIANS'