Use Case:  Preset Probe

Description:  Preset the FSS Translation Stage/FAS Reference Point to the given sky position in (alpha, delta) coordinates. The Translation Stage goes to the requested position and tracks the given sky coordinates.

Role(s)/Actor(s): 
Primary: User
Secondary: FSS Translation Stage, FAS

Priority: Major

Performance: 

Frequency: 

Package Assignment:  Field Stabilization Subsystem.

Preconditions: 

• FSS sub-system is ONLINE
• FAS sub-system is ONLINE
• M6 is ONLINE
• probe is tracking

Basic Course: 

• Send command PRABS to preset probe to (alpha,delta) position
  Exception Course: Command failed
• ATCS sets new (alpha, delta) reference position for the FSS Control Loop.
  Exception Course: Command failed
• ATCS waits for the Translation Stage to be tracking at the given (alpha, delta) coordinates.
• ATCS returns OK reply

Exception Course:  Command failed

• ATCS returns ERROR reply
  Postcondition: No motion

Postconditions: 

• FSS XY translation stage tracking at given sky position

Issues to be Determined or Resolved: 

Last modified: Wed Apr 17 07:37:30 UTC 2002