1. LBT Q1 2008 Eng/SW Review HBSC Hydrostatic Bearing System Sargent/Kern

2. 04-Apr-2008LBT Q1 2008 Eng/SW Review Highlights (Q1/2008) Proximity sensors were installed on the left rear elevation pad and initial installation was made of a set of oil flow reducing capillaries. Small moves were made taking the telescope from horizon to zenith with the capillaries installed, when we attempted to move the telescope back to horizon from zenith we ran aground at 81 degrees. Ran out or Engineering time, the capillaries have been removed and installation will continue when time becomes available. Proximity sensors were installed on the left rear elevation pad and initial installation was made of a set of oil flow reducing capillaries. Small moves were made taking the telescope from horizon to zenith with the capillaries installed, when we attempted to move the telescope back to horizon from zenith we ran aground at 81 degrees. Ran out or Engineering time, the capillaries have been removed and installation will continue when time becomes available. Extraction of flowchart for existing PLC code is nearly complete (130 pages). Extraction of flowchart for existing PLC code is nearly complete (130 pages). Siemens/LINUX interface agreed upon and ordered Siemens/LINUX interface agreed upon and ordered

3. 04-Apr-2008LBT Q1 2008 Eng/SW Review Open Issues Technical Technical PLC Control law unknown, undocumented. PLC Control law unknown, undocumented. Firewall not penetrable for WinCC Firewall not penetrable for WinCC Capillaries not installed in any El and Az pads Capillaries not installed in any El and Az pads Schedule Schedule None None Financial Financial None None Resource Resource Mountain support pacing operation Mountain support pacing operation Network and Firewall communications issues unresolved Network and Firewall communications issues unresolved

4. 04-Apr-2008LBT Q1 2008 Eng/SW Review Progress (Q1/2008) Capillary adaptors installed on EL in L-R corner. Capillary adaptors installed on EL in L-R corner. Limited measurements made with proximity sensor Limited measurements made with proximity sensor Flow Chart nearly complete Flow Chart nearly complete Siemens/LINUX interface agreed upon and ordered Siemens/LINUX interface agreed upon and ordered

5. 04-Apr-2008LBT Q1 2008 Eng/SW Review Planning (Q2/2008) Move the El and Az capillaries at the pads and resize Move the El and Az capillaries at the pads and resize Systematic measurement of lift, tuning system to maximize stiffness Systematic measurement of lift, tuning system to maximize stiffness Replace hoses with hard pipe on level 5 Replace hoses with hard pipe on level 5 Receive existing S7 code properly flowcharted (VoltsDC) Receive existing S7 code properly flowcharted (VoltsDC) Install Siemens/LINUX interface Install Siemens/LINUX interface Describe new control laws correcting: Describe new control laws correcting: pressure OK pressure OK system shutdown when pocket pressures fail system shutdown when pocket pressures fail control around pressure, not lookup table (LBT) control around pressure, not lookup table (LBT) Rewrite PLC code using new control laws (VoltsDC) Rewrite PLC code using new control laws (VoltsDC) Reduce system pressure from 120 to 95 bar. Reduce system pressure from 120 to 95 bar. MCSPU software revisions: MCSPU software revisions: Modify HBS Control/monitor State machine to use newly available tags Modify HBS Control/monitor State machine to use newly available tags Amend HBS Command set as needed Amend HBS Command set as needed Display detailed HBS status in Eng. Interface display page Display detailed HBS status in Eng. Interface display page Use new CTI PLCIO to communicate with both AB TPLC and Siemens HPLC Use new CTI PLCIO to communicate with both AB TPLC and Siemens HPLC MCS needs to copy HBS status info into shared memory for rest of TCS. MCS needs to copy HBS status info into shared memory for rest of TCS. Add HBS information and commands to MCS GUI Add HBS information and commands to MCS GUI