KPL/IK HERA MILANI Navigation Camera Instrument kernel ============================================================================== This instrument kernel (I-kernel) contains the MILANI Navigation Camera (NAVCAM) optics, detector, and field-of-view parameters. Version and Date ------------------------------------------------------------------------------ Version 0.1 -- Sep 21, 2023 -- Ricardo Valles, ESAC/ESA Updated Hera ID according to one provided by DSN and confirmed by FDy: from -999 to -91. Version 0.0 -- May 4, 2023 -- Alfredo Escalante Lopez, ESAC/ESA Preliminary version. References ------------------------------------------------------------------------------ 1. ``Kernel Pool Required Reading'' 2. ``C-kernel Required Reading'' 3. Hera Frames Definition Kernel (FK), latest version. 4. Milani Spacecraft Frames Kernel (FK), latest version. 5. ``Milani Cubesat Instruments'', https://www.heramission.space/hera-mission-milani-cubesat Contact Information ----------------------------------------------------------------------------- If you have any questions regarding this file contact the ESA SPICE Service at ESAC: Alfredo Escalante Lopez (+34) 91-8131-429 spice@sciops.esa.int or NAIF at JPL: Boris Semenov +1 (818) 354-8136 Boris.Semenov@jpl.nasa.gov Implementation Notes ------------------------------------------------------------------------------ Applications that need SPICE I-kernel data must ``load'' the I-kernel file, normally during program initialization. Loading the kernel using the SPICELIB routine FURNSH causes the data items and their associated values present in the kernel to become associated with a data structure called the ``kernel pool''. The application program may then obtain the value(s) for any IK data item using the SPICELIB routines GDPOOL, GIPOOL, GCPOOL. Routine GETFOV may be used if the file contains instrument field-of-view (FOV) specification. See [1] for details. This file was created with, and can be updated with a text editor or word processor. Conventions for Specifying Data ------------------------------------------------------------------------------ Data items are specified using ``keyword=value'' assignments [1]. All keywords referencing values in this I-kernel start with the characters `INS' followed by the NAIF MILANI instrument ID code, constructed using the spacecraft ID number (-9102) followed by the NAIF three digit ID number. The ID numbers are defined in [4] as follows: Instrument name ID -------------------- --------- MILANI_NAVCAM -9102310 The remainder of the keyword is an underscore character followed by the unique name of the data item. For example, the boresight of NAVCAM is specified by INS-9102310_BORESIGHT The upper bound on the length of all keywords is 32 characters. If a keyword is included in more than one file, or if the same keyword appears more than once within a single file, the last assignment supersedes any earlier assignments. Overview ------------------------------------------------------------------------------ From [5]: MILANI counts with a visible Navigation Camera (NAVCAM) devoted to optical navigation around the asteroid. Mounting Alignment ------------------------------------------------------------------------------ Refer to the latest version of the Milani Spacecraft Frames Kernel (FK) [4] for the NAVCAM reference frame definitions and mounting alignment information. Apparent FOV Layout ------------------------------------------------------------------------------ This section provides a diagram illustrating the NAVCAM apparent FOV layout in the corresponding reference frame. For NAVCAM the pixel (0,0) is in the lower left corner of the image, and pixel (2048,1536) is in the top right corner. +X, +Y, +Z axes are defined in the Milani Spacecraft Frames Kernel (FK) [4]. | 21 deg | Boresight (+Z axis) |<----------------->| is into the page | | 2048 pixels/line --- +-------------------+ ^ | | | | | | | +Znav | | 16 deg 1536 | x-------------> +Xnav | lines | | | | | | | V | | | --- (0,0)-------|---------+ Pixel | | v +Ynav Optical Parameters ------------------------------------------------------------------------------ The following NAVCAM nominal first order optical parameters are, from [5]: ------------------------------------ parameter value ------------------------------------ Focal Length, mm 12.96 f/ratio 2.8 IFOV, mrad/pixel 0.17896 x 0.18181 Field of view, deg 21 x 16 Spectral range, mm 400 - 700 Bandwith (FWHM), nm 250 , RGB Bayer filter array Pixel size, um 2.2 x 2.2 ------------------------------------ NAVCAM: \begindata INS-9102310_IFOV = ( 0.00017896, 0.00018181 ) INS-9102310_FOV_ANGULAR_SIZE = ( 0.366519, 0.279253 ) \begintext CCD Parameters ------------------------------------------------------------------------------ The following NAVCAM nominal geometry parameters are, from [5]. ------------------------------------ parameter value ------------------------------------ Pixel size, um 2.2 x 2.2 Detector Array Size 2048 x 1536 Detector Array Center 1024.5 x 768.5 ------------------------------------ The values are given in microns for PIXEL_SIZE keywords and in counts for PIXEL_SAMPLES, PIXEL_LINES, and CENTER keywords. NAVCAM: \begindata INS-9102310_PIXEL_SIZE = ( 2.2, 2.2 ) INS-9102310_PIXEL_SAMPLES = ( 2048 ) INS-9102310_PIXEL_LINES = ( 1536 ) INS-9102310_CCD_CENTER = ( 1024.6, 768.5 ) \begintext Filter Parameters ------------------------------------------------------------------------------ TBD. FOV Definitions ------------------------------------------------------------------------------ This section contains definitions for the NAVCAM FOVs. These definitions are provided in a format required by the SPICE (CSPICE) function GETFOV (getfov_c). The set of assignments in the data section below defines the NAVCAM FOVs with respect to the corresponding frames to be a rectangle with the corners defined by the first and last pixels of the first and last lines of the CCD and the boresight along the +Z axis. This FOV definition uses the FOV_ANGULAR_SIZE values from the ``Optical Parameters'' section above converted to degrees. NAVCAM: \begindata INS-9102310_FOV_FRAME = 'MILANI_NAVCAM' INS-9102310_FOV_SHAPE = 'RECTANGLE' INS-9102310_BORESIGHT = ( 0.0, 0.0, 1.0 ) INS-9102310_FOV_CLASS_SPEC = 'ANGLES' INS-9102310_FOV_REF_VECTOR = ( 1.0, 0.0, 0.0 ) INS-9102310_FOV_REF_ANGLE = ( 10.5 ) INS-9102310_FOV_CROSS_ANGLE = ( 8.0 ) INS-9102310_FOV_ANGLE_UNITS = 'DEGREES' \begintext Optical Distortion ------------------------------------------------------------------------------ TBD. Platform ID ------------------------------------------------------------------------------- This number is the NAIF instrument ID of the platform on which the sensors are mounted. For the Milani Navigation Camera (NAVCAM) platform is spacecraft. Please refer to the latest version of the Milani NAIF ID Codes Definitions [4] for mapping of ID codes to sensor and structure names. \begindata INS-9102310_PLATFORM_ID = ( -9102 ) \begintext End of IK file.