Non-primary option. This is a special use case for SPC. If the file exists, then the code is processed and executed.
BIAS.TXT allows you to make a small systematic shift to the spacecraft in the inertial frame from the SPK. It is designed for when you have a constant offset that you detect during approach and wish to put that same value in for all of the approach images. This allows corrections from REGISTER option G to be used before spk files are changed by FDS for immediate iteration.
The offset in X
The offset in Y
The offset in Z
Units of X, Y and Z are in km.
The file has a single row, which has three entries. The offset in X, Y and Z.
Here is a sample BIAS.TXT file.
.0001 .002 .03