20 October 2008LBT Q Eng/SW Review0 PCS – Pointing Control Subsystem Michele De La Peña

20 October 2008LBT Q Eng/SW Review1 Highlights PCS Interfaces (GCS, MCSPU) PCS Interfaces (GCS, MCSPU) GCS: Pointing Correction GCS: Pointing Correction Improved algorithm which applies the difference between the PCS “predicted” versus the GCS “measured” guide star location Improved algorithm which applies the difference between the PCS “predicted” versus the GCS “measured” guide star location Better handshaking implemented to indicate when it is OK for GCS to verify the guide star is positioned on the hotspot before closing the guide loop Better handshaking implemented to indicate when it is OK for GCS to verify the guide star is positioned on the hotspot before closing the guide loop MCSPU: PCS Cold Start and New Target Trajectories MCSPU: PCS Cold Start and New Target Trajectories Better handshaking implemented which alleviates having to issue duplicate Presets - “Late” PCS trajectory communication  mount/rotator enters HOLD mode  reduces observing efficiency Better handshaking implemented which alleviates having to issue duplicate Presets - “Late” PCS trajectory communication  mount/rotator enters HOLD mode  reduces observing efficiency The philosophy is the mount should react to the ever-changing pointing demand - PCS is a pure compute engine while MCSPU has the responsibility to recognize discontinuities due to new target requests The philosophy is the mount should react to the ever-changing pointing demand - PCS is a pure compute engine while MCSPU has the responsibility to recognize discontinuities due to new target requests Functionality to Support Instruments Functionality to Support Instruments New functionality allows the observer to reposition where a target is imaged in the instrument focal plane (“hotspot” update) – pointing origin update vs dither. New functionality allows the observer to reposition where a target is imaged in the instrument focal plane (“hotspot” update) – pointing origin update vs dither. Observers can update the effective target wavelength (due to changing filters) and not have to issue a new Preset  improved efficiency Observers can update the effective target wavelength (due to changing filters) and not have to issue a new Preset  improved efficiency

20 October 2008LBT Q Eng/SW Review2 Open Issues Technical Technical Investigation of guiding issues (jumps/jiggles/jitters) Investigation of guiding issues (jumps/jiggles/jitters) Resolve the LBC “guide correction growth” problem  random occurrence Resolve the LBC “guide correction growth” problem  random occurrence Tuning of gains and filters used to modulate the Az/El guiding corrections to avoid over-correction and system oscillation Tuning of gains and filters used to modulate the Az/El guiding corrections to avoid over-correction and system oscillation Discussion on-going and an actual plan being formulated for near-term data collection Discussion on-going and an actual plan being formulated for near-term data collection Thorough examination of kernel guide correction filter and application Thorough examination of kernel guide correction filter and application Resolve high elevation guide oscillations (somewhat addressed in new kernel) Resolve high elevation guide oscillations (somewhat addressed in new kernel) Achieve definitive understanding of the various kernel angles, transformations, and trajectory offsets to apply a comprehensive solution for each instrument Achieve definitive understanding of the various kernel angles, transformations, and trajectory offsets to apply a comprehensive solution for each instrument Evaluate and utilize the updated (and slightly incompatible) pointing kernel Evaluate and utilize the updated (and slightly incompatible) pointing kernel Schedule Schedule Concern not enough on-sky testing time for technical observing Concern not enough on-sky testing time for technical observing Primarily weather, but also sky time scarce resource for testing (unit and integration) Primarily weather, but also sky time scarce resource for testing (unit and integration) Reconcile expectations when programmer participating in on-sky instrument support and required to implement new and robust functionality Reconcile expectations when programmer participating in on-sky instrument support and required to implement new and robust functionality Financial Financial Continued support for RAL consulting Continued support for RAL consulting Resource Resource None None

20 October 2008LBT Q Eng/SW Review3 Planning (Q4/2008) Resolution of the “Open Issues” (Oct…) Resolution of the “Open Issues” (Oct…) Initiation of a new PCS GUI (Dec) Initiation of a new PCS GUI (Dec) Incorporates the functionality from current PCS and Preset GUIs Incorporates the functionality from current PCS and Preset GUIs Provides additional control and monitoring Provides additional control and monitoring Sets the migration path for binocular support Sets the migration path for binocular support Implement telemetry module Implement telemetry module True Binocular Support (Dec…) True Binocular Support (Dec…) Implementation of basic structural modifications to PCS to accommodate the binocular arbitrator (Dec…) Implementation of basic structural modifications to PCS to accommodate the binocular arbitrator (Dec…) Define/design interface between the PCS and PSF for the tip/tilt computation (Q1/2009) Define/design interface between the PCS and PSF for the tip/tilt computation (Q1/2009) Elaborate/design the model for co-aligned and misaligned observations (Q1/2009) Elaborate/design the model for co-aligned and misaligned observations (Q1/2009) Implementation commencement – LBC emphasis (Q1/2009) Implementation commencement – LBC emphasis (Q1/2009)